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Re: Controlling an external device with elisp
From: |
upro |
Subject: |
Re: Controlling an external device with elisp |
Date: |
Mon, 05 May 2003 10:13:40 +0200 |
User-agent: |
Gnus/5.1001 (Gnus v5.10.1) Emacs/21.3 (gnu/linux) |
Ed L Cashin <cashin@cs.uga.edu> writes:
> upro <upro@gmx.net> writes:
>
>> Jonas Steverud <tvrud-usenet@spray.se> writes:
>>
>>> upro <upro@gmx.net> writes:
>>>
>>>> Now this might be a strange question, but is it possible to control an
>>>> external device, through parallel or serial port, using elisp as
>>>> programming language?
>>>
>>> It should be possible if the device has a text-based protocol and
>>> supports a tcp/ip connection. Gnus, which I use right now, does that
>>> to my ISP's newsserver.
>>>
>>> But if you mean on a lower level, if the device is stupid, like an
>>> thermometer or simple motor; I do not know.
>>>
>>> Depends on the device, a bit.
>>
>> Hi Jonas, what I meant was indeed a "stupid" device, like a selfmade
>> small circuit to switch on a light or somolar (as seen in the Coffee
>> mini-HOWTO).
>>
>> Do you think this is impossible?
>
> No, it's perfectly possible. The thing is that you can *use* the
> device from emacs but ultimately talking to hardware is a kernel
> thing. Assuming Linux, as your reference to the Coffee mini-HOWTO
> would suggest, your choices are to ...
>
> * build the circuit to recognize codes you can send using an
> existing driver
>
> e.g., you could put the device on your first serial port and
> control it from emacs by writing strings like "please turn on the
> light" or numbers like 101 to /dev/ttyS0.
>
> or
>
> * use IO primitives or write your own driver as suggested in the
> Coffee mini-HOWTO
Are these IO primitives in C? I don't really understand this.
I prefer the second suggestion, since I have very few knowledge of how
to build circtios (not to speak of how to recognize signals...)
Thank You In Advance!
>
> The former option is probably a lot easier in software; the latter is
> probably easier for you in terms of circuit design.
--
Michael
r-znvy: zvpunry.wryqra jro.qr (chg gur "@" jurer vg svgf...)
ab fcnz cyrnfr