On Thursday 26 February 2009 13:37, William L. Maltby wrote:
Look in your /var/log/messages file. At boot, you should see the device recognized.
Feb 26 12:12:25 borg2 kernel: serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A Feb 26 12:12:25 borg2 kernel: serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
Didn't you say there was only one port? There might be a second on the main board that is accessible via a header. If it's not hooked up disable all but the first in the BIOS (later). It's not really hurting anything as is, but it will free the I/O address and IRQ for assignment to other devices.
I believe you are right. I remember those - and the 25-9-pin adapter :-). Peering around the back in a dark corner, I could well have been mistaken. OK - female socket, so that's a COM port, I think.
Now I'm really confused. The BIOS definitely only shows one COM port. To be honest, I can't remember whether I connected it or not. I guess I ought to open the box and see what's what, but not today - it's already too late to do that.
But wait until you have things working - I suspect you have _two_ ports (probably 1 9 pin and 1 25 pin). A second port of 25 pins might easily be mistaken for a printer port. Long ago a switch from Centronics style to RS-232 style began to become the "standard". Physically, it looks the same as a serial port, the visual difference being the "gender" of the connector will be opposite.
Feb 26 12:12:25 borg2 kernel: 00:05: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
Is this what I'm looking for? I don't see anything else.
Yes. That means that all is as expected (i.e. as _I_ expect).
Also, Minicom is _easy_ to use and understand. Give it a try. Even the man pages are not difficult.
Easy when you know how, eh? :-) I did try it. I changed it to monitor /dev/ttyS0. Apart from that, I hadn't a clue what to do. I did look at the man page, too, but not knowing what I was looking for didn't help.
I haven't used it for a _long_ time, but IIRC there is an interactive menu system that works with some keystroke, maybe <ESC> key.
Ctrl-A Z - yes, I found that.
Look for that stuff in the man pages and it should be clear sailing.
First, have you set the baud rate correctly? A lot of things used to default to 9600, but 38400 became common later on. Do the docs for the unit specify? If so, use the stty command, or in minicom or other terminal emulator it's method, to set the baud rate to that needed. Usually these days, no parity check is done so 8 bit characters should be OK.
Now, since the port is recognized the failure has to be from the port onward. If the RS-232 9 or 25 pin shell is connected via a cable to the main board, make sure that the cable connector is connected to the right header on the main board. Since Linux reported two ports, there should be two headers on the main board (_if_ that's the method - some ma inboards have them mounted directly on the main board). If the header/connector is not keyed, it may be connected backwards. If you have two RS-232D shells (9 or 25 pin) you may be connecting your cable to the wrong one.
I'll check all that out tomorrow. I only have a supplied cable for 9 pin, so if everything else checks out I'll just have to try changing settings to ttyS1 and see if that helps.
Moving on, have you been able to verify the cable is good? If you have an RS-232 patch device with LED's, you can see activity (DTR, DCD, etc.) by hooking the cable to it. If you don't have one of those, a digital multi-meter can be used to see if you have expected voltages on certain pins (+/- 12 volts, IIRC). If you don't have one of those, a plain old dumb terminal can be hooked up and settings changed in a trial and error method.
I'm not handy with a multimeter, but if I have to, I'll give it a try :-)
Since they supplied the cable, is it new enough to assume that it is not damaged? If so, I suspect something easy like baud rate.
Brand new. I know anything's possible, but I'd put a bad cable very low on the list of likelihoods.
Settings at present:
A Serial Device : /dev/ttyS0 B Lockfile Location : /var/lock C Callin Program : D Callout Program : E Bps/Par/Bits : 38400 8N1 F Hardware Flow Control : Yes G Software Flow Control : No
All this is as set up in nut. Liebert do supply 'Multilink' software, but in theory nut installs the latest Liebert Multilink drivers. I'm seriously wondering whether I should remove nut and install the supplied software. However, I realise that I need to check the hardware situation first. Hopefully that will be done tomorrow.
Anne