On Thu, 2009-02-26 at 06:14 -0500, Phil Schaffner wrote:
On Thu, 2009-02-26 at 10:17 +0000, Anne Wilson wrote:
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There is just one serial connector on the computer, so I set it to monitor /dev/ttyS0. Either that is wrong, or communication is failing. I've been told to try minicom to monitor it, but I'm not familiar with minicom (or any similar app), so again, I may be wrong in the way I'm trying to use that. I was told that unconnecting the device, then re-connecting it should give me a raft of output to the terminal - I saw nothing.
Could someone please give me idiot-level instructions on how to tell whether I'm connecting to the correct port, or whatever other information I need?
Anne,
Are you sure the cable is correct? I recall in the past having trouble with an APC UPS that required an oddball RS-232 serial cable before it would communicate. There were different variants available and only one would work. Posting details of the brand/model of UPS involved might get better help.
OTOH, if the manufacturer has any common sense, at worst they'll require a "standard" (NOT!) null-modem cable. At best, they'll have circuitry/software on-board that accepts either a straight-through or null and adapts itself.
Being an _old_ telecom guy from way back, I prefer what was called a symmetrical null modem fully configured. From memory (and therefore suspect)
Pin---->Pin 2 3 3 2 4 4 6 6 7 7 8 20 20 8
Some also do 5 to 5.
However, a 2-3 cross and DTR and DCD high is all that really is needed.
Google for RS-232 will get you a ton of stuff.
As to the OP original question, check BIOS settings and make sure your serial is enabled. Set it to COM 3 and IRQ 4 should work. This would equate to "0" in an *IX system.
Look in your /var/log/messages file. At boot, you should see the device recognized.
Also, Minicom is _easy_ to use and understand. Give it a try. Even the man pages are not difficult.
Phil
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HTH