URGENT: 12V DC motor speed control using PIC16f877a

Hi,

I'm doing my final project for my diploma. My project title is DC motor speed control using PIC16f877a. Currently, I faced some problem in how to interface the PC-PIC-Tx/Rx.....Tx/Rx-PIC-L293D-Motor. And how to do the feedback result of optical encoder to PIC.

Basically, my project consists of 2 PIC, 433MHz RF Module with PT2262 & PT2272-L4 (Cytron), Max232, RS232 cable, 12V DC motor, Optical encoder.

I'm using assembly lang and Visual Basic.

Thank you...

You need to work them out part by part. Try do loop back from PIC to PC then controlling motor with L293D, then acquire data from opto isolator to PIC, then RF modules. Then, only combine all together. I would recommend you to use C. It will be easier compared to asm

You can try this: Microchip PIC micros and C - source and sample code

there are 3 types of c compiler that you can choose from mikroC, C18 and hi tech c

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For L293D :http://www.solarbotics.com/assets/do...tion/kit10.pdf

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and Google of course

While C is certainly appropriate, you mentioned in your first post that you were using Assembly. That is what I use with the 8-bit chips. Microchip has many application notes using Assembly code for motor control. I assumed your motor was brushed rather than brushless. Here is a link to the Microchip site with several additional links to help you.

As for the wireless control that you mention, I suggest you visit this group (http://www.edaboard.com/group146.html). Bigdogguru has put a lot of effort into assembling resources on that subject. The ones on Manchester coding may be most applicable for your project, but that is based only on a guess as to what RF links you plan to use.

John