THANKS for the comments thus far! I realize there are hardware approaches,
such as serial to ethernet adapters (Lantronix, etc.). I'm wondering,
though, of a purely software approach on the Windoze side. I've written a
lot of cgi scripts, and the stuff the browser sends the cgi is pretty easy
to deal with (even with a pic). The trick is to get the browser to send
that directly to the pic (through a serial port) instead of through
ethernet (or slip on the serial port). Just send the GET or POST request
out the serial port and display what comes back.

Since the exchange is all ascii, a PIC could handle it very cheaply
without having to deal with slip, ethernet, or requiring additional
hardware to deal  with ethernet. Maybe if the OS treats a com port like a
file, the URL could be
file://com1/somethingOrAnother/?parameter1=123&parameter2=456 .

Just playing around with the idea. Why convert to ethernet if we don't
need to?

Harold

> Harold Hallikainen wrote:
>> I'm wondering about a cheap and dirty way to get a Windoze GUI for PIC
projects. Is there any way to direct a URL request from a browser to a
COMM port? Say, instead of the http:// or file:// prefix, we did a
com1://
>> prefix (perhaps a URL of com1://mydevice/analog?chan=1). Instead of
sending the request out to the specified IP address over ethernet, it'd
send the GET or POST request out the specified EIA232 port. Our PIC
would
>> just respond to the request. The mydevice in the above URL would be
meaningless, though perhaps the PIC device could ignore requests not
addressed to it (not respond), allowing other devices on a tri-state or
open collector EIA232 bus to respond. I've done "open collector" EIA232
buses by having a pull-down to -12 and a diode between the driver and
the
>> bus. Any device can drive the bus positive (space condition), and the bus
>> idles at -12V (mark condition). This would be a master/slave
>> arrangement,
>> since no device gets on the bus unless asked for a response, so contention
>> would not be an issue.
>> So, any "wedge" or something that can be put on a Windoze machine so a URL
>> prefix of com1: com2: etc. would work?
>> Just kicking around the idea.
>> THANKS!
>> Harold
>
> If I understand you correctly, you might meet your needs with a
> Lantronix Xport.  It is a web server in a RJ45 connector with network on
one side and a serial port on the other.
>
> It can repsond to wiggles on the serial port and send data to you over
the network. It can even send an email.  The host machine gets a comm
port redirector program that allows you to configure the device like a
remote comm port.  An eval board is around $50 or $60US.
>
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