On Thu, 29 Jan 1998, Ed Koffeman wrote:

> >Paul Haas (who -- hard as it may be to believe -- really IS pretty
> >normal)

I try to hide it.

> > has done a PIC-based web-server with great success...

The hand and temperature on my desk use a Stamp 1, which has a PIC in it.

The hottub and refrigerator use 6811s (Shh, don't tell anyone, but the
refrigerator has been replaced, and I still haven't wired up the new one.
When I do, I'll use a PIC.  The hottub sensors are still mostly working
(The ozone from the ozone generator destroyed the light sensor, so the
system always thinks the ozone generator is broken.))

> Isn't the actual server a Sun workstation, and the PICs just talk to the
> serial port with raw data?

I replaced the Sun workstations a few years ago.  I've got a 386 and a
Pentium.  The Pentium handles a little over 10,000 hits per day.  The 386
has all the serial ports, so it actually talks to the embedded computers
on my desk and in the hottub.

My very first web server used to ignore the http request entirely and
always responded with current hottub statistics.  The software just
listened to TCP/IP port 80 on the Sun workstation.  It did what I
wanted it to do, back in the dark ages of 4 years ago.

If you make the assumption that the TCP/IP stack doesn't need to run on
the webserver, then it is easy to fit a webserver on a PIC. Parsing and
generating limited HTTP is very easy, the PIC can do enough to be usefull.

If you require that the entire TCP/IP stack be on the PIC for it to be a
real webserver, then things are very difficult.  If you just want your PIC
somehow serving information to the web and recieving information from the
web, then things are easy.

--
paulh@hamjudo.com  http://www.hamjudo.com
The April 97 WebSight magazine describes me as "(presumably) normal".