Our project as is entitled is aimed at avoiding the serious accidents caused by leakage of LPG gas at domestic or industrial. The main aim of achieving is resolving the gas leakage like LPG gas and here it’s done by LPG gas sensor named MQ-5.Apart from gas sensor, GSM module SIM900 a is used to communicate between the sensor and user with the help of Micro Controller as an interface by sending the respective At commands. An exhaust fan is also been used to eliminate the LPG gas when detected.
Here the gas produced is from cigarette lighter. So when this gas is detected by MQ-5 gas sensor, the output of the sensor becomes logic LOW when the gas content reaches the threshold value calibrated within the sensor. Now the Micro Controller UNO which is connected to the gas sensor output the respective At commands are sent to the GSM module in accordance to the Micro Controller coding. The GSM module then sends a message warning to the members of the household.
With this sort of equipment we are able to detect the presence of LPG gas anywhere and our project is aimed at detecting the LPG gas at homes when leaked in the absence of people and alert them and thus avoid major accidents and then prevent the loss of life of people.
List of Figures
Chapter 1: Introduction
|1.2 Related work||2|
| 1.3 Proposed work
|Chapter 2: Literature Survey||4|
|2.1 Existing Methodology||5|
| 2.2 Proposed Methodology
|Chapter 3: Hardware Implementation||8|
|3.1 Power Supply||8|
|3.1.3 Control transformation strategy||8|
|3.1.4 DC Power supply||9|
|3.1.5 Air conditioning to-DC supply||10|
|3.1.6 Straight controller||11|
|3.1.7 Air conditioning power supplies||11|
| 3.1.8 Exchanged mode control supply
3.19 Programmable power supply
3.20 Uninterruptible power supply
3.21 High voltage control supply
|3.2 Atmega 16||13|
|3.2.3 Pin Diagram||15|
| 3.2.4 Pin Description
|3.3.2 GSM Advantages||20|
|3.3.3 The GSM Network||20|
|3.3.4 The Switching System||21|
|3.3.5 The Base Station System||22|
|3.3.6 GSM Network Areas||23|
|3.3.7 GSM Specifications||24|
|3.3.8 GSM Subscriber Services||24|
|3.3.9 Supplementary Services||25|
|3.3.10 Main AT Commands||26|
|3.3.11 Minimum Functionality mode||27|
|3.3.12 SIM 300||29|
|3.4 Voltage Regulator||30|
|3.4.3 Pin Diagram||30|
|3.4.4 Pin Description||31|
|3.4.5 Inner circuit of 7805||31|
|3.5.2 Types of sensors||33|
|3.5.2 a gas sensor||33|
|3.5.2 b Specifications||36|
|3.5.2 c Features||36|
|3.5.2 d Types of LPG Detection Sensors||36|
|18.104.22.168 d MQ2,MQ3,MQ4,MQ5,MQ6||35-43|
|3.6.2 Basic Principle||43|
|3.6.3 LED Display Types||44|
| 3.6.4 Applications
3.7 max 232
|Chapter 4: Software Implementation|
| 4.1 Software implemented
4.1.1 Device Architecture
4.1.2 Program Memory
| 4.2 Internal Registers
4.2.1 GPIO Ports
4.3 Instruction Set
4.5 Debugging Interfaces
4.6.1. Flow chart of Micro Controller
4.6.2. Flowchart of GSM Module
4.6.3. Flowchart of Gas sensor
Chapter 5: Results and Discussions
Chapter 6: Advantages and Disadvantages
6.3 Future Scope
Chapter 7: Conclusion and References
Chapter 8: Annexure
LIST OF FIGURES
|3.2 Pin Diagram of Atmega 16||15|
|3.3.1 GSM block diagram||20|
|3.3.2 GSM network areas||23|
|3.4 Pin diagram of 7805||30|
|3.4.1 Inner circuit of 7805||31|
|3.6.1 Basic principle of LED||44|
|3.6.2 LED types||45|
|3.7.1 Pin diagram of MAX RS232||48|
4.1 Flow Chart 58
4.2. Flowchart of microcontroller 59
4.3. Flowchart of GSM Module 60
4.4. Flow chart of Gas Sensor 60
5.1 Output 64
LIST OF TABLES
|3.2.4 Pin Description of Atmega 16||16|
|3.4.4 Pin description of 7805||33|
In this paper at the present age, safety has become an necessary issue for most of the people in all areas. Safety precautions and continuous monitoring of every part of the world is required. It is not possible for humans to continuously monitor all the equipment and manually detect any errors if present. All this data can be continuously seen in a mobile using GSM module. When any of the mishaps is detected then immediately a concerned action takes place without human intervention. And when there is any gas leakage has been detected message will be sent to the required phone number as per the code.
LPG consists of mixture of propane and butane which is highly flammable chemical. It is odour less gas due to which Ethanethiol is added as powerful odorant, so that leakage can be easily detected. We can detect the presence of dangerous LPG leakage in the cars, industrial sectors and residential premises using an Ideal Gas Sensor. We can easily integrate the LPG gas leakage detector unit into a unit that can sound an alarm or give a visual suggestion of the LPG concentration. The sensor used in this Project will have both admirable sensitivity and rapid response time. This sensor can also be used to sense other gases like iso-butane, propane, LNG and even cigarette smoke. The output of the sensor goes LOW as soon as the LPG sensor senses any gas leakage. This is detected by the microcontroller and the LED & buzzer are turned ON. After a delay of few milliseconds, the exhaust fan is also turned ON for throwing the gas out and a “GAS LEAKAGE” message is sent to a pre-defined mobile number using GSM Module. There are mainly three units, in this circuit: sensor unit, microcontroller unit and GSM modem. For detecting dangerous & flammable gas leaks in any closed environment such as a car, house, service station or storage tank, a gas sensor is used which detects natural gas, LPG and coal gas. This sensor can also be used to sense other gases like iso-butane, propane and even cigarette smoke.
1.2. RELATED WORK:
The purpose of this project is to continuously monitor the home without human intervention and immediately rectify it to minimize the loss of human and assets. To rectify the loss which we discuss above we are implementing this project. In this project Micro Controller is in turn connected to the GSM module. When the gas is detected message will be sent to the number written in the code. And for the purpose of storing the number we will use the AT commands. The designed system prevents gas leakage inside homes as well as outside homes. The system detects the LPG gas concentration in the air if it exceeds a safety level and then responds by using GSM to send an SMS to the consumer. The LED and Buzzer are activated to alert the consumer in case of gas leakage.
1.3 PROPOSED WORK:
Here the gas produced is from cigarette lighter. So when this gas is detected by MQ-5 gas sensor, the output of the sensor becomes logic LOW when the gas content reaches the threshold value calibrated within the sensor. Now the Micro Controller UNO which is connected to the gas sensor output the respective At commands are sent to the GSM module in accordance to the Micro Controller coding. The GSM module then sends a message warning to the members of the household.
Gas leakage is a major problem with industrial sector, residential premises and gas powered vehicles like CNG (Compressed Natural Gas) buses, cars etc. One of the preventive methods to stop accidents associated with the gas leakage is to install a gas leakage detection device at vulnerable places. The aim of this project is to develop such a device that can automatically detect and stop gas leakages in vulnerable areas. The system detects the leakage of the LPG (Liquefied Petroleum Gas) using a gas sensor and uses the GSM to alert the person about the gas leakage via SMS. When the LPG concentration in the air exceeds a certain level, the gas sensor senses the gas leakage and the output of the sensor goes LOW. This is detected by the microcontroller and the LED and buzzer are turned ON simultaneously. The system then alerts the customer by sending an SMS to the specified mobile-phone.
The solution provided can be further enhanced by displaying in the LCD unit how much amount of gas is leaked. We can also incorporate the location detection feature for the gas leakage area for which SIM900 is purposely used as it comes with added feature of web interfacing by using some extra codes in the microcontroller programming.MQ-5 Semiconductor Sensor for Combustible Gas Sensitive material of MQ-5 gas sensor is SnO2, which with lower conductivity in clean air. When the target combustible gas exist, the sensors conductivity is higher along with the gas concentration rising. We use simple electro-circuit, convert change of conductivity to correspond output signal of gas concentration. MQ-5 gas sensor has high sensitivity to Methane, Propane and Butane and could be used to detect both Methane and Propane. The sensor could be used to detect different combustible gas especially Methane, it is with low cost and suitable for different application.
- To detect the leakage of LPG gas in a closed environment, if any.
- To inform the user about the leakage of gas via SMS.
- To activate the alarm unit to inform neighbor about the gas leakage.
In this chapter the introduction related to the project is covered i.e…How the input is given and what is the main theme of this project and how the output is observed and calculated. What are the measures to be taken in this project in order to get the exact results.
LPG consists of mixture of gases like propane and butane. These gases can catch fire easily. LPG is used as propellant, fuel and as a refrigerant. When a leak occurs, the leaked gases may lead to explosion. The number of deaths occurring due to explosion of gas cylinders has increased. So the leakage should be controlled to protect people from danger. Bhopal gas tragedy is an example for accidents due to gas leakage. Gas leakage detection is not only important but controlling the leakage is also important. Liquid petroleum gas is generally used in houses and industries. In homes, LPG is used mainly for cooking purpose. This energy source is primarily composed of propane and butane which are highly flammable chemical compounds.
LPG leaks can happen, though rarely, inside a home, commercial premises or in gas powered vehicles. Leakage of this gas can be dangerous as it enhances the risk of explosion. An odorant such as ethanethiol is added to LPG, so that leaks can be detected easily by most people. However, some people who have a reduced sense of smell may not be able to rely upon this inherent safety mechanism. In such cases, a gas leakage detector becomes vital and helps to protect people from the dangers of gas leakage. A number of research papers have been published on gas leakage detection techniques. In this project, advanced gas leakage detection technology is used.
Meenakshi Vidya proposed the leakage detection and real time gas monitoring system. In this system, the gas leakage is detected and controlled by means of exhaust fan. The level of LPG in cylinder is also continuously monitored.
K.Padmapriya proposed the design of wireless LPG monitoring system. In this project, the user is alerted about the gas leakage through SMS and the power supply is turned off.
Selvapriya proposed the system in which the leakage is detected by the gas sensor and produce the results in the audio and visual forms. It provides a design approach on software as well as hardware.
L.K.Hema proposed the smart sensor technology. In this flexible reliable smart gas detection system is developed. In this, the leakage is detected and controlled by using exhaust fan.
B. D. Jolhe proposed the system in which two sensors are used for detecting the gas leakage and for monitoring the level of gas in the cylinder respectively.
Ashish Shrivastava proposed the system in which two types of gases namely LPG and CNG are detected for home safety as well for vehicles.
R.Padmapriya proposed the system which ARM7 processor and simulates using ATMEL software to alert the user by sending SMS. V.Ramya proposed the system that uses two different sensors for detecting the leakage and requires resetting manually after every situation.
A.Mahalingam proposed the system to meet UK occupational health and safety standards and also it alerts the user by SMS.M.B.Frish proposed the system that uses trace sensing technology and also detects the leakage.
2.1. EXISTING METHODOLOGY
In the existing method, different gas sensing technology is used. The LPG gas leakage is detected by the semiconductor sensor. Nowadays LPG accidents occur very common. The main reason of these accidents is due to the leakage of LPG. This leakage of LPG starts when we forget to close the main regulator valve. This is the basis of these kinds of accidents. Already there are some sorts of remedial measures such as when the leakage is detected; message is sent to the fire station and the owner. The other remedial measure is that when the leakage is detected, exhaust fan is switched on. The first mentioned method has the disadvantage that there is no control action taken, it needs a manual controlling which puts human into direct risk. The second method has the disadvantage that if the wiring of the exhaust fan is not proper then it will cause immediate explosion due to the flow of AC. In all these mentioned method above, there is only detection no control action is taken.
