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Comm ports not recognised

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modalman

Programmer
Feb 14, 2001
156
GB
Hi. I have just replaced my motherboard with an A15VG+. It all seems to work ok except comm1 and comm2 do not appear in the system>device manager. Also the ps2 socket is not being recognised. So I have no mouse and my external modem is not picked up. The parallel port works ok and so does the floppy which I understand is also controlled by an IO chip along with all of the above. Does anyone know if this is a motherboard fault or if it is all down to BIOS settings etc? Many thanks in advance. ASCII silly question, get a silly ANSI
 
If you're still having problems as of this belated response, here are some suggestions.

In Windows, go to Start > Settings > Control Panel. Double-click the "Add New Hardware" icon. Allow Windows to search for new hardware by itself. Chances are, it will find the ports and add them for you.

If it doesn't find them, go into CMOS. You did not specify what BIOS you have, but it will usually tell you which key(s) to press when it first starts booting up. You should be able to find something in there to the effect of peripheral configuration, where you can see whether the ports have been enabled or disabled. Of course, you want them enabled.

If they show enabled, you can next see if I/O addresses have been assigned to the serial (COM) ports by booting into DOS mode. (You can do that two ways: [1] hitting the <F8> key just as you hear the beep when it is booting up or [2] choosing &quot;Shut Down&quot; in Windows then &quot;Restart in MS-DOS mode.&quot;) Once in DOS, type

C:\WINDOWS\COMMAND\debug

You will see nothing but a hyphen, but this is as it should be. This is when you will type

D 40:00 09

If the serial ports are present, you will likely see a line that looks something like this (but not necessarily exactly, depending on how many ports it recognizes--up to four):

0040:0000 F8 03 F8 02 00 00 00 00-78 03

If there are no serial ports, it will look like this:

0040:0000 00 00 00 00 00 00 00 00-78 03

To get out of the Debug program, by the way, press the <Q> key, then <ENTER>.

If you still get nothing, you may have a bad controller. In this case (assuming it is an onboard controller, as most are now), you may get buy by purchasing a UART card and connect your serial ports to that (about $40 downtown). If you have to do this, you may also have to get an adapter to convert your mouse from PS2 to serial--it's just a little gizmo you attach at the end of the cable so you can hook it to either COM1 or COM2, in which case Windows should immediately recognize it as a serial mouse and assign a driver to it. The only problem here is, of course, that the mouse will tie up one of the serial ports.

If you were still having problems as of this posting and this has helped--or if it hasn't--let me know.

Have a good holiday
 
Many thanks Topscribe for your help. I eventually manually set the comm port addresses in CMOS. One of them was set to auto which seemed to not work. Windows then picked up the comm ports. After working out that I had a dodgy comm to connector ribbon things started working. The ps2 is still not working tho. I havent the right connector for this but at least I have a serial mouse now.
Thanks once again.
ASCII silly question, get a silly ANSI
 
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