Lieven,

In addition to Dallas' excellent tech brief mentioned by
Guy Robinson, you might check the following sites, both
of which contain information about and/or code samples
for interfacing the 1-wire devices with a PIC.

http://www.ccc.nottingham.ac.uk/~cczsteve/pic84.html
http://www.phanderson.com/

The following site offers a PC-based 1-wire to serial
port system; the proprietor is PIC-friendly (he offers
Linux-based PIC programming software) and may have some
tips for what you are trying to do as well:

http://www.nexuscomputing.com/

Also, the following app note contains 8051 assembly
source code for driving a 1-wire bus off a serial port,
which would be more helpful if you were using an 8051 :-)
but at least is a code sample from Dallas... It also
contains source in C and Pascal for driving a 1-wire bus
with an 8250-style UART.

http://www.dalsemi.com/DocControl/PDFs/app74.pdf

--Bob

On Fri, Apr 30, 1999 at 02:30:34PM -0700, Lieven wrote:
> I'm working on a PIC project that talks to a Dallas 1-wire part.
> Unfortunately, I can't seem to get it to talk to me.  Attaching
> a scope shows a presence pulse but no response to my (seemingly
> properly formed and timed, per my interpretation of the 1-wire
> spec) transmission.
>
> I'm surprised to say that neither the Dallas Semiconductor site,
> nor the Microchip site, nor anyplace else I've searched on the
> web, have any code samples for an iButton or 1-wire interface.
>
> Can anyone point me to a site, or send me an example?  C, assembly,
> even pseudocode would be handy so I could confirm that my bit-level
> signaling is correct.  My project uses the deluxe 17C7xx series,
> but I'm familiar with the lower end processors as well.
>
> Thanks,
> Lieven

--
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Bob Drzyzgula                             It's not a problem
bob@drzyzgula.org                until something bad happens
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