with respect to parallel port Linux drivers,

On Wed, 20 Jan 1999, Byron A Jeff wrote:

> For simple stuff to the parallel port just use the user level I/O interface
> and make the application setuid root (because I/O require root access).

True. In fact, The person working on hacking the PicStart+ protocol has
been successful capturing the data flowing on the serial line between a PC
(running windows) and the programmer. Then he could cat that data from
Linux directly to the Picstart+ and get the programmer to respond! All of
this without writing any special drivers or even needing an oscilloscope.

> BTW it may bear repeating (I haven't seen a Linux based environment discussion
> lately) that a Linux based PIC environment is doable. Last semester I had one

That's because most of the Linux based pic development discussion has
moved to the gnupic mailing list. Here lately though, the only traffic has
pretty much been gpsim release announcements.


> of my students build a parallel port based 16[CF]84 programmer that uses
> Nexus Computers picprog to program, Timo Rossi's picasm located:

> http://www.iki.fi/trossi/pic/

That is a very nice assembler. However, I would recommend gpasm instead
since it accepts mpasm formatted source files without modification:

http://reality.sgi.com/jamesb/gpasm/

> for an assembler, and I experimented with Scott Dattalo's gpsim simulator at:
>
> http://interstice.com/~sdattalo/gnupic/gpsim.html
>
> Which works really well but I think need in addition to the complicated node
> and waveform based pin simlation a really simple interface where you can just
> set a pin high or low for input.

The stimulation interface is way too complicated.... I will be addressing
this issue shortly. In the mean time however, I've begun hacking gpasm to
provide symbolic information that may be used by gpsim. In the next
release I expect to add commands that will allow one to view source and
list files and set breakpoints symbolically. Incidentally, I've also begun
devoping a gui based register viewer. I probably will not have that
available in the next gpsim release though.

> I banged out two quick light control projects over the holidays with this
> setup and was extremely happy to finally retire my PICSTART/DOSEMU based
> system that I was using earlier.
>
> Next on my project list is adding a second 16C84 based programmer with a
> serial interface which will program the rest of the PIC family.

Great! I'll be looking forward to that!

> I'm looking forward to hearing more about PIC and Linux integration here on
> the list.

Me too. However, many of us prefer to have the detailed discussions on the
GNUPIC mailing list. Go to the gnupic webpage on info how to subscribe.

http://reality.sgi.com/jamesb/gnupic/

(The traffic is 2.5 orders of magnitude lower)

Scott