thanks for the great info. i just solded (?) 2-3 3-2 5-5 G-G and it works now even on 115kbps, as there are some lines left iin the cabel ill try that 4 6 20 8 to, for some more luxus. rs232ports are such a nice feature. my server board supports remote access so its even nicer. but i still have to switch speeds that way, i guess minicom will eat some script to change speed to 115k after boot. thanks again. sonicx
On Monday 07 August 2006 20:13, William L. Maltby wrote:
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 8468 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@..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