Week 10 - Week 11 (FYP II): RS232 to TTL

Objective: To create a RS232 to TTL converter circuit

Analysis/Procedure:

RS232 is an asynchronous communication protocol that lets you transmit and receive data between DTE (Data terminal Equipment) and DCE (Data Circuit Terminating Equipment) such as modem.  It  is  the  EIA/TIA  (Electronic  Industries  Alliance/  Telecommunications Industry  Association)  that  defines  physical  and  electrical  characteristics  of  the  RS -232 interface.

RS-232 is active low voltage driven interface and operates at between  -12V and +12V for which  signal  is  LOW  or  0  when  voltage  is  higher  than  +3  Volt  and  signal  is  HIGH  or  1 when voltage is lower than -3 Volt. For any voltage falling between +3 Volt and -3 Volts are considered „dead area‟ or indeterminate value. TIA defines the power level for short circuit protection  to  be  100mA,  however  most  RS-232  drivers  will  provide  lower  short  circuit protection. 

Week 7 - Week 9 (FYP II): The Microcontroller Circuit

Objective: To create a microcontroller circuit.

Analysis/Procedure:

The Peripheral Interface Controller (PIC) is the heart and the brain of this project. The PIC16f877A is a component which easy to install to a circuit board. It can be operational with voltage source from 4.0V to 5.5V. The component is very sensitive towards heat especially when soldering which could lead to component damage. Hence, a PIC housing is used. When soldering the component into a circuit board, the PIC housing must be soldered first since it is able to withstand the heat. Other electronics component needed are;

1.  Voltage regulator
2.   22pF capacitor
3. Crystal (XTAL) oscillator
4. LED
5. Male pin 

After the circuit has been completed, the Peripheral Interface Controller (PIC) need to be coded. It takes almost 2 weeks to write the coding since I have a very basic knowledge of programming. After three weeks, the microcontroller circuit is completed. However, the circuit is still need to be tested when integrating with other circuit.

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