[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Controlling an external device with elisp
From: |
Ed L Cashin |
Subject: |
Re: Controlling an external device with elisp |
Date: |
Mon, 05 May 2003 11:57:27 -0400 |
User-agent: |
Gnus/5.090014 (Oort Gnus v0.14) Emacs/21.2 (i386-debian-linux-gnu) |
upro <upro@gmx.net> writes:
> Ed L Cashin <cashin@cs.uga.edu> writes:
...
>> 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.
Yes, in fact, this is where our thread becomes off-topic in
gnu.emacs.help. It's linux-specific. Remember section 3 in the
Coffee mini-HOWTO how they mention ioperm and outb? It's that kind of
thing.
> I prefer the second suggestion, since I have very few knowledge of how
> to build circtios (not to speak of how to recognize signals...)
In that case, your work is mostly in creating a simple driver. Using
it from emacs will be easy once it's in place.
Some leads: I hear the O'Reilley book, _Linux Device Drivers_, is good
for learning how to write drivers. You can also search the kernel
sources for examples of simple device drivers and think about joining
the kernelnewbies mailing list.
--
--Ed L Cashin PGP public key: http://noserose.net/e/pgp/