>>From: "Lucian Copat"
>>>Thank you Ake for your posts !
>>>
>>>I think I found the problem, but remains to test this. I read now in the
>>>MCP2551 datasheet that it has a permanent dominant detection and the
>>>minimum speed is 16Kbits/sec. I was setting my speed to 10Kbits/sec. I
>>>will try now with a speed greater than 16Kbits/sec.
>>>
>>>Thank you for the links, I will give them a look too !
>
>>Have you solved the problem yet?
>>
>>Your guess is probably correct. I remember messing with the 2551 driver, 
>>and
>>not understanding why changing the input state apparently did nothing to 
>>the
>>output. I went as far as replacing the driver, until I read the datasheet
>>and realized it won't transmit a pulse over 62.5 uS long.

> The problem didn't come from the driver time, although it was an issue
> that needed to be fixed :)
>
> The problem came from the simple fact that the receiver had a frequency,
> while I was thinking it had another... It was running at 1MHz, because I
> forgot to set OSCCON register for internal oscillator and to enable PLL,
> and I was thinking that it was at 32 MHz, and so I had the wrong values
> for the BAUD control registers in CAN module. Once I fixed this problem,
> CAN went smoothly. Now I'm able to receive every message without any
> problem, without termination resistors, at 40kb/sec.

Excellent!

> I think I might be
> able to run up to 1km at this speed and without termination resistors,
> right ?

I have no idea. But you will try it and let us know, right? :)

Vitaliy 

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