serial not work on my 486 machine

Hi all,

  My machine is 486(AT). I have problem with serial port not work! I try to replace I/O Controller but not help me to fix my problem.

  I try to check serial configuration in BIOS but nothing to set about serial.

  Harddisk and floppy disk was work fine.

Anyidea?
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kawinAsked:
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dbruntonCommented:
Generally you have two serial ports on your machine.  Try using the other serial port.

One serial port is a 9 pin male plug, the other a 25 pin male plug.  If these two plugs have cabling that  come from the motherboard to the case you should be able to swap the cables other so that the 9 pin plug is now on the serial port.

If however your serial ports are on the IO card then you need to buy a new IO card.

For a better diagnosis you need to specify the motherboard, where the ports are - card or motherboard, the operating system being used and what you need the serial port for.
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kawinAuthor Commented:
I try that on all controller that I replace!.

That machine use dos 6.22 + windows 3.11.
Bios is AMI.
I don't know about mainboard and I/O (Noname I think it from TAIWAN or Chaina)

Mouse is msmouse compatible (I tested with other machine and it work fine).

Any suggestion?
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BigMarkCommented:
Drop out of windows back to DOS and run msn {enter}.

Have a look at the sections regarding interupts and serial ports.

One of the serial ports may be disabled on the card, or you may have another device using the interupt for that port.

Standard settings are:

Com1:  3F8 - IRQ 4
Com2:  2F8 - IRQ 3
Com3:  3E8 - IRQ 4
Com4:  2E8 - IRQ 3

Note:  IF you have an internal modem in the PC make sure it is not sharing resources with Com1: or Com2:.

Get all of this right and you should have a working system.



BigMark

P.S.  You could try an external loopback test of the ports if you have access to a diag program.......
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ga9ulCommented:
If you don't have a diagnostic program to test your serial ports, you could try using debug to check them out. Debug should be in your DOS directory. If you need instructions on how to use debug please comment.
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MortenLCommented:
If nothing else works, this error can be caused by an error in the powersupply. Sometimes -12V is missing due to a burned regulator, and this error is very seldom discovered, since ontly serial-adapters uses this voltage.
The voltage can be measured on the power-connector to the mainboard - BUT take care. You can seriosly damage yourself and PC by e.g a shortcircuit.
Alternatively lend a serial-port tester from some hardware shop...
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ga9ulCommented:
Morteni, you should know better, if 12volts is missing the hard drive won't work!
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OttaCommented:
> run 'msn'.

Also, try running 'MSD'.  :-)
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kawinAuthor Commented:
My machine not have modem. It have sound card (sound blaster compatible)

I alrady remove that sound card from my system while test

Anyone can suggest me about testing serial port I need more information. (How to do test? Which tool I need for test? etc.)
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OttaCommented:
The easiest way to test COM1 is to disconnect the PS/2 mouse, and connect a serial-port mouse to COM1, and boot in Windows, and see if moving the mouse moves the on-screen pointer.
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RoadWarriorCommented:
ga9ul

MortenL said -12v, not +12v and in modern PCs the serial port is about the only thing that uses this. A good thing to check.


When you change the i/o card, make sure the com port headers are the right type for the new card, there are several types, unless you are replacing the card with exactly the same model, the odds are against the cables from one card working with another by 3-1 or so.

Have you ever had the serial ports working? if you have not, maybe the card you had in had the wrong cables too. (some discount vendors just bundle whatever cables they have with whatever cards they have.....)

Any diagnostic program usually gives basic serial port info, you need loopback plugs made to be able to tell much more than that, here are a few, Amidiags, Norton Diagnostics, Snooper, they will tell you if the UART is working and to what addresses and IRQs the system thinks they are set, if all seems okay in any of these, but you can't get anything to work, then it is a cabling problem.

regards,

Road Warrior
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dbruntonCommented:
You have dos 6.22 so drop out of Windows and type msd

This utility or test program will show you your machines configuration and it will tell you what serial ports that you have.

Please find this information and report back to us.

If msd doesn't run then type

cd \
cd dos
msd

This should find msd for you.  This is Otta's suggestion.
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RoadWarriorCommented:
I mistrust MSD especially where com ports are concerned, I had a system where it was reporting the presence of com 1 and com 2 after they were disabled, another where it couldn't see 3 and 4, but they worked fine, also it can't tell some clone 16550 A's from 8250 Uarts, some 8250s it calls 16450s etc etc. and in general I found it doesn't give any hint as to whether anything is really working or not. On about 75% of working systems it reports everything as it should be however.

