Construct and Soldering Prosess

This is the soldering process for the Solar Charging Controller Circuit...

After I construct the circuit, now it is the time for soldering

PIC16F877A Microcontroller

PIC16F877A 

PIC16F778A is widely uses now and it is also famous among the beginner until all the professionals because of the FLASH Memory technology which can be write/erase within a tousand times of programming. Speed and code compression are the superiority of this risc microcontroller compared to other 8-bit microcontroller. PIC16F877A have 40 pin by 33 path of I/O. EEPROM memory makes it easier to apply microcontrollers to devices where permanent storage of various parameters is needed (codes for transmitters, motor speed, receiver frequencies, etc.). Low cost, low consumption, easy handling and flexibility make PIC16F877A applicable even in areas where microcontrollers had not previously been considered (example: timer functions, interface replacement in larger systems, coprocessor applications, etc.).In System Programmability of this chip (along with using only two pins in data transfer) makes possible the flexibility of a product, after assembling and testing have been completed. This capability can be used to create assembly-line production, to store calibration data available only after final testing, or it can be used to improve programs on finished products.

PIC16F877A Bubble Diagram

Special Microcontroller Features:

• 100,000 erase/write cycle Enhanced Flash program memory typical
• 1,000,000 erase/write cycle Data EEPROM memory typical
• Data EEPROM Retention > 40 years
• Self-reprogrammable under software control
• In-Circuit Serial Programming™ (ICSP™) via two pins
• Single-supply 5V In-Circuit Serial Programming
• Watchdog Timer (WDT) with its own on-chip RC oscillator for reliable operation
• Programmable code protection
• Power saving Sleep mode
• Selectable oscillator options
• In-Circuit Debug (ICD) via two pins

Peripheral Features:

• Timer0: 8-bit timer/counter with 8-bit prescaler
• Timer1: 16-bit timer/counter with prescaler, can be incremented during Sleep via external crystal/clock
• Timer2: 8-bit timer/counter with 8-bit period register, prescaler and postscaler
• Two Capture, Compare, PWM modules
• Synchronous Serial Port (SSP) with SPI™ (Master mode) and I2C™ (Master/Slave)
• Universal Synchronous Asynchronous Receiver
• Transmitter (USART/SCI) with 9-bit address detection
• Parallel Slave Port (PSP) – 8 bits wide with external RD, WR and CS controls (40/44-pin only)
• Brown-out detection circuitry for Brown-out Reset (BOR)

High-Performance RISC CPU:

• Only 35 single-word instructions to learn
• All single-cycle instructions except for program branches, which are two-cycle
• Operating speed: DC – 20 MHz clock input DC – 200 ns instruction cycle
• Up to 8K x 14 words of Flash Program Memory, Up to 368 x 8 bytes of Data Memory (RAM), Up to 256 x 8 bytes of EEPROM Data Memory
• Pinout compatible to other 28-pin or 40/44-pin PIC16CXXX and PIC16FXXX microcontrollers

Analog Features:

• 10-bit, up to 8-channel Analog-to-Digital Converter (A/D)
• Brown-out Reset (BOR)
• Analog Comparator module (Two analog comparators, Programmable on-chip voltage reference (VREF) module, Programmable input multiplexing from device inputs and internal voltage reference, Comparator outputs are externally accessible)

CMOS Technology:

• Low-power, high-speed Flash/EEPROM technology
• Fully static design
• Wide operating voltage range (2.0V to 5.5V)
• Commercial and Industrial temperature ranges
• Low-power consumption

Output Circuit

 1. LCD

LCD pins diagram

The most commonly used LCDs found in the market today are 1 Line, 2 Line or 4 Line LCDs which have only 1 controller and support at most of 80 characters. Most LCDs with 1 controller has 14 pins. Pin description is shown in the table below:

Character LCD pins with 1 controller

Display data RAM (DDRAM) stores display data represented in 8-bit character codes. Its extended capacity is 80 X 8 bits, or 80 characters. The area in display data RAM (DDRAM) that is not used for display can be used as general data RAM. So whatever user sends on the DDRAM is actually displayed on the LCD. For LCDs like 1x16, only 16 characters are visible, so whatever user write after 16 chars is written in DDRAM but is not visible to the user.

LED circuit connection

Above is the connection diagram of LCD in 4-bit mode, only 7 pins needed to interface with an LCD. D4 - D7 are the data pins connection and Enable and Register select are for LCD control pins. The Read/Write (RW) pin of the LCD will not be using, as the data only writing on the LCD. So, it has to be grounded permanently. If user wants to use it, then they may connect it on controller but that will only increase another pin and does not make any big difference. The unwanted data pins of LCD i.e. Vss, VEE and D0-D3 are connected to ground.

There are many reasons why use LCD in 4-bit mode instead of 8-bit. One basic reason is lesser number of pins are needed to interface LCD.

2. LED

LED Output Circuit

When OUTPUT 2 receive logic condition from the microcontroller, R10 (330kohm) will limit the current to the D3 LED. The D3 LED will on.

