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Remote Control Based on the RS232 Protocol

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A few weeks ago I was studying PIC Microcontrollers and how to interface them with the computer using the computer serial port. This was possible because many PIC Microcontrollers such as PIC16F628 and PIC16F877 has a built in UART module (Universal Asynchronous Receiver/Transmitter) that enables serial communication using the RS232 protocol.

The tutorial I used suggested the following circuit.

To explain the circuit briefly,
The PIC used is PIC16F628A. The MAX232 IC is used for the logic level translation. This is because the logic levels as well as the voltage levels on which the computer serial port and the microcontrollers work on are different.  These levels are illustrated below,

Logic levels of the computer serial port
Logic levels of the microcontrollers
The MAX232 works as an interface between the microcontroller and the computer translating these logic levels.

I'll discuss the code used for serial communication in the next post.
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Comments

  1. Harsha WijesooriyaJanuary 4, 2011 at 10:23 PM

    this is so interesting

    ReplyDelete
  2. UnknownJanuary 13, 2011 at 8:32 AM

    Remote Controls are RC5 Protocol not RS232

    ReplyDelete
  3. Thimira AmaratungaJanuary 13, 2011 at 8:51 AM

    Yes, normal remote controls use protocols like RC5 or SIRC. This is a personal project of mine to build a remote control based on the RS232 protocol.

    ReplyDelete

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