It's plus side is that it is on a lot of dos 6.xx installations when you forgot your favourite tools disk.

I prefer Snooper as a quick and easy diag tool, it's shareware, get a fully working trial version here (Nagware) ...
http://www.simtel.net/pub/simtelnet/msdos/sysinfo/snoop342.zip
runs on everything from 8088, 286, 386 etc  to sixth gen, runs when msd locks up, runs when norton diags or sysinfo locks up, doesn't fight with memory managers, grinds, cuts, grates, slices, dices and peels, dang no that's the supa-mecha-cuisinatron 3000.

well that's probl'y just my opinion, but if MSD doesn't tell you much, or tells you something you don't like, you may as well give snooper a shot.

regards,

Road Warrior
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jjmcdCommented:
kawin - was the port working once?  With the same wiring?

Serial port wiring can be a pretty picky thing, especially on Dos/Win3.x and especially with some software.  Nine times out of ten the problem is in the serial port wiring rather than the port itself.

I think you said that the port is on an I/O controller card, which means that no serial port BIOS settings is to be expected.

The good news is that new I/O cards are pretty cheap.

The bad news is that most of those cards have lots of jumpers and the settings are dependent on the particular board.

*BUT* if you see your port in MSD then you at least know the jumpers are set close enough to recognize it as a serial port.  If it's not the default IRQ and address, tho, a lot of programs won't recognize it.

How do you know that your serial port isn't working?  Are you using a particular program or device?  Have you tried it with other programs and/or at least looked with a voltmeter or breakout box to see if anything is happening?
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ga9ulCommented:
Kawin, you haven't responded as to wether you have tried debug or not. Debug is a no nonsense direct way to check out a serial port. All you need to do is connect pin 2 and pin 3 together on your serial port socket and then run debug from ms-dos prompt. Just type debug and a - appears in place of the normal c:> prompt, then type:- o 2f8 3a <enter> and then type i 2f8 <enter> the next line that comes up should be 3A (thats if your testing com2, for com1 just type 3f8 instead of 2f8) when you've checked your ports just type q <enter> at the - prompt to quit the debug program and return to dos.By the way the o above stands for output don't use the zero (0) key!
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kawinAuthor Commented:
Hi all, Sorry for respond too late.

Here out put of MSD,

               COM1  COM2
Port            3F8     2F8
Baud rate 2400  2400
Parity       NONE NONE
Databit           8        8
Stopbit           1        1
CD                NO     NO
RI                 NO     NO
DSR            YES      NO
CTS              NO     NO
UART          8250  8250

Current I plug mouse to com1. After I change mouse to com2 DSR at com2 is say YES.

Ok, I will try to check my serial functioning by using cross cable. After I check I will post result here.

Thank all.

otta:
   my windows is dos6.22 + win3.11. My mouse driver have program to test mouse in dos mode and my mouse is not work. In windows it not work too.


   
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RoadWarriorCommented:
Just wondering, do you have a real serial mouse or are you trying to use a PS/2 mouse adapter on the serial port? also have you tried a different mouse?
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dbruntonCommented:
Can you set your mouse testing program to check for mouse at COM2 when your mouse is plugged into COM2?
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kawinAuthor Commented:
RoadWarrior:

    My mouse is serial mouse, I test with other machine and it work fine. I also test change mouse too but it still not work.

dbrunton:
    When I plug my mouse in com2 I told mouse driver to use mouse at com2. But it still notwrok.

    I have 3 version of mouse driver! One is microsoft (bundle with dos, I think). Other is mouse (samename) and mmouse. (I don't know what difference of that).
    For mouse and mmouse.exe it have tool for test mouse. Normally when I test mouse I use that tool to test mouse.

   Mouse driver from microsoft was only say can't not find mouse on comX. Every time I check. But other mouse driver was say mouse at comX, irqY, port ZZZ.

   Anyone think about problem with mouse driver? Any suggestion?

Thank.

