On Mon, 2006-08-07 at 19:34 +0200, SoNicX wrote:
> hello,
> i have wired myself a nullmodemcable to connect a small machine to my
> centos-ltsp-and-so-on-server.
Garbage null-modem cables can cause problems, A reliable one has
something like
2 3
3 2
4
6 20
8
4
20 6
8
468 jumped together and go to 20 on the far side. This is a
"symmetrical" null modem cable and allows for hardware flow control and
detect power on, etc. I seem to remember 5 being int there somewhere, so
google and make a good null-modem.
The other part you need to do is mentioned below.
> using agetty i can login fine, just a few
> garbage chars here and there but working is ok. now this isnt what i wanted,
> so i disabled agetty, made a line in syslog.conf like
> *.* /dev/ttyS0
> and made the system produce a lockfile after syslog is started to lock that
> serial port. now data reaches my minicom using terminal emulator, but its
> garbage, looking like this:
> ...x.x.x at ..x.x.
> and so on. if i do
> echo "somechar" > /dev/ttyS0
> its the same garbage. im sure this is a quite simple thing, but i dont get it
> to work. do i need another terminal prog if i try to send plaintext with
> syslog (as it seems to me clueless as i am). do i need to manipulate syslog
> output somehow? i tried to fiddle around with setserial but the port should
> work, as they to with agetty. i hope someone on this list has experience with
> this, doenst seem to be too popular.
'man stty' might help too. The problem is you need to maintain a
consistent baud rate. Once the terminal line is opened and *held* open,
your baud rate, parity, line discipline, etc should remain. When line is
closed, it falls to some default, but can float.
Keep in mind that RS-232-C (?) specs ap[ply and there are limits as to
distance (un-amplified) and baud rate. I presume you are not trying for
2400?
Anyway, get the line open and run the stty against it and let the
process that opened it sleep forever with the line open.
> mfg
> sonicx
> <snip sig stuff>
HTH
--
Bill
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