2.2. PROPOSED METHODOLOGY
The proposed system takes an automatic control action after the detection of 0.001% of LPG leakage. This automatic control action provides a mechanical handle for closing the valve. We are increasing the security for human by means of a relay which will shut down the electric power to the house. Also by using GSM, we are sending an alert message to the users and a buzzer is provided for alerting the neighbors about the leakage.
Various research groups are working all over the world for the development of Microcontroller based LPG Gas Leakage Detectors using GSM Module. LPG, first produced in 1910 by Dr. Walter Snelling is a mixture of Commercial Propane and Commercial Butane having saturated as well as unsaturated hydrocarbons. Before the development of electronic household gas detectors in the 1980s and 90s, gas presence was detected with a chemically infused paper that changed its colour when exposed to the gas. Since then, many technologies and devices have been developed to detect, monitor, and alert the leakage of a wide array of gases.
The main applications of a LPG Gas Leakage Detector would be :
• To protect ourselves from any gas leakage in cars, industries, homes, hospitals etc.
• To safeguard ourselves from gas leakage in heating gas fired appliances like boilers, domestic water heaters.
• To be used in large industries which use gas as their production.
• To provide safety from gas leakage in cooking gas fired appliances like ovens, stoves etc.
This project has many advantages which are as follows:
• The Project is easy to use and it gives remote indication to the user.
• The Sensor utilized as a part of this Project has phenomenal affectability consolidated with a speedy quick reaction time.
The framework is exceedingly solid, carefully designed and secure. In the long run the support cost is less when contrasted with the present frameworks. It is conceivable to get momentary outcomes and with high exactness.
This Project has a great deal of Future Scope as in utilizing this venture we can give a voice input framework later on. With late advancement in innovation, Temperature show amid periods wherein no message supports are vacant is one such hypothetical change that is well conceivable. Another extremely fascinating and huge change is suit various recipient MODEMS at various positions in the topographical zone conveying copy SIM cards. Multilingual show can be another additional variety in the venture. Sound yield can be acquainted with make it easy to use.
SnO2 metal oxide is utilized as a part of TGS gas sensor. At the point when SnO2 is warmed at a specific temperature in air, the oxygen gets retained on the precious stone surface with a negative charge. From the gem surface benefactor electrons are exchanged to the assimilated oxygen which brings about leaving positive charges in the space charge layer. Along these lines the surface potential fills in as a potential boundary against the electron stream. In the sensor the electric current streams in the sensor through mix some portion of SnO2 miniaturized scale precious stones. Potential obstruction shapes at the grain limits which keep the transporter to move openly. The electrical resistance of the sensor is perceived by this potential hindrance within the sight of deoxidizing gas which diminishes the obstruction tallness in the grain limit. The sensor resistance diminishes because of this decreased boundary tallness.
In this chapter the Literature survey related to the project is covered and the various proposed works related to the project are mentioned and the existing works are also mentioned which shows the existence of the project in the practical world.
3.1 POWER SUPPLY:
A power supply is an electronic gadget that provisions electric vitality to an electrical load. The essential capacity of a power supply is to change over one type of electrical vitality to another and, thus, control supplies are now and again alluded to as electric power converters. Some power supplies are discrete, remain solitary gadgets, though others are incorporated with bigger gadgets alongside their heaps. Cases of the last incorporate power supplies found in desktop PCs and purchaser gadgets.
Each power supply must acquire the vitality it supplies to its heap, and additionally any vitality it devours while playing out that assignment, from a vitality source. Contingent upon its plan, a power supply may get vitality from different sorts of vitality sources, including electrical vitality transmission frameworks, vitality stockpiling gadgets, for example, a batteries and energy units, electromechanical frameworks, for example, generators and alternators, sun powered power converters, or another power supply.
All power supplies have a power info, which gets vitality from the vitality source, and a power yield that conveys vitality to the heap. In most power supplies the power information and yield comprise of electrical connectors or hardwired circuit associations, however some power supplies utilize remote vitality move in lieu of galvanic associations for the power information or yield. Some power supplies have different sorts of sources of info and yields also, for capacities, for example, outside checking and control.
Control supplies are classified in different courses, including by useful components. For instance, a managed control supply is one that keeps up steady yield voltage or current notwithstanding varieties in load current or info voltage. On the other hand, the yield of an unregulated power supply can change essentially when its info voltage or load current changes. Movable power supplies permit the yield voltage or current to be modified by mechanical controls (e.g., handles on the power supply front board), or by methods for a control input, or both. A customizable managed control supply is one that is both movable and controlled. A secluded power supply has a power yield that is electrically autonomous of its energy input; this is rather than other power supplies that share a typical association between power info and yield
Control supplies are bundled in various ways and characterized likewise. A seat control supply is a remain solitary desktop unit utilized as a part of uses, for example, circuit test and advancement. Open casing power supplies have just a halfway mechanical walled in area, now and then comprising of just a mounting base; these are commonly incorporated with apparatus or other hardware. Rack mount control supplies are intended to be secured into standard electronic gear racks. An incorporated power supply is one that imparts a typical printed circuit board to its heap.
3.1.3 Control transformation strategy
Control supplies can be comprehensively separated into straight and exchanging sorts. Straight power converters prepare the information control specifically, with all dynamic power transformation segments working in their direct working locales. In exchanging power converters, the information power is changed over to AC or to DC beats before handling, by segments that work prevalently in non-straight modes (e.g., transistors that invest the majority of their energy in cutoff or immersion). Power is “lost” (changed over to warmth) when segments work in their direct areas and, therefore, exchanging converters are generally more effective than straight converters on the grounds that their segments invest less energy in straight working locales.
3.1.4 DC Power Supply
A DC control supply is one that provisions a steady DC voltage to its heap. Contingent upon its outline, a DC control supply might be fueled from a DC source or from an AC source, for example, the power mains.
3.1.5 Air conditioning to-DC supply
Some DC control supplies utilize AC mains power as a vitality source. Such power supplies will at times utilize a transformer to change over the info voltage to a higher or lower AC voltage. A rectifier is utilized to change over the transformer yield voltage to a shifting DC voltage, which thusly is gone through an electronic channel to change over it to an unregulated DC voltage.
The channel evacuates most, however not the majority of the AC voltage varieties; the rest of the AC voltage is known as swell. The electric load’s resilience of swell directs the base measure of sifting that must be given by a power supply. In a few applications, high swell is endured and subsequently no separating is required. For instance, in some battery charging applications it is conceivable to execute a mains-controlled DC control supply with simply a transformer and a solitary rectifier diode, with a resistor in arrangement with the yield to restrain charging current.
3.1.6 Straight controller
The capacity of a straight voltage controller is to change over a fluctuating DC voltage to a steady, frequently particular, bring down DC voltage. Likewise, they regularly give a present restricting capacity to shield the power supply and load from over current (unreasonable, possibly dangerous current). A consistent yield voltage is required in many power supply applications, yet the voltage gave by numerous vitality sources will fluctuate with changes in load impedance. Moreover, when an unregulated DC control supply is the vitality source, its yield voltage will likewise shift with changing info voltage. To go around this, some power supplies utilize a straight voltage controller to keep up the yield voltage at an enduring worth, autonomous of changes in info voltage and load impedance. Straight controllers can likewise diminish the size of swell and commotion on the yield voltage.
3.1.7 Air conditioning power supplies
An AC control supply commonly takes the voltage from a divider outlet (mains supply) and brings it down to the coveted voltage. Some separating may happen also. In present day utilize, AC control supplies can be isolated into single stage and three stage frameworks. “The essential distinction between single stage and three stage AC power is the steadiness of conveyance.” AC control Supplies can likewise be utilized to change the recurrence and also the voltage, they are frequently utilized by makers to check the reasonableness of their items for use in different nations. 230V 50 Hz or 115 60 Hz or even 400 Hz for flying testing.
3.1.8 Exchanged mode control supply
In an exchanged mode control supply (SMPS), the AC mains info is straightforwardly redressed and after that sifted to acquire a DC voltage. The subsequent DC voltage is then turned on and off at a high recurrence by electronic exchanging hardware, in this manner creating an AC current that will go through a high-recurrence transformer or inductor. Exchanging happens at a high recurrence along these lines empowering the utilization of transformers and channel capacitors that are substantially littler, lighter, and more affordable than those found in straight power supplies working at mains recurrence. After the inductor or transformer optional, the high recurrence AC is corrected and separated to deliver the DC yield voltage. On the off chance that the SMPS utilizes an enough protected high-recurrence transformer, the yield will be electrically separated from the mains; this component is regularly fundamental for security. Exchanged mode control supplies are typically managed, and to keep the yield voltage steady, the power supply utilizes a criticism controller that screens current drawn by the heap. The exchanging obligation cycle increments as power yield prerequisites increment. SMPSs frequently incorporate security elements, for example, current restricting or a crowbar circuit to help shield the gadget and the client from damage. If an unusual high-current power draw is recognized, the exchanged mode supply can accept this is an immediate short and will close itself down before harm is finished. PC control supplies frequently give a power decent flag to the motherboard; the nonattendance of this flag counteracts operation when strange supply voltages are available.
Some SMPSs have an outright cutoff on their base current output. They are just ready to yield over a specific power level and can’t work underneath that point. In a no-heap condition the recurrence of the power cutting circuit increments to awesome speed, making the secluded transformer go about as a Tesla loop, bringing about harm because of the subsequent high voltage control spikes. Exchanged mode supplies with insurance circuits may quickly turn on yet then close down when no heap has been identified. A little low-control sham load, for example, a fired power resistor or 10-watt light can be joined to the supply to permit it to keep running with no essential load connected.
The switch-mode control supplies utilized as a part of PCs have generally had low power consider and have additionally been critical wellsprings of line impedance (because of incited electrical cable music and drifters). In basic switch-mode control supplies, the information stage may misshape the line voltage waveform, which can antagonistically influence different loads (and result in poor power quality for other utility clients), and cause superfluous warming in wires and appropriation gear. Besides, clients cause higher electric bills when working lower control figure loads. To go around these issues, some PC switch-mode control supplies perform control consider remedy, and may utilize input channels or extra changing stages to decrease line impedance.
3.19 Programmable power supply
A programmable power supply is one that permits remote control of its operation through a simple info or computerized interface, for example, RS232 or GPIB. Controlled properties may incorporate voltage, current, and on account of AC yield control supplies, recurrence. They are utilized as a part of a wide assortment of utilizations, including mechanized gear testing, gem development observing, semiconductor creation, and x-beam generators.
Programmable power supplies normally utilize a vital microcomputer to control and screen control supply operation. Control supplies outfitted with a PC interface may utilize exclusive correspondence conventions or standard conventions and gadget control dialects, for example, SCPI.
3.20 Uninterruptible power supply
A uninterruptible power supply (UPS) takes its energy from at least two sources all the while. It is generally controlled straightforwardly from the AC mains, while at the same time charging a capacity battery. Ought to there be a dropout or disappointment of the mains, the battery immediately assumes control so that the heap never encounters an intrusion. In a PC establishment, this gives the administrators time to close down the framework in a precise way. Different UPS plans may utilize an inner burning motor or turbine to consistently supply energy to a framework in parallel with power originating from the AC. The motor driven generators would typically be sitting, however could come to full power in a matter of a few moments so as to keep essential gear running without interference. Such a plan may be found in healing facilities or phone focal workplaces.
