Need help!!! Read 64 bit manchester code using PIC16F628A

[chentzin]

manchester 64 bit

Does anyone have idea on how to read 64 bit manchester code using PIC16F628A. I need it urgently. Thanks!!

 

[Buriedcode]

pic16f628a serial data stream

hi,

I've done a bit of work with manchester (biphase) coding.

It all depends on the datarate, and what exactly this 'manchester data' is. The 628 as far as I know can only manage 5MIPS. Also, is this a packet structure, or a continuous stream? If continuous, you'll have to do any processing between bits (manchester bits, not a data bit) which would reduce the datarate you can handle. Although, if you plan to 'over sample' the incoming stream, you could still read about 110kb/s.

If its bursty (packets) then you could just read in, decode 'on-the-fly' ie: if you receive a one, then a 0, then thats a '0' data bit, and a 0-1 is a 1. Sometimes its the other way around. A simple loop that periodically reads in, decodes, and stores. Then, between packets you can do what you want with the data.
Anything below about 500Kb/s I think can be done. I've done it.

But I assume you mean at a sensible datarate (<40kbs). In which case there are many options.

try here:
https://ww1.microchip.com/downloads/en/AppNotes/91045a.pdf
**broken link removed** - great site.
www.fpga4fun.com/10BASE-T3.html (for fpga's and ethernet, but the guy explains encoding and decoding well)

basically, just treat it as a standard serial stream. And use a timer to work out its datarate, so you know when to sample.

good luck.

Buriedcode.