Note: My mouse is genius and microsoft clone mouse.
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Alisher_NCommented:
check if you have a small switch on mouse named MS<->PC, if you have it it must be in MS state, contact problem with this switch also could be problem.
also try several other mice on your computer, if system will find them...
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RoadWarriorCommented:
MS puts the mouse in microsoft mouse mode, which is how it will work with the microsoft mouse driver, PC puts the mouse in mouse systems mode (otherwise hold down a middle button if you have it on boot and have no switch) and should work with the mmouse driver. MS mode should also work with the mmouse driver. BUT if the mmouse driver loads in mouse systems mode whether or not you have the switch set or hold a button, it usually means it didn't find a mouse.
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dbruntonCommented:
But other mouse driver was say mouse at comX, irqY, port ZZZ.

The above statement.  Does this give the statement whether a mouse is plugged into the COM port or not?

Or

Which of the following is true and which is false.

It gives the statement with a mouse.
It gives the statement with no mouse.
It does not give the statement with a mouse.
It does not give the statement with no mouse.
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kawinAuthor Commented:
Sorry for slow response,

Now I test attach external modem to my serial port.

I see LED on RD,SD,TR and CS is ON and CD, OH is off when I power on my machine.

Try with both serial port. It same.

I use Telix to connect to my modem and it still not work too.

I will claim my I/O card (replace with new one) I will post result after I change I/O card.

Any Suggestion?
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kawinAuthor Commented:
This question has a deletion request Pending
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ga9ulCommented:
This question no longer is pending deletion
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ga9ulCommented:
Before deleting this question, could you tell us all if replacing the serial card solved your problem? If it did you may want to award points to whoever you think helped you the most. This will make people more interested in answering any quetions you may have in the future. I delete questions only when I have had no helpful suggestions or no response at all.
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ga9ulCommented:
Additional comment before pending deletion:- mortonL>>> Sorry about the -12v comment, it was just the way it displayed (looked like hyphen and not minus sign ie  -     12v  not -12v)
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kawinAuthor Commented:
I replace I/O with new one but not help, I tested new card on other machine and it work fine. I think this is mainboard problem.  I will looking for new mainboard to test.

think only way that I can diag my problem is replace one by one until I found the cause of my problem. Yes, it not need expert to do this. (but I might help me to solve my problem)
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ga9ulCommented:
You still didn't tell me wether you have tried using Debug (see earlier comments). Also can you check your motherboard for -12v? Get someone with a multimeter to test this for you. Like you say, it does sound like the motherboard has failed.I would award points to MortonL or Roadwarrior.
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kawinAuthor Commented:
Adjusted points to 150
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kawinAuthor Commented:
I got new mainboard to replace today. Tomorrow may I can post the result.

I don't have tool to make loopback test. But I checked my I/O card already.

What the main point of check 12V? If my 12V was missing (to mainboard?) my machine should not boot up. But, I don't sure because I'm not good in electrical, if you mean ground is not 0V? What should I do? replace power support? or mainboard?

Thank.
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ga9ulCommented:
I meant the minus 12v (-12v) if you read MortonL's comment from 4th February, he asked you if minus 12v was present. If you can't read the voltage yourself or get someone else to, try to swap out your power supply before changing your system board, maybe you could borrow a friends? Take care if the power supply has a switch on a lead. Try not to disconnect the lead from the switch, you should be able to unscrew the switch from the computer case without disconnecting the lead. Also make sure you have unplugged your power supply from the wall socket before attempting to unscrew the power switch from the case.
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kawinAuthor Commented:
I change my mainboard and my serial port was work. MY PROBLEM WAS SOLVED.



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kawinAuthor Commented:
This question has a deletion request Pending
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kawinAuthor Commented:
MY PROBLEM WAS SOLVED. I change mainboard and my serial was work it so easy? I don't know why!
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ga9ulCommented:
This question no longer is pending deletion
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ga9ulCommented:
Don't wish to be rude, but don't I get points for that? I did say one option was your system board (amongst others).The only reason I can see for you not awarding me points is that you didn't know that the Main Board IS the System Board. Sorry if I didn't make that clear, but ask any expert and they will tell you that is true. Anyway, I'm happy to see your problem has been solved.
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ga9ulCommented:
Sorry about that last comment. Having re-read all comments again I suggest you award points to MortonL or Roadwarrior, they helped you the most. After all the effort they put in to solve your problem It would be unkind not to award points. Again let me say that I'm not trying to offend I just think you should follow the protocol.
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kawinAuthor Commented:
I give this point to you because your tried.
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