3.21 High voltage control supply
A high voltage control supply is one that yields hundreds or thousands of volts. An exceptional yield connector is utilized that anticipates arcing, protection breakdown and unplanned human contact. Government Standard connectors are commonly utilized for applications over 20 kV, however different sorts of connectors (e.g., SHV connector) might be utilized at lower voltages. Some high voltage control supplies give a simple info that can be utilized to control the yield voltage. High voltage control supplies are ordinarily used to quicken and control electron and particle pillars in gear, for example, x-beam generators, electron magnifying lens, and centered particle shaft sections, and in an assortment of different applications, including electrophoresis and electrostatics.
High voltage control supplies commonly apply the majority of their info vitality to a power inverter, which thus drives a voltage multiplier or a high turns proportion, high voltage transformer, or both (as a rule a transformer took after by a multiplier) to create high voltage. The high voltage is passed out of the power supply through the extraordinary connector, and is additionally connected to a voltage divider that proselytes it to a low voltage metering signal perfect with low voltage hardware. The metering sign is utilized by a shut circle controller that directs the high voltage by controlling inverter input power, and it might likewise be passed on out of the power supply to permit outer hardware to screen the high voltage yield.
The appropriateness of a specific power supply for an application is dictated by different qualities of the power supply, which are ordinarily recorded in the power supply’s determination. Regularly indicated qualities for a power supply include:
- Input voltage sort (AC or DC) and range
- Efficiency of energy change
- The measure of voltage and current it can supply to its heap
- How stable its yield voltage or current is under changing line and load conditions
- How long it can supply vitality without refueling or reviving (applies to power supplies that utilize versatile vitality sources)
- Operating and capacity temperature ranges
3.2 ATMEGA 16:
A microcontroller regularly fills in as the “cerebrum” of a mechatronic framework. Like a smaller than normal, independent PC, it can be customized to cooperate with both the equipment of the framework and the client. Indeed, even the most fundamental microcontroller can perform basic math operations, control advanced yields, and screen computerized inputs. As the PC business has advanced, so has the innovation related with Micro Controllers. More current microcontrollers are significantly quicker, have more memory, and have a large group of info and yield highlights that midget the capacity of prior models. Most present day controllers have simple to-advanced converters, fast clocks and counters; interfere with abilities, yields that can be heartbeat width regulated, serial correspondence ports, and so forth.
1. Superior, Low-control AVR® 8-bit Microcontroller
2. Propelled RISC Architecture
– 131 Powerful Instructions – Most Single-clock Cycle Execution
– 32 x 8 General Purpose Working Registers
– Fully Static Operation
– Up to 16 MIPS Throughput at 16 MHz
– On-chip 2-cycle Multiplier
3. High Endurance Non-unpredictable Memory fragments
– 16K Bytes of In-System Self-programmable Flash program memory
– 512 Bytes EEPROM
– 1K Byte Internal SRAM
– Write/Erase Cycles: 10,000 Flash/100,000 EEPROM
– Data maintenance: 20 years at 85°C/100 years at 25°C (1)
– Optional Boot Code Section with Independent Lock Bits In-System
4. Programming by On-chip Boot Program
5. Genuine Read-While-Write Operation
3.2.3. PIN DIAGRAM
Fig.3.1.Pin diagram on Atmega 16
3.2.4 PIN DESCRIPTION OF MICROCONTROLLER :
|PIN1||I/O , T0 ( Timer0 External Counter Input) ,XCK : USART External Clock I/O|
|PIN2||I/O, T1 (Timer1 External Counter Input)|
|PIN3||I/O, AIN0: Analog Comparator Positive Input , INT2: External Interrupt 2 Input|
|PIN4||I/O, AIN1: Analog Comparator Negative Input, OC0 : Timer0 Output Compare Match Output|
|PIN9||Reset Pin, Active Low Reset|
|PIN14||(RXD) ,I/O PIN 0,USART Serial Communication Interface|
|PIN15||(TXD) ,I/O Pin 1,USART Serial Communication Interface|
|PIN16||(INT0),I/O Pin 2, External Interrupt INT0|
|PIN17||(INT1),I/O Pin 3, External Interrupt INT1|
|PIN18||(OC1B),I/O Pin 4, PWM Channel Outputs|
|PIN19||(OC1A),I/O Pin 5, PWM Channel Outputs|
|PIN20||(ICP), I/O Pin 6, Timer/Counter1 Input Capture Pin|
|PIN21||(OC2),I/O Pin 7,Timer/Counter2 Output Compare Match Output|
|PIN22||(SCL),I/O Pin 0,TWI Interface|
|PIN23||(SDA),I/O Pin 1,TWI Interface|
|PIN28 :||(TOSC1),I/O Pin 6,Timer Oscillator Pin 1|
|PIN29 :||(TOSC2),I/O Pin 7,Timer Oscillator Pin 2|
|PIN30 :||AVCC (for ADC)|
|PIN31 :||GND (for ADC)|
|PIN33 – PIN40||PAx: I/O,ADCx (Where x is 7 – 0)|
Table.3.1.Pin Description of Atmega 16
Atmel AVR is 8 bit microcontroller. Every one of its ports are 8 bit wide. Each port has 3 registers related with it every one with 8 bits. Each piece in those registers designs pins of specific port. Bit0 of these registers is related with Pin0 of the port; Bit1 of these registers is related with Pin1 of the port and in like manner for different bits.
These three registers are as per the following:
(x can be supplanted by A,B,C,D according to the AVR you are utilizing)
– DDRx enroll
– PORTx enroll
– PINx enroll
DDRx (Data Direction Register) arranges information heading of port pins. Implies its setting decides if port pins will be utilized for info or yield. Composing 0 to a bit in DDRx makes comparing port stick as information, while composing 1 to a bit in DDRx makes relating port stick as yield.
o to make all pins of port An as info pins :
DDRA = 0b00000000;
o to make all pins of port An as yield pins :
DDRA = 0b11111111;
o to make bring down snack of port B as yield and higher snack as info :
DDRB = 0b00001111;
PINx (Port IN) used to peruse information from port pins. So as to peruse the information from port stick, first you need to alter port’s information course to enter. This is finished by setting bits in DDRx to zero. In the event that port is made yield, then perusing PINx enroll will give you information that has been yield on port pins.
Presently there are two info modes. It is possible that you can utilize port sticks as tri expressed sources of info or you can initiate inner draw up. It will be clarified instantly.
PORTx is utilized for two purposes.
1) To yield information: when port is arranged as yield
When you set bits in DDRx to 1, comparing pins moves toward becoming yield pins. Presently you can compose information into individual bits in PORTx enroll. This will instantly change condition of yield pins as indicated by information you have composed. As it were to yield information on to port pins, you need to compose it into PORTx enroll. However remember to set information course as yield.
2) To enact/deactivate pull up resistors: when port is designs as info
When you set bits in DDRx to 0, i.e. make port sticks as information sources, then comparing bits in PORTx enlist are utilized to actuate/deactivate pull-up registers related with that stick. To enact pull-up resister, set piece in PORTx to 1, and to deactivate (i.e. to make port stick tri expressed) set it to 0. In information mode, when draw up is empowered, default condition of stick moves toward becoming ‘1’. So regardless of the possibility that you don’t interface anything to stick and in the event that you attempt to peruse it, it will read as 1. Presently, when you remotely drive that stick to zero(i.e. associate with ground/or pull-down), at exactly that point it will be perused as 0. In any case, on the off chance that you design stick as tri-state. At that point stick goes into condition of high impedance. We can state, it is currently basically associated with contribution of some Op-Amp inside the uC and no other circuit is driving it from uC. Along these lines stick has high impedance. For this situation, if stick is left gliding (i.e. kept detached) then even little static charge show on encompassing items can change rationale condition of stick. In the event that you attempt to peruse relating bit in stick enroll, its state can’t be anticipated. This may make your program go haywire, on the off chance that it relies on upon contribution from that specific stick.
In this manner while, taking contributions from pins/utilizing smaller scale changes to take include, constantly empower pull-up resistors on info pins.
NOTE: while utilizing on-chip ADC, ADC port pins must be designed as tri-expressed information.
3.3 GSM (Global System for Mobile correspondences):
GSM (Global System for Mobile correspondences) is a cell system, which implies that cell phones associate with it via scanning for cells in the prompt region. GSM systems work in four diverse recurrence ranges. Most GSM systems work in the 900 MHz or 1800 MHz groups. A few nations in the Americas utilize the 850 MHz and 1900 MHz groups in light of the fact that the 900 and 1800 MHz recurrence groups were at that point assigned. The rarer 400 and 450 MHz recurrence groups are appointed in a few nations, where these frequencies were beforehand utilized for original frameworks.
GSM-900 utilizations 890–915 MHz to send data from the portable station to the base station (uplink) and 935–960 MHz for the other bearing (downlink), giving 124 RF channels (channel numbers 1 to 124) separated at 200 kHz. Duplex dispersing of 45 MHz is utilized. In a few nations the GSM-900 band has been stretched out to cover a bigger recurrence extend. This ‘broadened GSM’, E-GSM, utilizes 880–915 MHz (uplink) and 925–960 MHz (downlink), including 50 channels (channel numbers 975 to 1023 and 0) to the first GSM-900 band. Time division multiplexing is utilized to permit eight full-rate or sixteen half-rate discourse channels per radio recurrence channel. There are eight radio timeslots (giving eight burst periods) gathered into what is known as a TDMA outline. Half rate directs utilize interchange outlines in the same timeslot. The channel information rate is 270.833 kbit/s, and the casing span is 4.615 ms.
3.3.2 GSM ADVANTAGES:
GSM additionally spearheaded an ease, to the system bearer, contrasting option to voice calls, the Short t message benefit (SMS, likewise called “content informing”), which is currently upheld on other versatile benchmarks also. Another favorable position is that the standard incorporates one overall Emergency phone number, 112. This makes it less demanding for global explorers to interface with crisis administrations without knowing the neighborhood crisis number.
3.3.3 THE GSM NETWORK:
GSM gives proposals, not necessities. The GSM particulars characterize the capacities and interface prerequisites in detail yet don’t address the equipment. The GSM system is isolated into three noteworthy frameworks: the exchanging framework (SS), the base station framework (BSS), and the operation and emotionally supportive network (OSS).
Fig 3.3.1.GSM Block diagram
3.3.4 THE SWITCHING SYSTEM:
The exchanging framework (SS) is in charge of performing call handling and endorser related capacities. The exchanging framework incorporates the accompanying useful units.
Home area enroll (HLR): The HLR is a database utilized for capacity and administration of memberships. The HLR is viewed as the most essential database, as it stores perpetual information about supporters, including an endorser’s administration profile, area data, and action status. At the point when an individual purchases a membership from one of the PCS administrators, he or she is enrolled in the HLR of that administrator.
Mobile administrations exchanging focus (MSC): The MSC plays out the communication exchanging elements of the framework. It controls calls to and from other phone and information frameworks. It additionally performs such capacities as toll ticketing, arrange interfacing, regular channel flagging, and others.
