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zx81
- 23rd March 2005, 23:38
I'm trying to use a U2270B to read a trasponder. This chip uses Manchester code, I don't have doubts about the decoding process, but, how can I read the pulses? I don't know how to read the signal, pulse duration, etc.

Anybody has experience with that chip? I'm using a 16F628A, but the pcb is designed for a 12C672P.

Thanks

Salutatous
- 24th March 2005, 22:48
in VAR BIT
InTrs VAR PORTB.1 'On Out of U2270b

Read:
PauseUS 130 'for Osc 8
in=Intrs
If in=1 Then
....
if in=0 Then
....
etc..

Regards

zx81
- 24th March 2005, 23:09
Thanks!!

So I suppose that a complete pulse of the code (Manchester) uses 260 microseconds.

Is this correct?

In your sample you use PAUSEUS 130 for OSC 8, but if I use the internal resonator and don't use the OSC statement on my code (or if I use a 4Mhz external resonator), I suppose that the 130 value would still correct, isn't it? I don't know if you are adjusted the value for a 8Mhz resonator instead that picbasic adjust it via OSC statement.

Regards

Salutatous
- 24th March 2005, 23:26
in manchester code:
T=560µs and T/2=280µs
and i read 64 bits
my beta prog read ok the transponder but it need to be optimized!
i can send it if you need but comments are in french :(

zx81
- 24th March 2005, 23:49
Of course, your code will help me, if you can send me to [email protected] it would be great.

If you want I can test the code on my board and colaborate with you in the optimization of the read process.

Regards

ct82
- 13th August 2005, 09:03
Can you send the code to me as well? I need it for my project. Thanks!!

Melanie
- 13th August 2005, 10:01
There are code examples already on the forum, do a SEARCH on "Manchester Code".

ct82
- 13th August 2005, 13:40
Thanks Melanie. Actually i need to read the data (manchester code) from a transponder and send it to pc using the USART feature in pic16f628A and using rs232 to interface.The problem now is i can't send the code to my pc through the microcontroller? Can you help me with that? I need it urgently. Hope to get reply from you soon!!

Melanie
- 13th August 2005, 15:06
The PBP manual is pretty explicit in using the HPWM command. A search on HPWM currently produces 56 threads many with examples of usage. Let's not ask for further examples of what's already available and been repeated many times.

NavMicroSystems
- 13th August 2005, 16:50
The PBP manual is pretty explicit in using the HPWM command. A search on HPWM currently produces 56 threads many with examples of usage. Let's not ask for further examples of what's already available and been repeated many times.


I guess what Melanie was actually trying to say is:
See Manual Section 5.30 for HSERIN and Section 5.31 for HSEROUT

A Search on HSEROUT produces 127 threads with many examples!

Melanie
- 13th August 2005, 19:53
Errr... Thanks Ralph... Brain's gone soft! Too much work and not enough party! But it's Saturday night...

Salutatous
- 18th August 2005, 09:27
The code is in your private box

Regards

ct82
- 19th August 2005, 06:05
The code will be very helpful to me.

depadua
- 5th November 2011, 02:37
Please send to me too.
Tank you