3. Relay Switching

Relay Switching Circuit

For the above circuit, when the base of the transistor receive any supply from the microcontroller, it will allow the 5V to the ground without active the relay. Otherwise, the relay will active and create a back e.m.f that will turn the switching from the normally open to normally close (which is turn on the Backup RCCB).

Component

I was bought the component  that i need in my project. It not all the component but the main part of this project i was bought it.

Circuit and PCB Design

I have finish to design the my schematic and PCB layout for my project Air quality monitoring system by using the EAGLE (Easily Applicable Graphical Layout Editor).

 I was try to run this schematic and it complete running and functioning (Alhamdulillah)

 schematic design

This is the PCB layout that i will print in on the board and all component will be solder on it (insyaAllah)

PCB layout

Meeting with supervisor

 August 9
I was attend first meeting with my supervisor  Tn Hj.Dr. Zainuddin bin Kornain for this semester. Show him my progress report and his give some advise and give me the idea in complate my project.

this sem i am stating to make the hardware, not just the proposal and report.............it getting hard....

The Taguchi Gas Sensor

After doing some research and some advise from Tn Hj.Dr. Zainuddin i finally choose the Taguchi gas sensor (TGS2600) to apply in this project, , TGS2600 will be chose as a gas detector due to the small size, high sensitivity and lower price compared to other gas sensor. This sensor is widely used in many sensor and detector applications.

• Why i choose TGS 2600?

1. This sensor is widely used in many applications such as in robotic machinery, smart extinguisher, aromatherapy sensing and many more. The characteristic of this sensor has been compared with the newly developed sensor for benchmarking purposes. This shows that the TGS2600 is a very reliable sensor for detecting air contaminant level in the environment.
2. The TGS 2600 has high sensitivity to low concentrations of gaseous air contaminants such as hydrogen and carbon monoxide which exist in cigarette smoke. The sensor can detect hydrogen at a level of several ppm. Figaro also offers a microprocessor (FIC02667) which contains special software for handling the sensor's signal for appliance control applications

Meeting with Supervisor

In this weeks meeting with Tn Hj.Dr. Zainuddin,  we went through the project plan i created the week previous. The project plan included the features of sensor which I wanted to include in the project and ideas about each and how i would design it. In our last discussion i agree with Sir Zainuddin idea to apply the Taguchi gas sensor in my project due to it is the good sensor

Estimating the Budget

This week i not have many class due to the public holiday. so, my friend and i went to the Jalan Pasar to survey the price of the component, estimating the exact budget for my incoming final year project and to complete the proposal report that i need to submit to my supervisor . From my surveillance,the price is reasonable and still put on my budget. Alhamdulillah, my plan will going smoothly insyaALLAH.

Gas Sensor

In my research about gas sensor, there has many kind of gas sensor in the market that can be applied in my project.

• Carbon monoxide sensor CO-AF (Portable) 

Specifications of Electronic gas sensor CO-AF:
1) Measurement range: 0-5000ppm
2) Overgas range: 10000ppm
3) Sensitivity: 55-90 nA per ppm
4) Resolution: 0.5 ppm equivalent
5) Operating range: 24 months
6) Load resistor: 10 to 47 Ω

Features of Electronic gas sensor CO-AF:
1) Leak free guarantee
2) 2 year warranty
3) Drop-in replacement for equivalent sensor
4) Sensor traceability via barcode tracking system
5) Colour coded plastic housing

Applications of Electronic gas sensor CO-AF:
Portable CO detectors 

• Combustible gases sensor TGS2610 

Description of gas sensor TGS2610: 
TGS2610-D00 uses filter material in its housing which eliminates the influence of interference gases such as alcohol, resulting in highly selective response to LP gas. This feature makes the sensor ideal for residential gas leakage detectors which require durability and resistance against interference gas. 

Specifications: 
1) Target gases : Butane, LP gas 
2) range：500 ~ 10,000 ppm 
3) sensitivity (change ratio of Rs) : 0.56 ± 0.06 
4) Circuit Voltage：5.0±0.2V DC/AC 
5) Heater Voltage：5.0±0.2V DC/AC 

Features of gas sensor TGS2610: 
1) High sensitivity to combustible gases 
2) Low power consumption 
3) High sensitivity to methane, propane and butane 
4) Long life and low cost 
5) Uses simple electrical circuit 
6) Small size 

Application of gas sensor TGS2610: 
Domestic gas leak detectors and alarms 
Portable gas detectors 

Combustible gas and vapor detection

• LED NDIR carbon dioxide CO2 Sensor C20

Dscription of carbon dioxide sensor C20: 

    An innovative High Speed, Real Time, Low Cost, Precision gas sensor using Al-In-Sb (Aluminium Indium Antimonde) NDIR LED technology. The base Mid IR solid state technology, developed by QinetiQ and licensed on a sole basis has been incorporated into an advanced CO2 sensor that is suitable for high volume manufacture and is targeted at a number of Carbon Dioxide Sensor applications. 
This Carbon Dioxide sensor is a fast, low power NDIR sensor. 