Visitor area enroll (VLR): The VLR is a database that contains brief data about endorsers that is required by the MSC keeping in mind the end goal to administration going by supporters. The VLR is constantly coordinated with the MSC. At the point when a portable station meanders into another MSC region, the VLR associated with that MSC will ask for information about the versatile station from the HLR. Afterward, if the portable station makes a call, the VLR will have the data required for call setup without interrogating the HLR each time.
Authentication focus (AUC): A unit called the AUC gives validation and encryption parameters that confirm the client’s character and guarantee the privacy of each call. The AUC shields organize administrators from various sorts of extortion found in today’s cell world.
Equipment character enroll (EIR): The EIR is a database that contains data about the personality of portable hardware that keeps calls from stolen, unapproved, or inadequate versatile stations. The AUC and EIR are executed as remain solitary hubs or as a joined AUC/EIR hub.
3.3.5 THE BASE STATION SYSTEM (BSS):
All radio-related capacities are performed in the BSS, which comprises of base station controllers (BSCs) and the base handset stations (BTSs).
BSC: The BSC gives all the control capacities and physical connections between the MSC and BTS. It is a high-limit switch that gives capacities, for example, handover, cell design information, and control of radio recurrence (RF) control levels in base handset stations. Various BSCs are served by a MSC. BTS: The BTS handles the radio interface to the portable station. The BTS is the radio hardware (handsets and recieving wires) expected to benefit every cell in the system. A gathering of BTSs are controlled by a BSC.
The Operation and Support System
The operations and upkeep focus (OMC) is associated with all hardware in the changing framework and to the BSC. The execution of OMC is known as the operation and emotionally supportive network (OSS). The OSS is the practical substance from which the system administrator screens and controls the framework. The reason for OSS is to offer the client financially savvy bolster for unified, local and nearby operational and upkeep exercises that are required for a GSM arrange. An imperative capacity of OSS is to give a system outline and bolster the support exercises of various operation and upkeep associations.
Extra Functional Elements
Message focus (MXE): The MXE is a hub that gives coordinated voice, fax, and information informing. In particular, the MXE handles short message benefit, cell communicate, phone message, fax mail, email, and warning.
Mobile benefit hub (MSN): The MSN is the hub that handles the versatile keen system (IN) administrations.
Gateway portable administrations exchanging focus (GMSC): An entryway is a hub used to interconnect two systems. The portal is frequently actualized in a MSC. The MSC is then alluded to as the GMSC.
GSM between working unit (GIWU): The GIWU comprises of both equipment and programming that gives an interface to different systems for information correspondences. Through the GIWU, clients can substitute amongst discourse and information amid a similar call. The GIWU equipment hardware is physically situated at the MSC/VLR.
3.3.6 GSM NETWORK AREAS:
The GSM system is comprised of geographic zones. As appeared in cry figure, these ranges incorporate cells, area zones (LAs), MSC/VLR benefit regions, and open land versatile system (PLMN) regions.
Fig 3.3.2.GSM Network Areas
The cell is the territory given radio scope by one base handset station. The GSM organize distinguishes every cell through the cell worldwide personality (CGI) number relegated to every cell. The area range is a gathering of cells. It is the zone in which the supporter is paged. Every LA is served by at least one base station controllers, yet just by a solitary MSC Each LA is doled out an area zone character (LAI) number.
MSC/VLR benefits territories:
A MSC/VLR benefit range speaks to the piece of the GSM organize that is secured by one MSC and which is reachable, as it is enlisted in the VLR of the MSC.
PLMN benefit territories:
The PLMN benefit range is a territory served by one system administrator.
3.3.7 GSM SPECIFICATIONS:
Determinations for various individual correspondence administrations (PCS) frameworks fluctuate among the diverse PCS systems. Recorded underneath is a portrayal of the details and qualities for GSM.
Frequency band: The recurrence extend indicated for GSM is 1,850 to 1,990 MHz (versatile station to base station).
Duplex separate: The duplex separation is 80 MHz. Duplex separation is the separation between the uplink and downlink frequencies. A channel has two frequencies, 80 MHz separated.
Channel detachment: The partition between neighboring bearer frequencies. In GSM, this is 200 kHz.
Modulation: Modulation is the way toward sending a flag by changing the qualities of a bearer recurrence. This is done in GSM through Gaussian least move keying (GMSK).
Transmission rate: GSM is an advanced framework with an over-the-air bit rate of 270 kbps.
Access strategy: GSM uses the time division numerous get to (TDMA) idea. TDMA is a procedure in which a few distinct calls may have a similar bearer. Each call is relegated a specific schedule vacancy.
Speech coder: GSM utilizes straight prescient coding (LPC). The motivation behind LPC is to decrease the bit rate. The LPC gives parameters to a channel that impersonates the vocal tract. The flag goes through this channel, abandoning a leftover flag. Discourse is encoded at 13 kbps.
3.3.8 GSM SUBSCRIBER SERVICES:
Double tone multi recurrence (DTMF): DTMF is a tone flagging plan regularly utilized for different control purposes by means of the phone system, for example, remote control of a voice-mail. GSM underpins full-starting DTMF.
Copy Assemble III—GSM bolsters CCITT Group 3 copy. As standard fax machines are intended to be associated with a phone utilizing simple flags, an uncommon fax converter associated with the trade is utilized as a part of the GSM framework. This empowers a GSM–connected fax to speak with any simple fax in the system.
Short message benefits: A helpful office of the GSM system is the short message benefit. A message comprising of a most extreme of 160 alphanumeric characters can be sent to or from a versatile station. This administration can be seen as a propelled type of alphanumeric paging with various points of interest. On the off chance that the supporter’s versatile unit is controlled off or has left the scope zone, the message is put away and offered back to the endorser when the portable is fueled on or has reappeared the scope zone of the system. This capacity guarantees that the message will be gotten.
Cell Communicate: A variety of the short message administration is the cell communicate office. A message of a most extreme of 93 characters can be communicate to every versatile endorser in a specific geographic territory. Run of the mill applications incorporate movement blockage notices and reports on mishaps.
Phone message: This administration is really a voice-mail inside the system, which is controlled by the supporter. Calls can be sent to the endorser’s voice message box and the supporter checks for messages by means of an individual security code.
Fax mail: With this administration, the endorser can get fax messages at any fax machine. The messages are put away in an administration focus from which they can be recovered by the supporter by means of an individual security code to the coveted fax number.
3.3.9 SUPPLEMENTARY SERVICES:
GSM underpins an extensive arrangement of supplementary administrations that can supplement and bolster both communication and information administrations.
Call sending: This administration gives the endorser the capacity to forward approaching calls to another number if the called versatile unit is not reachable, on the off chance that it is occupied, if there is no answer, or if call sending is permitted unequivocally.
Excepting of active calls: This administration makes it feasible for a portable endorser of keep every single active call.
Excepting of approaching calls: This capacity permits the endorser of avoid approaching calls. The accompanying two conditions for approaching call excepting exist: uncovering of every single approaching call and notwithstanding of approaching calls when meandering outside the home PLMN.
Exhortation of charge (AoC): The AoC benefit gives the portable supporter a gauge of the call charges. There are two sorts of AoC data: one that furnishes the supporter with a gauge of the bill and one that can be utilized for quick charging purposes. AoC for information calls is given on the premise of time estimations.
Call hold: This administration empowers the endorser of intrude on a progressing call and afterward in this way re-build up the call. The call hold administration is just material to typical communication.
Call holding up: This administration empowers the versatile endorser of be advised of an approaching call amid a discussion. The endorser can reply, dismiss, or overlook the approaching call. Call holding up is pertinent to all GSM broadcast communications administrations utilizing a circuit-exchanged association.
Multiparty benefit: The multiparty benefit empowers a versatile supporter of build up a multiparty discussion—that is, a synchronous discussion in the vicinity of three and six endorsers. This administration is just pertinent to ordinary communication.
Calling line distinguishing proof introduction/confinement: These administrations supply the called party with the incorporated administrations computerized organize (ISDN) number of the calling party. The confinement benefit empowers the calling gathering to limit the introduction. The confinement abrogates the introduction.
Shut client bunches (CUGs): CUGs are for the most part practically identical to a PBX. They are a gathering of supporters who are prepared to do just calling themselves and certain numbers.
3.3.10 MAIN AT COMMANDS:
“AT summon set for GSM Mobile Equipment” portrays the Main AT orders to impart by means of a serial interface with the GSM subsystem of the telephone.
AT summons are guidelines used to control a modem. AT is the contraction of Attention. Each order line begins with “AT” or “at”. That is the reason modem summons are called AT orders. A hefty portion of the orders that are utilized to control wired dial-up modems, for example, ATD (Dial), ATA (Answer), ATH (Hook control) and ATO (Return to online information state), are additionally upheld by GSM/GPRS modems and cell phones. Other than this basic AT charge set, GSM/GPRS modems and cell phones bolster an AT order set that is particular to the GSM innovation, which incorporates SMS-related summons like AT+CMGS (Send SMS message), AT+CMSS (Send SMS message from capacity), AT+CMGL (List SMS messages) and AT+CMGR (Read SMS messages).
Take note of that the beginning “AT” is the prefix that illuminates the modem about the begin of a summon line. It is not some portion of the AT summon name. For instance, D is the real AT charge name in ATD and +CMGS is the real AT summon name in AT+CMGS. In any case, a few books and sites utilize them reciprocally as the name of an AT summon.
Here are a portion of the errands that should be possible utilizing AT charges with a GSM/GPRS modem or cell phone:
3.3.11 Minimum Functionality Mode
Least usefulness mode decreases the usefulness of the GSM Modem to a base and, hence, limits the present utilization to the most reduced level. This mode is set with the “AT+CFUN” order which gives the decision of the usefulness levels <fun>=0，1，4
0: least usefulness;
1: full usefulness (default);
4: cripple telephone both transmit and get RF circuits;
On the off chance that GSM MODEM has been set to least usefulness by “AT+CFUN=0”, the RF capacity and SIM card capacity will be shut. For this situation, the serial port is as yet open, yet all AT charges correlative with RF capacity or SIM card capacity won’t be available.
On the off chance that GSM MODEM has been set by “AT+CFUN=4”, the RF capacity will be shut, the serial port is as yet dynamic. For this situation all AT orders correlative with RF capacity won’t be open.
After GSM MODEM has been set by “AT+CFUN=0” or “AT+CFUN=4”, it can come back to full usefulness by “AT+CFUN=1”.
For itemized data about “AT+CFUN”, please allude to report.
Perusing a SMS message from the Inbox:
To peruse the primary SMS from the inbox send the summon AT+CMGL=1; trailed by . The modem will answer with the content of the principal SMS in the inbox alongside senders versatile number and date and time.
To peruse the second SMS from the inbox send the order AT+CMGL=2; trailed by . The modem will answer with the content of the second SMS in the inbox alongside senders versatile number and date and time.
… et cetera. The most extreme number of SMS messages in the inbox relies on upon the SIMCARD you have put in the modem. To peruse every one of the SMS messages from the inbox send the summon AT+CMGL=ALL; trailed by . The modem will answer with the content, senders number, timestamp of the every one of the messages in the inbox in one shot.
Sending SMS message from SIM900:
To send SMS from SIM300 send the order AT+CMGS=8332925425; trailed by/r/n and after that the message content and afterward the Ascii code of Ctrl^Z character which is 0x1A;
ex: To send “Hi” to 8332925425 portable number
AT+CMGS=8332925425; trailed by
Hi Ctrl^Z Ascii code 0x1A took after by (Ascii code for is 0x0A and Ascii code for is 0x0D
Erasing a SMS message from the Inbox:
To erase the primary message from the inbox send the summon AT+CMGD=1; trailed by . The modem will erase the main message in the inbox.
