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pthurman

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serial port detection

Can't detect devices on  seial ports on a pt-2003 MB. p166 processor installed. tried 3 different sets of ram, 4 different mice, 4 cables, tried dos 6.22 with good mouse drivers, and win95 setup. Tried every combination of bios (don't have type or version handy) settings. systematically tried both on- board ports.
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Mrbreeze

PT,
With Win95 does Device Manager show conflicts? You said you tried BIOS settings so I assume the ports are showing enabled there. Some old boards have cable connection to the motherboard instead of being built in. Also some old boards have a jumper or dip switch to disable the port. Just some ideas
                      Mrbreeze
In Device Manager is the ports listed there?
What devices do you have attached to the serial port?
Are you using an adapter to hook (it) up?
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I haven't loaded win95, win95 setup doesn't find mouse.

mouse isn't detected in dos 6.22, hard drive is one
I use for testing... it's mouse drivers are the best i've found.
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RoadWarrior

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I've tried multiple cables...these are on board standard 8 pin comm ports.
8 pin serial port???   No such animal exists that I know of.
Most serial ports are 9 pin or 25 pin.  
Maybe this is your problem, if yours only has 8 pins (1 broken off) then maybe it is missing an important one and that is the reason it is not working.

Are you using a regular serial mouse or are you using an adapter to a combo mouse?   In case you didn't know this, you CANNOT use an adapter to hook a PS2 mouse to the serial port, it will not work, only a combo mouse with the PS2 connector will work (there should be a switch on the bottom too if it is a combo mouse)
Sorry maybe I misunderstood your 8 pin comment, Are you talking about the MB hookup for the serial port and not the serial port itself?
correct, standard comm  hookups on MB. Used combo mouse and serial mouse... 2 of each I think.
Is there a reason you don't use a PS2 mouse? That MB should have the hookup for a PS2 connector (I don't know that but will try to find out for sure)  Are you wanting to get the serial ports working in order to add something else?

Do you have two serial ports or just the one? If two did you try the other one, you can get an adapter for 25 pin to 9 pin for a few dollars

Just trying to see if there are any more options?
rayt

I have the board laying on a static bag to check it.
No mater which cable I hook to the comm ports on the board, it will not detect a mouse.
What about a hookup for a PS2 mouse?
Who makes the MB?
intel chipsets
no ps2.
Ouch
Hmmm
Are the ports seen by any dos diagnostics like MSD, Norton Sysinfo or Diagnostics, or Snooper etc? If you have Norton Diagnostics do they pass the internal loopback tests etc?

I have had a couple of Opti chipset based boards that have had serial port failures, they wouldn't even use a port on an i/o card when the onboard ports were disabled :-( hope this is not your case.
Will try msd.
will also flash the bios.
thanks
Wow,

Tied another set of serial cables (about the 7th set I tried). that I pulled out of a empty case in the corner and viola!

thanks to all that helped.

500 pts to the one who can tell me why and how these cables differ... how to tell them apart, and if you can tell in advance which motherboards will need which type?

Roadwarrior was obviously correct on the differing cables and should get the original pts.

If an acceptable explaination is provided I'll post and award pts.

Thanks again,
Pat
Thanks Pat.

Here is the wiring of 2 of the types. (most common)
 with a flat cable numbered 1234.......
 at the 9 pin D connector
some go
1 2 3 4 5
  6 7 8 9
and  some go:
1 3 5 7 9
 2 4 6 8
and the other type I saw once I didn't even bother figuring out, I think it was trying to keep signal pairs together and had an extra ground in.

There appears to be no rhyme or reason why one or the other type is used, I have seen both in the same model line from the same manufacturer. Perhaps there is a particular i/o chipset or make of UART that favours one arrangement over the other for easy board design.

You can probably only tell in advance if there is a pinout of the connector in the motherboard manual and match the below assignments given..

9pin  25pin  assignment
1       8       DCD (Data Carrier Detect)
2       3       RX  (Receive Data)
3       2       TX  (Transmit Data)
4       20     DTR (Data Terminal Ready)
5       7       GND (Signal Ground)
6       6       DSR (Data Set Ready)
7       4       RTS (Request To Send)
8       5       CTS (Clear To Send)
9       22      RI  (Ring Indicator)

so if the pinout in the manual is given as 1=DCD 2=RX then it is the first type of connector, if it is given as 1=DCD 2=DSR it is the second type.

Visually you can tell the cables apart since the first type will have the wires split up/down alternately to connect to the socket whereas the second type will have the ribbon split in about the middle with the first half going to the top and the second half going to the bottom. If the connections have a big glob of plastic over them then if you see no splits it is probably the first type wheras the second type will give an obvious split and kink in the cable.

regards,

Road Warrior
*grin* I just had a laugh at my own stupidity, I picked up the nearest mobo manual I had to see if the com port header pinouts were given, and flicked back and forward a few minutes before it dawned on me it was the manual for an ATX format board, ports already soldered to it! :-)
will post a question for you same catagory.

Thanks much,
Pat