BENEFITS of carbon dioxide sensor C20: 
1) four readings per second, high accuracy 
2) easy to use: digital output, temperature compensated and linearised 
3) low power: 100mW 
4) solid state: no moving parts, no filaments 
5) wide temperature range: -25℃ to + 55℃ 
6) useful range: 0-10%(higher available) 
7) good immunity to other gases & humidity 
8) various voltages available from 3.3v to 9v 
9) 20mm package 

APPLICATIONS of carbon dioxide sensor C20: 
Modified atmospheres 
Indoor air quality 
Stowaway detection 
Cellar & gas stores 
Combustion control 
Shipping containers 
Atmospheric research 
Greenhouses 

• LED NDIR carbon dioxide CO2 Sensor C20 

Dscription of carbon dioxide sensor C20: 
    An innovative High Speed, Real Time, Low Cost, Precision gas sensor using Al-In-Sb (Aluminium Indium Antimonde) NDIR LED technology. The base Mid IR solid state technology, developed by QinetiQ and licensed on a sole basis has been incorporated into an advanced CO2 sensor that is suitable for high volume manufacture and is targeted at a number of Carbon Dioxide Sensor applications. 
This Carbon Dioxide sensor is a fast, low power NDIR sensor. 

BENEFITS of carbon dioxide sensor C20: 
1) four readings per second, high accuracy 
2) easy to use: digital output, temperature compensated and linearised 
3) low power: 100mW 
4) solid state: no moving parts, no filaments 
5) wide temperature range: -25℃ to + 55℃ 
6) useful range: 0-10%(higher available) 
7) good immunity to other gases & humidity 
8) various voltages available from 3.3v to 9v 
9) 20mm package 


APPLICATIONS of carbon dioxide sensor C20: 
Modified atmospheres 
Indoor air quality 
Stowaway detection 
Cellar & gas stores 
Combustion control 
Shipping containers 
Atmospheric research 
Greenhouses 

• CO2 Carbon Dioxide sensor TGS 4161 

Description of carbon sensor TGS4161: 
TGS4161 is a new solid electrolyte CO2 sensor which offers miniaturization and low power consumption. A range of 350~10,000ppm of carbon dioxide can be detected by TGS4161, making it ideal for indoor air control applications. 

Features of carbon sensor TGS4161: 
1) High selectivity to CO2 
2) Compact size 
3) Low dependency on humidity 
4) Long life and low cost 
5) Low power consumption 

Applications of carbon sensor TGS4161: 
1) Indoor air quality control 
2) CO2 monitors

• CO2 Carbon Dioxide sensor TGS 4160 

Description of carbon sensor TGS4160: 
TGS4160 is a new solid electrolyte CO2 sensor which offers miniaturization and low power consumption. A range of 300~5,000ppm of carbon dioxide can be detected by TGS4160, making it ideal for indoor air control applications. 

Features of carbon sensor TGS4160: 
1) High selectivity to CO2 
2) Compact size 
3) Low dependency on humidity 
4) Long life and low cost 
5) Low power consumption 

Applications of carbon sensor TGS4160: 
1) Indoor air quality control 
2) CO2 monitors 

Objective of this project

Air pollution is when the introduction of chemicals, particulate matter or biological materials starts to contaminate the air where it may cause harm and discomfort to human being and other living organisms. It also damages the natural environment and the atmosphere. The World Health Organization (W.H.O) stated that 2.4 million people died each year directly attributed by air pollution, with 1.5 million of these deaths was attributable by indoor air pollution. The Air Quality Index (AQI) which also known as the Air Pollution Index (API) or Pollutant Standard Index (PSI) is a number used by many government agencies to characterize the quality of the air at a given location. As the AQI increases, an increasingly large percentage of the population is likely to experience the increases of severe adverse health effects

Because of that, this project intends to produce new air quality monitoring system that is user-friendly in monitoring air quality continuously and efficient in prevent air pollution also reduce hazard cause of the air pollution and 

• To create new device and systems that cans automatic function so that air pollution can be monitoring time by time.
• To reduce the size of air monitoring pollution to make it as a portable unit and can be put in tiny space.
• To develop device that friendly user by give short-term warning of pollution risk to give early warning to people can make early preparation.
• To development of air quality monitoring system’s reliability estimate techniques by considering the failure and repair rate of the air monitoring component.

About Development of Air Quality monitoring System

For the first idea this project is about the development of automated  monitoring device for environmental air pollutant detection.  The main part of the device will consists of a detector,  microcontroller and timer circuit.  The gas sensor will be used to detect air contaminant level,  in which the detection through the sensor measures  in unit of part per million (ppm). A PIC Microcontroller  will be utilized to  convert the analogue signal from the sensor  into digital signal which finally displays the  result through the liquid crystal display (LCD)