To erase the second message from the inbox send the summon AT+CMGD=2; trailed by . The modem will erase the second message in the inbox.
Calling to a number utilizing SIM300:
To call to a number send the order ATD took after by the portable number and carriage return.
To call the portable number 8332925425 send the charge as,
Hanging up a bring in SIM300:
To hang up a ringing call or a bring in advance send the order ATH; trailed via carriage return
ATH; Recieving a bring in SIM300:
To get a ringing call, Send the order ATA; trailed via carriage return
ATA; Finding the quantity of the approaching bring in SIM300:
To get the quantity of the approaching call you have to empower the Caller Line Identification in SIM900.
To empower the approaching guest line distinguishing proof issue the order AT+CLIP=1 took after via carriage return
When you issue this charge, any approaching call will be informed in the accompanying arrangement,
Here +8332925425 is the quantity of the approaching call.
3.3.12 SIM 900
This is a GSM/GPRS-good Quad-band mobile phone, which takes a shot at a recurrence of 850/900/1800/1900MHz and which can be utilized to get to the Internet, as well as for oral correspondence (gave that it is associated with an amplifier and a little uproarious speaker) and for SMSs. Remotely, it would appear that a major bundle (0.94 inches x 0.94 inches x 0.12 inches) with L-formed contacts on four sides so they can be patched both as an afterthought and at the base. Inside, the module is overseen by an AMR926EJ-S processor, which controls telephone correspondence, information correspondence (through a coordinated TCP/IP stack), and (through a UART and a TTL serial interface) the correspondence with the circuit interfaced with the mobile phone itself.
The processor is additionally responsible for a SIM card (3 or 1,8 V) which should be joined to module. Also, the GSM900 gadget incorporates a simple interface, an A/D converter, a RTC, a SPI transport, an I²C, and a PWM module. The radio segment is GSM stage 2/2+ perfect and is either class 4 (2 W) at 850/900 MHz or class (1 W) at 1800/1900 MHz The TTL serial interface is in control not just of imparting every one of the information in respect to the SMS effectively got and those that come in amid TCP/IP sessions in GPRS (the information rate is controlled by GPRS class 10: max. 85,6 kbps), additionally of getting the circuit summons (for our situation, originating from the PIC overseeing the remote control) that can be either AT standard or AT-upgraded SIM Com sort.
3.4 VOLTAGE REGULTOR:
7805 is a voltage controller coordinated circuit. It is an individual from 78xx arrangement of settled direct voltage controller ICs. The voltage source in a circuit may have vacillations and would not give the settled voltage yield. The voltage controller IC keeps up the yield voltage at a steady esteem. The xx in 78xx shows the settled yield voltage it is intended to give. 7805 gives +5V controlled power supply. Capacitors of appropriate qualities can be associated at info and yield pins relying on the particular voltage levels.
3.4.2 IC 7805 RATING:
Input voltage run 7V-35V
Current rating Ic = 1A
Output voltage run VMax=5.2V
3.4.3 PIN DIAGRAM:
Fig.3.4.1.Pin diagram of 7805
3.4.4 PIN DESCRIPTION OF 7805:
|1||INPUT||Input voltage (7V-35V)||In this pin of the IC positive unregulated voltage is
given in regulation.
|2||GROUND||Ground (0V)||In this pin where the ground is given. This pin is neutral
for equally the input and output.
|3||OUTPUT||Regulated output; 5V (4.8V-5.2V)||The output of the regulated 5V volt is taken out
at this pin of the IC regulator.
Table.3.4.1.Pin Description of 7805
3.4.5 Inner Circuit of 7805:
Fig.3.4.2.Inner circuit of 7805
The distinction between the information and yield voltage shows up as warmth. The more prominent the contrast between the information and yield voltage, the more warmth is produced. In the event that an excessive amount of warmth is created, through high information voltage, the controller can overheat. On the off chance that the controller does not have a warmth sink to disseminate this warmth, it can be pulverized and breakdown. Henceforth, it is fitting to restrain the voltage to a most extreme of 2-3 volts higher than the yield voltage. So the two alternatives are, plan your circuit so that the information voltage going into the controller is constrained to 2-3 volts over the yield directed voltage or place a proper warmth sink that can proficiently disperse warm.
7805 is not extremely productive and has drop out voltage issues. A considerable measure of vitality is squandered as warmth. On the off chance that you will be utilizing a warmth sink, you better figure the warmth sink measure appropriately. The beneath equation ought to help in deciding suitable heat sink estimate for such applications.
Warm produced = (input voltage – 5) x yield current
On the off chance that we have a framework with information 15 volts and yield current required is .5 amperes, we have:
(15 – 5) x 0.5 = 10×0.5 =5W;
5W vitality is being squandered as warmth, henceforth a better than average estimated heat sink plate is required to scatter this warmth. Then again, vitality really being utilized is:
(5 x 0.5Amp) = 2.5W.
So double the vitality, that is really used is squandered. Then again, if 9V is given as contribution at a similar measure of load:
(9-5) x 0.5 = 2W
2W vitality will be squandered as warmth.
Higher the info voltage, less proficient your 7805 will be.
An expected productive info voltage would be more than 7.5V.
Voltage sources in a circuit may have variances bringing about not giving settled voltage yields. Voltage controller IC keeps up the yield voltage at a steady esteem. 7805, a voltage controller incorporated circuit (IC) is an individual from 78xx arrangement of settled direct voltage controller ICs used to keep up such vacillations. The xx in 78xx shows the settled yield voltage it gives. IC 7805 gives +5 volts controlled power supply with arrangements to include warm sink also.
A sensor is a gadget that recognizes and reacts to some kind of contribution from the physical condition. The particular info could be light, warm, movement, dampness, weight, or any of an awesome number of other ecological marvels. The yield is for the most part a flag that is changed over to comprehensible show at the sensor area or transmitted electronically over a system for perusing or further handling. A sensor is a gadget that recognizes and reacts to some kind of contribution from the physical condition. The particular information could be light, warm, movement, dampness, weight, or any of an awesome number of other ecological wonders. The yield is by and large a flag that is changed over to intelligible show at the sensor area or transmitted electronically over a system for perusing or further handling.
3.5.2 Types of sensors:
In a mercury-based glass thermometer, the information is temperature. The fluid contained grows and contracts accordingly, making the level be higher or bring down on the stamped gage, which is intelligible. An oxygen sensor in an auto’s outflow control framework distinguishes the fuel/oxygen proportion, more often than not through a substance response that creates a voltage. A PC in the motor peruses the voltage and, if the blend is not ideal, corrects the adjust. Movement sensors in different frameworks including home security lights, programmed entryways and restroom apparatuses regularly convey some sort of vitality, for example, microwaves, ultrasonic waves or light bars and identify when the stream of vitality is hindered by something entering its way. A photo sensor distinguishes the nearness of noticeable light, infrared transmission (IR), and additionally bright (UV) vitality.
3.5.2a Gas sensor MQ-5:
A gas finder is a gadget that identifies the nearness of gasses in a territory, frequently as a major aspect of a wellbeing framework. This sort of gear is utilized to distinguish a gas spill or different outflows and can interface with a control framework so a procedure can be consequently closed down. A gas indicator can sound a caution to administrators in the territory where the break is happening, giving them the chance to clear out. This kind of gadget is vital in light of the fact that there are numerous gasses that can be hurtful to natural life, for example, people or creatures.
Gas finders can be utilized to distinguish burnable, combustible and poisonous gasses, and oxygen consumption. This sort of gadget is utilized generally in industry and can be found in areas, for example, on oil apparatuses, to screen produce forms and developing advances, for example, photovoltaic. They might be utilized as a part of firefighting.
Gas spill location is the way toward distinguishing conceivably unsafe gas spills by sensors. These sensors for the most part utilize a discernable caution to ready individuals when a risky gas has been identified. Presentation to harmful gasses can likewise happen in operations, for example, painting, fumigation, fuel filling, development, exhuming of debased soils, landfill operations, entering restricted spaces, and so on.
Convenient identifiers are utilized to screen the environment around faculty and are either hand-held Common sensors incorporate flammable gas sensors, photograph ionization indicators, infrared point sensors, ultrasonic sensors, electrochemical gas sensors, and semiconductor sensors. All the more as of late, infrared imaging sensors have come into utilization. These sensors are utilized for an extensive variety of uses and can be found in mechanical plants, refineries, pharmaceutical assembling, fumigation offices, paper mash factories, airplane and ship-building offices, hazardous materials operations, squander water treatment offices, vehicles, indoor air quality testing and homes. Gas indicators can be arranged by the operation system (semiconductors, oxidation, synergist, photograph ionization, infrared, and so on.). Gas locators come bundled into two principle frame elements: compact gadgets and settled gas detectors.or worn on garments or on a belt/outfit. These gas indicators are typically battery worked. They transmit notices by means of perceptible and obvious signs, for example, cautions and blazing lights, when hazardous levels of gas vapors are recognized.
Settled sort gas finders might be utilized for recognition of at least one gas sorts. Settled sort finders are for the most part mounted close to the procedure territory of a plant or control room, or a zone to be ensured, for example, a private room. For the most part, modern sensors are introduced on settled sort mellow steel structures and a link associates the identifiers to a SCADA framework for consistent checking. A stumbling interlock can be enacted for a crisis circumstance.
Reactant globule sensors are usually used to quantify flammable gasses that present a blast peril when focuses are between the lower blast restrict (LEL) and upper blast constrain (UEL). Dynamic and reference dots containing platinum wire curls are arranged on inverse arms of a Wheatstone connect circuit and electrically warmed, up to a couple of hundred degrees C. The dynamic dot contains an impetus that permits burnable mixes to oxidize, in this manner warming the dot much further and changing its electrical resistance. The subsequent voltage contrast between the dynamic and latent dabs is corresponding to the convergence of all ignitable gasses and vapors exhibit. The tested gas enters the sensor through a sintered metal frit, which gives an obstruction to keep a blast when the instrument is conveyed into an air containing burnable gasses. Pellistors measure basically all ignitable gasses, however they are more delicate to littler atoms that diffuse through the sinter all the more rapidly. The quantifiable focus extents are regularly from a couple of hundred ppm to a couple volume percent. Such sensors are economical and strong, however require at least a couple percent oxygen in the climate to be tried and they can be harmed or repressed by mixes, for example, silicones, mineral acids, chlorinated natural mixes, and sulfur mixes.
Photograph ionization Detectors (PIDs) utilize a high-photon-vitality UV light to ionize chemicals in the inspected gas. In the event that the compound has an ionization vitality beneath that of the light photons, an electron will be shot out, and the subsequent current is relative to the convergence of the compound. Normal light photon energies incorporate 10.0 eV, 10.6 eV and 11.7 eV; the standard 10.6 eV light goes on for a considerable length of time, while the 11.7 eV light ordinarily last just a couple of months and is utilized just when no other choice is accessible. An expansive scope of mixes can be identified at levels running from a couple ppb to a few thousand ppm. Noticeable compound classes all together of diminishing affectability include: aromatics and alkyl iodides; olefins, sulfur mixes, amines, ketones, ethers, alkyl bromides and silicate esters; natural esters, alcohols, aldehydes and alkanes; H2S, NH3, PH3 and natural acids. There is no reaction to standard parts of air or to mineral acids. Real focal points of PIDs are their fantastic affectability and effortlessness of utilization; the primary impediment is that estimations are not compound-particular. As of late PIDs with pre-channel tubes have been presented that improve the specificity for such mixes as benzene or butadiene. Settled, hand-held and smaller than expected attire cut PIDs are generally utilized for modern cleanliness, hazardous materials, and natural checking.
