> -----Original Message-----
> From: Tony Nixon [SMTP:Tony.Nixon@ENG.MONASH.EDU.AU]
> Sent: Friday, June 16, 2000 6:08 AM
> To:   PICLIST@MITVMA.MIT.EDU
> Subject:      Re: instructions
>
> What I am trying to do is output an 8 bit value to PortB as quick as
> possible. The data is coming from RAM at address 0x40 to 0x7F. To avoid
> the problems I had with quick succession BSF BCF instructions I had to
> do the following...
>
That is a bit of a concern to me.  I have never had problems using multiple
bit operations on an internal register, nor would I expect it, certainly not
running at 4MHz.  Port pins are a special case as they are exposed to all
the capacitive/inductive bits and pieces that you hang of them.  I might
expect this sort of thing if the PIC was grossly overclocked.  Did you try
more than one PIC/is this repeatable?

Regards

Mike Rigby-Jones