a while ago I asked about accessing the serial port from Linux. I got a lot
of very nice answers, thanks to anyone for answering, I will publish our
results and code when the project is finished.
The "problem" now is that I have received detailed information about how
the hardware "the other guys" are about to solder speaks to the serial
port, which makes me kind of sick. It seems that there is no thought of a
standard serial RS232 handshake protocol.
The hardware expects a clock signal on the DTR pin (whenever DTR is toggled
it sends a bit), a fixed configuration signal (bit width, LSB/MSB conf,
etc) on the RTS pin, and sends the binary data on the DTR port. They
designed it so that "it's easy to program from DOS" (which is probably even
true), but I would like the machine to run under Linux, because it has to
put the gained data over a network.
The sampling frequency with which the DTR is being fed is way below a kHz,
so my former ideas about 4..5kHz sampling frequency seemed to have failed
on the hardware (the A/D chip is a cheap one, it seems). All we want to do
with it is to long-term analyze the sound/speech volume in (i.e. useage of)
a certain room here over a few weeks, the sound doesn't even have to be
recognizable. (One of the things that we have been strictly forbidden to do
is to use a soundcard, so don't ask. Strictly speaking, this is a 100%
hardware project, the PC is thought to be only there for making the data
look pretty. =)
Our time frame is extremely tight, I have to present a rough code draft on
Monday, and I have no idea whether it is at all possible to access the
RS232 ports directly from Linux, without digging deep into kernel
programming (which I probably wouldn't manage in the time anyway). So:
- Is there a way to control those pins from user space, directly enough so
that we can get the data?
- Alternatively, is there a _simple_ way (e.g. an IC) to put between the
data line and the RS232 that implements a handshake so that I can use
termios and so on?
(Remember, the time frame is almost nonexistant.)
Thanks to all who enlighten me ;)
-- _ciao, Jens_______________________________ http://www.pinguin.conetix.deWindows NT indeed has very low Total Cost of Ownership. Trouble is, Microsoft _owns_ Windows NT. You just licensed it.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/