A gas sensor is a gadget which identifies the nearness of gas in an area. This sensor interfaces with a gas to quantify its fixation. Each gas has a one of a kind breakdown voltage i.e. the electric field at which it is ionized. Sensor recognizes gasses by measuring these voltages. The centralization of the gas can be controlled by measuring the present release in the device. The MQ5 gas sensor recognizes the nearness of different gasses, for example, hydrogen, carbon monoxide, methane and LPG extending from 100ppm to 3,000ppm.For more points of interest, visits the datasheet.
Supply Voltage: 5V
Detecting focus :200-10000ppm LPG,LNG,Natural gas,Iso-butane
Analog and Digital Output
Digital Out is high or Low in light of a flexible preset edge.
Wide distinguishing extension
Stable and long life
Fast reaction and High affectability
The MQ-5 smoke sensor is delicate to smoke and to the accompanying combustible gasses:
The resistance of the sensor is diverse relying upon the kind of the gas.
The smoke sensor has an implicit potentiometer that permits you to modify the sensor computerized yield (D0) affectability as per how precise you need to distinguish gas. The voltage that the sensor yields changes appropriately to the smoke/gas level that exists in the environment. The sensor yields a voltage that is relative to the convergence of smoke/gas. The more prominent the gas fixation, the more noteworthy the yield voltage. The lower the gas focus, the lower the yield voltage.
3.5.2d Types of Gas Detection sensors: Gas Sensor (MQ2) module is helpful for gas spillage identifying (in home and industry). It can identify LPG, i-butane, and methane, and liquor, Hydrogen, smoke et cetera. In light of its quick reaction time. Estimations can be taken at the earliest opportunity. Additionally the affectability can be balanced by the potentiometer.
MQ-2 Semiconductor Sensor for Combustible Gas:
• Sensitive material of MQ-2 gas sensor is SnO2, which with lower conductivity in clean air. At the point when the objective ignitable gas exist, the sensors conductivity is more higher alongside the gas focus rising. If you don’t mind utilize straightforward electro circuit, Convert change of conductivity to compare yield flag of gas focus.
• MQ-2 gas sensor has high sensitivity to LPG, Propane and Hydrogen, likewise could be utilized to Methane and other ignitable steam, it is with ease and reasonable for various application.
This Alcohol Sensor MQ3 is appropriate for identifying liquor fixation on your breath, much the same as your basic breathalyzer. It has a high affectability and quick reaction time. Sensor gives a simple resistive yield in light of liquor focus. The drive circuit is exceptionally basic; all it needs is one resistor. A straightforward interface could be a 0-3.3V ADC.
• 5V DC or AC circuit
• Requires warmer voltage
• Operation Temperature: – 10 to 70 degrees C
• Heater utilization: under 750mW
Methane CNG Gas Sensor MQ4 is an easy to-utilize packed petroleum gas (CNG) sensor, appropriate for detecting flammable gas (made out of for the most part Methane [CH4]) fixations noticeable all around. The MQ-4 can distinguish gaseous petrol fixations somewhere in the range of 200 to 10000 ppm. This sensor has a high affectability and quick reaction time. The sensor’s yield is a simple resistance. The drive circuit is exceptionally basic; you should simply control the radiator curl with 5V, include a heap resistance, and interface the yield to an ADC.
The MQ-6 LPG – Isobutane – Propane Gas Sensor is a semiconductor gas sensor that recognizes the nearness of LPG, Isobutane, and Propane gas at focuses from 300 ppm to 10,000 ppm, a range appropriate for distinguishing gas spills. The sensor’s basic simple voltage interface requires just a single simple information stick from your microcontroller. The MQ-6 LPG – isobutane – Propane Gas Sensor recognizes the grouping of gas noticeable all around and yields its perusing as a simple voltage. The focus detecting scope of 300 ppm to 10,000 ppm is appropriate for break location. The sensor can work at temperatures from – 10 to 50°C and expends under 150 mA at 5 V.
LPG Gas Sensor (MQ6) Features:
• High Sensitivity to LPG, iso-butane, propane
• Small affectability to liquor, smoke
• Detection Range: 100 – 10,000 ppm iso-butane propane
• Fast Response Time: <10s
• Simple drive circuit
• Heater Voltage: 5.0V
• Dimensions: 18mm Diameter, 17mm High barring pins, Pins – 6mm High
MQ-7 is a Carbon Monoxide (CO) sensor, reasonable for detecting Carbon Monoxide focuses (PPM) noticeable all around. The MQ-7 sensor can quantify CO focuses extending from 20 to 2000 ppm. This sensor has a high affectability and quick reaction time. The sensor’s yield is a simple resistance. The drive circuit is extremely straight forward , only a voltage divider; you should simply control the radiator loop with 5V DC or AC , include a heap resistance, and interface the yield to an ADC or a basic OPAMP comparator.
Hydrogen Gas Sensor MQ8 for measuring the convergence of Hydrogen (H2) noticeable all around. Reasonable for measuring focuses from 100 to 10,000 ppm. Simple to actualize warmer drive and measuring circuit. This sensor is intended for long life and stable yield. Our MQ-8 Hydrogen Gas Sensor is perfect for use in a Gas Leakage Circuit for recognizing gas spills.
• High Sensitivity (MQ-8 Sensor)
• Stable and Long Life
• Detection Range: 100 – 10,000 ppm H2 (Hydrogen)
• Heater Voltage: 5.0V
• Dimensions: 18mm Diameter, 17mm High barring pins, Pins – 6mm High
Air quality sensor MQ135 for identifying an extensive variety of gasses, including NH3, NOx, liquor, benzene, smoke and CO2. Perfect for use in office or plant. MQ135 gas sensor has high affectability to Ammonia, Sulfide and Benze steam, likewise touchy to smoke and other unsafe gasses. It is with ease and especially appropriate for Air quality observing application.
• High Sensitivity
• High affectability to Ammonia, Sulfide and Benze
• Stable and Long Life
• Detection Range: 10 – 300 ppm NH3, 10 – 1000 ppm Benzene, 10 – 300 Alcohol
• Heater Voltage: 5.0V
• Dimensions: 18mm Diameter, 17mm High barring pins, Pins – 6mm High
• Long life and minimal effort
The Alcohol Sensor MQ303A is a semiconductor sensor for Alcohol identification. It has great affectability and quick reaction to liquor, reasonable for compact liquor indicator.
• High affectability
• Fast reaction and resume
• Long life and minimal effort
• Mini measure
We are instrumental in displaying subjective LPG and Natural GAS Sensor MQ5 which guarantees ideal wellbeing and security in the businesses and local part. These simple to introduce are exceedingly appropriate for identifying the nearness of petroleum gas, LPG, exhaust, smoke and town gas. The sensor in this framework is very solid and is given a straightforward drive circuit for encouraging simple operations.
• High affectability to LPG, flammable gas, town gas
• Small affectability to liquor, smoke.
• Fast reaction.
• Stable and long life
• Simple drive circuit
• Heater Voltage: 5.0V
• Dimensions: 18mm Diameter, 17mm High barring pins, Pins – 6mm High
3.6 LED (LIGHT EMITTING DIODE)
A light-producing diode (LED) is a semiconductor diode that emanates light when an electrical current is connected in the forward bearing of the gadget, as in the basic LED circuit. The impact is a type of electroluminescence where incongruous and limit range light is produced from the p-n intersection.
LEDs are generally utilized as marker lights on electronic gadgets and progressively in higher power applications, for example, spotlights and territory lighting. A LED is typically a little range (under 1 mm2) light source, regularly with optics added to the chip to shape its radiation example and aid reflection. The shade of the produced light relies on upon the creation and state of the semi leading material utilized, and can be infrared, unmistakable, or bright. Other than lighting, intriguing applications incorporate utilizing UV-LEDs for cleansing of water and sterilization of gadgets, and as a develop light to improve photosynthesis in plants.
3.6.2 BASIC PRINCIPLE:
Like an ordinary diode, the LED comprises of a chip of semi leading material impregnated, or doped, with polluting influences to make a p-n intersection. As in different diodes, current streams effectively from the p-side, or anode, to the n-side, or cathode, yet not in the turn around heading. Charge-bearers electrons and gaps stream into the intersection from cathodes with various voltages. At the point when an electron meets a gap, it falls into a lower vitality level, and discharges vitality as a photon.
The wavelength of the light radiated, and in this way its shading, relies on upon the band hole vitality of the materials shaping the p-n intersection. In silicon or germanium diodes, the electrons and gaps recombine by a non-radiative move which creates no optical emanation, on the grounds that these are aberrant band hole materials. The materials utilized for the LED have an immediate band crevice with energies relating to close infrared, noticeable or close bright light. Driven advancement started with infrared and red gadgets made with gallium arsenide. Propels in materials science have made conceivable the generation of gadgets with ever-shorter wavelengths, creating light in an assortment of hues. LEDs are generally based on a n-sort substrate, with a terminal connected to the p-sort layer kept on its surface. P-sort substrates, while less normal, happen also. Numerous business LEDs, particularly GaN/InGaN, likewise utilize sapphire substrate.
Fig.3.6.1.Basic principle of LED
3.6.3 LED DISPLAY TYPES:
- Bar graph
- Seven segment
- Star burst
- Dot matrix
Basic LED types:
Fig 3.6.2. Led Types
Diverse estimated LEDs. 8 mm, 5mm and 3 mm
These are for the most part amazing utilized as pointers, and they come in different size bundles:
• surface mount
• 2 mm
• 3 mm (T1)
• 5 mm (T1³⁄₄)
• 10 mm
• Other sizes are additionally accessible, however less normal.
Normal bundle shapes:
• Round, arch top
• Round, level top
• Rectangular, level top (regularly found in LED structured presentation shows)
• Triangular or square, level top
The embodiment may likewise be clear or semi murky to enhance difference and survey edge.
There are three principle classifications of smaller than expected single bite the dust LEDs:
• Low current — ordinarily appraised for 2 mA at around 2 V (roughly 4 mW utilization).
• Standard — 20 mA LEDs at around 2 V (roughly 40 mW) for red, orange, yellow and green, and 20 mA at 4–5 V (around 100 mW) for blue, violet and white.
• Ultra-high yield — 20 mA at roughly 2 V or 4–5 V, intended for review in direct daylight.
Five-and twelve-volt LEDs
These are smaller than normal LEDs joining an arrangement resistor, and might be associated specifically to a 5 V or 12 V supply.
Blazing LEDs are utilized as consideration looking for pointers where it is coveted to stay away from the intricacy of outside gadgets. Blazing LEDs look like standard LEDs yet they contain a coordinated multi vibrator circuit inside which makes the LED streak with a run of the mill time of one moment. In diffused focal point LEDs this is obvious as a little dark dab. Most glimmering LEDs produce light of a solitary shading, however more complex gadgets can streak between numerous hues and even blur through a shading succession utilizing RGB shading blending.
