Re: [OT] Remote Data Acquisition Programming
On Tue, 2 Sep 2003 13:20:33 +0300,
Alphonse Ogulla <firstname.lastname@example.org> wrote in message
> Hi all,
> A client has installed a number of site controllers linked to fuel
> dispensers in distant retail sites to provide automated fuelling
> services. Communication between the site controllers and a central
> front end processor (FEP) is via telephone links with modems attached
> to RS232 interfaces at both ends.
> I have a strong desire to implement a new, open and robust front end
> processor using Debian GNU/Linux primarily for automated remote data
> acquisition or data download/transfer from the controller to the FEP.
> So far, I've managed to get hold of the non-standard protocol
> specifications for communication between the FEP and site controller.
..ok, your Debian FEP box is a linux box receiving "some kinda email",
from the site controller boxes around the country? To produce bills?
..spec url? (Unless it is under a NDA)
> The communication scheme is basically the exchange of well formatted
> message blocks eg. STX - Start of text, , EOT, ACK - Acknowledgment,
> NAK, ENQ etc. with both binary and ASCII values.
> My dilemma is on how to send these messages from within a C program
..huh??? _Why_ "a C program"?
> and over a telephone link. For example, what interface should I look
> at in this case - the modem or serial port? I have read Serial port
> and Modem HOWTOs and also Serial programming for POSIX operating
..the ones over at http://tldp.org/HOWTO/HOWTO-INDEX/categories.html ?
No need to re-invent the wheel etc, you're at the very worst
just overlooking something obvious. ;-)
> systems but still can't deduce the best way to apprroach the problem.
> Are there any APIs in Linux for programming the modem/serial port or
> is making low level i/o system calls the only way out?
Here, check out the "ppp" links.
..you're also supposed to have fun, helps get better ideas:
..med vennlig hilsen = with Kind Regards from Arnt... ;-)
...with a number of polar bear hunters in his ancestry...
Scenarios always come in sets of three:
best case, worst case, and just in case.