High power LEDs
High power LEDs from lumileds mounted on a star formed warmth sink High power LEDs (HPLED) can be driven at more than one ampere of current and give out a lot of light. Since overheating decimates any LED the HPLEDs must be exceedingly effective to limit overabundance warm, besides they are regularly mounted on a warmth sink to take into consideration warm dispersal. On the off chance that the warmth from a HPLED is not expelled the gadget will wear out in seconds.
A solitary HPLED can frequently supplant a brilliant globule in a spotlight or be set in an exhibit to frame an effective LED light. LEDs have been produced that can run specifically from mains control without the requirement for a DC converter. For every half cycle some portion of the LED diode transmits light and part is dim, and this is switched amid the following half cycle. Current effectiveness is 80 lm/W..
A “bi-shading LED” is really two unique LEDs in one case. It comprises of two bites the dust associated with a similar two leads however in inverse headings. Current stream in one course creates one shading, and current the other way delivers the other shading. Substituting the two hues with adequate recurrence causes the presence of a third shading. A “tri-shading LED” is likewise two LEDs in one case, however the two LEDs are associated with discrete leads so that the two LEDs can be controlled autonomously and lit at the same time.
RGB LEDs contain red, green and blue producers, by and large utilizing a four-wire association with one normal (anode or cathode). The Taiwanese LED maker Ever light has presented a 3 watt RGB bundle fit for driving each bite the dust at 1 watt.
Driven showcases are accessible in seven-fragment and starburst arrange. Seven-portion shows handle all numbers and a constrained arrangement of letters. Starburst presentations can show all letters. Seven-fragment LED showcases were in across the board use in the 1980s, yet expanding utilization of fluid precious stone presentations, with their lower control utilization and more noteworthy show adaptability, has diminished the prominence of numeric and alphanumeric LED shows.
- Car applications with LEDS
- Instrument Panels and Switches, Courtesy Lighting, CHMSL, Rear Stop/Turn/Tai, Retrofits, New Turn/Tail/Marker Lights.
- Customer hardware and general sign
- Family unit machines, VCR/DVD/Stereo/Audio/Video gadgets, Toys/Games Instrumentation, Security Equipment, Switches.
- Enlightenment with LEDs
- Design Lighting, Signage (Channel Letters), Machine Vision, Retail Displays, Emergency Lighting (Exit Signs), Neon and globule Replacement, Flashlights, Accent Lighting – Pathways, Marker Lights.
- Sign applications with LEDs
- Full Color Video, Monochrome Message Boards, Traffic/VMS, Transportation – Passenger Information.
- Flag application with LEDs
- Movement, Rail, Aviation, Tower Lights, Runway Lights, Emergency/Police Vehicle Lighting.
- Versatile applications with LEDs
- Cell Phone, PDA’s, Digital Cameras, Lap Tops, General Backlighting.
- Photograph sensor applications with LEDs
- Medicinal Instrumentation, Bar Code Readers, Color& Money Sensors, Encoders, Optical Switches, Fiber Optic Communication.
A standard serial interface for PC, RS232C, requires negative rationale, i.e., rationale 1 is – 3V to – 12V and rationale 0 is +3V to +12V. To change over TTL rationale, say, TxD and RxD pins of the microcontroller subsequently require a converter chip. A MAX232 chip has for quite some time been utilizing as a part of numerous microcontrollers loads up. It is a double RS232 collector/transmitter that meets all RS232 particulars while utilizing just +5V control supply. It has two installed charge pump voltage converters which create +10V to – 10V power supplies from a solitary 5V supply. It has four level interpreters, two of which are RS232 transmitters that change over TTL/CMOS input levels into +9V RS232 yields. The other two level interpreters are RS232 recipients that change over RS232 contribution to 5V. Run of the mill MAX232 circuit is demonstrated as follows.
Fig.3.7.1.Pin diagram of MAX 232
1. Works With Single 5-V Power Supply
2. LinBiCMOSE Process Technology
3. Two Drivers and Two Receivers
4.±30-V Input Levels
5. Low Supply Current . 8 mA Typical
6. Meets or Exceeds TIA/EIA-232-F and ITU
7. Intended to be Interchangeable With
9. ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015
10. Bundle Options Include Plastic
Little Outline (D, DW) Packages and
Standard Plastic (N) DIPs
A standard serial interfacing for PC, RS232C, requires negative rationale, i.e., rationale “1” is – 3V to – 12V and rationale “0” is +3V to +12V. To change over a TTL rationale, say, TxD and RxD pins of the uC chips, in this manner require a converter chip. A MAX232 chip has for quite some time been utilizing as a part of numerous uC loads up. It gives 2-channel RS232C port and requires outer 10uF pacitors. Deliberately check the extremity of capacitor when binding the board. A DS275 be that as it may, no need outer capacitor and littler. Either circuit can be utilized with no issues.
In this chapter all the components related to the project are studied and along with the description specifications related to each component is studied which helps in giving the input and controlling the various fluctuations that occur in case of the circuit processing. And in this the image of each and every component is displayed which helps in understanding every pin along with the pin description
4.1 SOFTWARE IMPLEMENTED:
AVR is a group of microcontrollers created by Atmel starting in 1996. These are modified Harvard engineering 8-bit RISC single-chip microcontrollers. AVR was one of the principal microcontroller families to use on-chip flash memory for program stockpiling, rather than one-time programmable ROM, EPROM, or EEPROM utilized by different microcontrollers at the time.AVR microcontrollers find numerous applications as inserted frameworks they are additionally utilized as a part of the Micro controller line of open source load up plans.
4.1.1 Device design
Streak, EEPROM, and SRAM are altogether incorporated onto a solitary chip, expelling the requirement for outer memory in many applications. A few gadgets have a parallel outer transport choice to permit including extra information memory or memory-mapped gadgets. All gadgets have serial interfaces, which can be utilized to associate bigger serial EEPROMs or blaze chips.
4.1.2 Program memory
Program guidelines are put away in non-unstable blaze memory. In spite of the fact that the MCUs are 8-bit, every direction takes maybe a couple 16-bit words. The span of the program memory is typically demonstrated in the naming of the gadget itself (e.g., the ATmega64x line has 64 KB of glimmer, while the ATmega32x line has 32 KB).There is no arrangement for off-chip program memory; all code executed by the AVR center must dwell in the on-chip streak. In any case, this constraint does not have any significant bearing to the AT94 FPSLIC AVR/FPGA chips.
4.2 Internal registers
The AVRs have 32 single-byte registers and are delegated 8-bit RISC gadgets.
In the tinyAVR and megaAVR variations of the AVR engineering, the working registers are mapped in as the initial 32 memory addresses (000016–001F16), trailed by 64 I/O registers (002016–005F16). In gadgets with numerous peripherals, these registers are trailed by 160 “developed I/O” registers, just available as memory-mapped I/O (006016–00FF16).
Real SRAM begins after these enroll areas, at address 006016 or, in gadgets with “expanded I/O”, at 010016.
Despite the fact that there are separate tending to plans and upgraded opcodes for getting to the enroll document and the initial 64 I/O enlists, all can likewise be tended to and controlled as though they were in SRAM.
The extremely littlest of the tiny AVR variations utilize a decreased engineering with just 16 registers (r0 through r15 are precluded) which are not addressable as memory areas. I/O memory starts at address 000016, trailed by SRAM. Furthermore, these gadgets have slight deviations from the standard AVR guideline set. Most prominently, the immediate load/store guidelines (LDS/STS) have been decreased from 2 words (32 bits) to 1 word (16 bits), constraining the aggregate direct addressable memory (the total of both I/O and SRAM) to 128 bytes. Then again, the aberrant load direction’s (LD) 16-bit deliver space is extended to likewise incorporate non-unstable memory, for example, Flash and arrangement bits; in this way, the LPM guideline is superfluous and discarded.
In the XMEGA variation, the working register document is not mapped into the information address space; in that capacity, it is impractical to treat any of the XMEGA’s working registers just as they were SRAM. Rather, the I/O registers are mapped into the information address space beginning at the absolute starting point of the address space. Also, the measure of information deliver space committed to I/O registers has developed generously to 4096 bytes (000016–0FFF16). Likewise with past eras, in any case, the quick I/O control directions can just achieve the initial 64 I/O enroll areas (the initial 32 areas for bitwise guidelines). Taking after the I/O enrolls, the XMEGA arrangement puts aside a 4096 byte scope of the information address space, which can be utilized alternatively to map the inside EEPROM to the information address space (100016–1FFF16). The real SRAM is situated after these extents, beginning at 200016.
Each GPIO port on a little or mega AVR drives up to eight sticks and is controlled by three 8-bit registers: DDRx, PORTx and PINx, where x is the port identifier.
• DDRx: Data Direction Register arranges the pins as either sources of info or yields.
• PORTx: Output port enroll. Sets the yield an incentive on pins arranged as yields. Empowers or cripples the draw up resistor on pins arranged as sources of info.
• PINx: Input enlist, used to peruse an info flag. On a few gadgets, this enroll can be utilized for stick flipping: composing a rationale one to a PINx bit flips the comparing bit in PORTx, independent of the setting of the DDRx bit.XmegaAVR has extra registers for push/pull, command hierarchy and pull up setups.
All AVR microcontrollers have inside EEPROM for semi-changeless information stockpiling. Like glimmer memory, EEPROM can keep up its substance when electrical power is evacuated.
In many variations of the AVR engineering, this inside EEPROM memory is not mapped into the MCU’s addressable memory space. It must be gotten to a similar way an outside fringe gadget is, utilizing extraordinary pointer registers and read/compose guidelines, which makes EEPROM get to much slower than other inner RAM. Be that as it may, a few gadgets in the Secure AVR (AT90SC) family Use an uncommon EEPROM mapping to the information or program memory, contingent upon the design. The XMEGA family additionally permits the EEPROM to be mapped into the information address space.
Since the quantity of keeps in touch with EEPROM is restricted – Atmel indicates 100,000 compose cycles in their datasheets – a very much planned EEPROM compose routine ought to think about the substance of an EEPROM address with fancied substance and just play out a real compose if the substance should be changed.
Take note of that eradicate and compose can be performed independently much of the time, byte-by-byte, which may likewise help draw out life when bits just should be set to every one of the 1s (delete) or specifically cleared to 0s (compose).
4.3 INSTRUCTION SET:
The AVR instruction set is more orthogonal than those of most eight-piece microcontrollers, specifically the 8051clones and PIC microcontrollers with which AVR contends today. In any case, it is not totally standard:
• Pointer registers X, Y, and Z have tending to abilities that are unique in relation to each other.
• Register areas R0 to R15 have more restricted tending to abilities than enlist areas R16 to R31.
• I/O ports 0 to 31 can be bit tended to, dissimilar to I/O ports 32 to 63.
• CLR influences banners, while SER does not, despite the fact that they are reciprocal guidelines. CLR set all bits to zero, and SER sets them to one. (CLR is pseudo-operation for EOR R, R; and SER is short for LDI R,FF. Math operations, for example, EOR change banners, while moves/loads/stores/branches, for example, LDI don’t.)
• Accessing read-just information put away in the program memory (streak) requires extraordinary LPM directions; the blaze transport is generally saved for guideline memory.
Also, some chip-particular contrasts influence code era. Code pointers (counting return addresses on the stack) are two bytes in length on chips with up to 128 KB of glimmer memory, yet three bytes in length on bigger chips; not all chips have equipment multipliers; chips with more than 8 KB of blaze have branch and call guidelines with longer ranges; et cetera.
The for the most part consistent guideline set makes programming it utilizing C (or even Ada) compilers genuinely direct. GCC has included AVR bolster for a long while, and that support is generally utilized. Truth be told, Atmel requested contribution from significant engineers of compilers for little microcontrollers, to decide the direction set elements that were most helpful in a compiler for abnormal state dialects.
AVRs offer an extensive variety of components:
• Multifunction, bi-directional universally useful I/O ports with configurable, developed in force resistors
• Multiple interior oscillators, including RC oscillator without outer parts
• Internal, self-programmable guideline streak memory up to 256 KB (384 KB on Xmega)
• In-framework programmable utilizing serial/parallel low-voltage restrictive interfaces or JTAG
• Optional boot code segment with autonomous bolt bits for assurance
• On-chip troubleshooting (OCD) bolster through JTAG or debugWIRE on generally gadgets
• The JTAG signals (TMS, TDI, TDO, and TCK) are multiplexed on GPIOs. These pins can be designed to work as JTAG or GPIO relying upon the setting of a wire bit, which can be modified by means of ISP or HVSP. Of course, AVRs with JTAG accompany the JTAG interface empowered.
• debugWIRE utilizes the/RESET stick as a bi-directional correspondence channel to access on-chip investigate hardware. It is available on gadgets with lower stick tallies, as it just requires one stick.
• Internal information EEPROM up to 4 KB
• Internal SRAM up to 16 KB (32 KB on Xmega)
• External 64 KB little endian information space on specific models, including the Mega8515 and Mega162.
• The outer information space is overlaid with the inward information space, to such an extent that the full 64 KB address space does not show up on the outside transport and gets to e.g. address 010016 will get to inward RAM, not the outside transport.
• In certain individuals from the Xmega arrangement, the outside information space has been improved to bolster both SRAM and SDRAM. Also, the information tending to modes have been extended to permit up to 16 MB of information memory to be straightforwardly tended to.
• AVRs for the most part don’t bolster executing code from outer memory. Some ASSPs utilizing the AVR center do bolster outer program memory.
• 8-bit and 16-bit clocks
• PWM yield (a few gadgets have an improved PWM fringe which incorporates a dead-time generator)
• Input catch that record a period stamp activated by a flag edge
• Analog comparator
• 10 or 12-bit A/D converters, with multiplex of up to 16 channels
• 12-bit D/A converters
• A assortment of serial interfaces, including
• I²C good Two-Wire Interface (TWI)
• Synchronous/non concurrent serial peripherals (UART/USART) (utilized with RS-232, RS-485, and the sky is the limit from there)
• Serial Peripheral Interface Bus (SPI)
• Universal Serial Interface (USI): a multi-reason equipment correspondence module that can be utilized to actualize a SPI, I2C or UART interface.
• Brownout identification
• Watchdog clock (WDT)
• Multiple control sparing rest modes
• Lighting and engine control (PWM-particular) controller models
• CAN controller bolster
• USB controller bolster
• Proper full-speed (12 Mbit/s) equipment and Hub controller with implanted AVR.
• Also openly accessible low-speed (1.5 Mbit/s) (HID) bit slamming programming imitations
• Ethernet controller bolster
• LCD controller bolster
• Low-voltage gadgets working down to 1.8 V (to 0.7 V for parts with implicit DC–DC upconverter)
• PicoPower gadgets
• DMA controllers and “occasion framework” fringe correspondence.
• Fast cryptography bolster for AES and DES
4.5 DEBUGGING INTERFACES:
The AVR offers a few choices for investigating, for the most part including on-chip troubleshooting while the chip is in the objective framework.
Investigate WIRE is Atmel’s answer for giving on-chip troubleshoot abilities through a solitary microcontroller stick. It is especially helpful for lower stick check parts which can’t give the four “extra” pins required for JTAG.
The Joint Test Action Group highlight gives access to on-chip investigating usefulness while the chip is running in the objective framework. JTAG permits getting to inner memory and registers, setting breakpoints on code, and single-venturing execution to watch framework conduct.
Atmel gives a progression of JTAG connectors for the AVR:
1. The Atmel-ICE is the most recent connector. It bolsters JTAG; debugWire, aWire, SPI, TPI, and PDI interfaces.
2. The JTAGICE 3 is a midrange debugger in the JTAGICE family. It bolsters JTAG, aWire, SPI, and PDI interfaces.
3. The JTAGICE mkII replaces the JTAGICE and is also estimated. The JTAGICE mkII interfaces to the PC through USB, and backings both JTAG and the more current debugWIRE interface. Various outsider clones of the Atmel JTAGICE mkII gadget began transporting after Atmel discharged the correspondence convention.
4. The AVR Dragonis a minimal effort (roughly $50) substitute for the JTAGICE mkII for certain objective parts. The AVR Dragon gives in-framework serial programming, high-voltage serial programming and parallel programming, and also JTAG or debugWIRE copying for parts with 32 KB of program memory or less. ATMEL changed the investigating highlight of AVR Dragon with the most recent firmware of AVR Studio 4 – AVR Studio 5 and now it bolsters gadgets more than 32 KB of program memory.
5. The JTAGICE connector interfaces to the PC by means of a standard serial port. Despite the fact that the JTAGICE connector has been pronounced “end-of-life” by Atmel, it is as yet bolstered in AVR Studio and different devices.
4.6. Flow chart
4.6.1. Flow chart of Micro Controller:
Port C is output
Port D is input
Pin D14 is receiver Pin
Pin D15 is transmitter pin
0 Pin 1
Port C pin C5 becomes low
Port C pin C5 Becomes high
Fig.4.2. Flowchart of microcontroller
4.6.2. Flowchart of GSM Module:
Transmitter of GSM connected to receiver of microcontroller and receiver of GSM connected to transmitter of micro controller
Message will be sent
No message will be sent
Fig. 4.3. Flowchart of GSM Module
4.6.3. Flowchart of Gas sensor:
If Gas is leaked
Pin D0 becomes high connected to micro controller
Pin D0 becomes low waits for the gas
Fig.4.4.Flow chart of Gas Sensor
RESULTS AND DISCUSSION
Thus using Micro Controller interfaced with GSM module-sim900a and MQ-5 gas sensor, one can sense the leakage of LPG gas and intimate accordingly. The designed system prevents gas leakage inside homes as well as outside homes. The system detects the LPG gas concentration in the air if it exceeds a safety level and then responds by using GSM to send an SMS to the consumer. The LED and Buzzer are activated to alert the consumer in case of gas leakage.
MQ-5 Semiconductor Sensor for Combustible Gas Sensitive material of MQ-5 gas sensor is SnO2, which with lower conductivity in clean air. When the target combustible gas exist, the sensors conductivity is higher along with the gas concentration rising. We use simple electro-circuit, convert change of conductivity to correspond output signal of gas concentration. MQ-5 gas sensor has high sensitivity to Methane, Propane and Butane and could be used to detect both Methane and Propane. The sensor could be used to detect different combustible gas especially Methane, it is with low cost and suitable for different application.As we know, security has been major issue in today’s scenario. Accidents are on increasing day by day. Here, we are talking about those accidents that are being occurred due to combustible gases, i.e., LPG, CNG. Frequently we hear, explosion in cylinder of household and vehicles. Several people have been injured and some got dead. So we are making this project for security purpose that will detect combustible gases and alert candidates.Now a day’s, LPG Gas leakage detector’s comes in the market with the LPG sensor that only senses any gas leakage and sends a SMS to the emergency no. provided to it and alerts the user via audio.
Liquid petroleum gas is generally used in houses and industries. In homes, LPG is used mainly for cooking purpose. This energy source is primarily composed of propane and butane which are highly flammable chemical compounds.LPG leaks can happen, though rarely, inside a home, commercial premises or in gas powered vehicles. Leakage of this gas can be dangerous as it enhances the risk of explosion. An odorant such as ethanethiol is added to LPG, so that leaks can be detected easily by most people. However, some people who have a reduced sense of smell may not be able to rely upon this inherent safety mechanism. In such cases, a gas leakage detector becomes vital and helps to protect people from the dangers of gas leakage. A number of research papers have been published on gas leakage detection techniques. In this project, advanced gas leakage detection technology is used. Bhopal gas tragedy is an example for accidents due to gas leakage. Gas leakage detection is not only important but controlling the leakage is also important. Liquid petroleum gas is generally used in houses.
The result of this project is that the leakage is detected and stopped within 2 seconds, after the leakage starts. This system can detect even 0.001% of leakage.
ADVANTAGES AND APPLICATIONS
- Low Cost
- Easy maintenance.
- Accessible in any location.
- Both risk and liability reduces.
- Much easier to monitor.
- The Research Work is easy to use and it gives remote indication to the user.
- The Sensor used in this Research Work has excellent sensitivity combined with a quick fast response time.
- The system is highly reliable, tamper-proof and secure.
- In the long run the maintenance cost is very less when compared to the present systems.
- It is possible to get instantaneous results and with high accuracy.
- High end security for industries even.
- High end security for museums.
- Reconfigurable to any particular industry.
- 3Design of home automation.
- Instantaneous results.
- High Accuracy
- High speed because of Wireless communication.
- More Applicable in Industries.
- LPG storage
- Gas detector
- Gas leakage detector
- Combustible gas detector
- Domestic Purpose
6.3 FUTURE SCOPE:
This project is just an example of how a gas can be controlled automatically by the use of GSM module and a gas sensor. Further this project can be extended to implement or install the gas sensors directly to the components where there is a possibility of gas leakage like components namely cylinders, pipelines etc. when all these are directly equipped to such components, there can also be a possibility to automatically blow off or turn off the gas leakage. The solution provided can be further enhanced by displaying in the LCD unit how much amount of gas is leaked. We can also incorporate the location detection feature for the gas leakage area for which SIM900 is purposely used as it comes with added feature of web interfacing by using some extra codes in the microcontroller programming.
CONCLUSION AND FUTURE SCOPE
It is very suitable for real-time and effective requirements of the high-speed data acquisition system. The MC greatly simplifies the design of peripheral circuit, and makes the whole system more flexible and extensible. Different types of sensors can be used as long as they are connected to the system. On setting the values of each sensors then the Gas leakage is known. By this way the critical situation can be avoided. The design system applies interface standard that is used for smart sensors of automatically discovering network. The sensors are not based on protocol standard. The data acquisition interface system can achieve the function of plug and play.
Finally, we conclude in recent households, the use of LPG is taking a big troll. From the use of cylinder up to the use of petroleum pipelines. The biggest threat in using this technology is security. And our project will prove to be boom for households and industries. A wide variety of leak detecting techniques is available for gas pipelines. Some techniques have been improved since their first proposal and some new ones were designed as a result of advances in sensor manufacturing and computing power. However, each detection method comes with its advantages and disadvantages. Leak detection techniques in each category share some advantages and disadvantages. For example, all external techniques which involve detection done from outside the pipeline by visual observation or portable detectors are able to detect very small leaks and the leak location, but the detection time is very long. Methods based on the
mathematical model of the pipe have good results at high flow rates while at low flow rates a mass balance based detection system would be more suitable. Hybrid systems benefiting from the real-time detection capability of a software based method and the high localization accuracy of a hardware based technique, along with other specific advantages of both approaches, seem to be the future trend in gas leak detection. Selecting from the wide variety of commercial solutions available is ultimately an action that has to be taken after assessing the needs of the system in which gas leak detection is needed.
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#define BAUD 38400 //setting up baud rate
#define bd (int)(F_CPU/16/BAUD-1) //value of UDRR to be set
void command(char*a) //function to send a string using pointers