I have a machine with an A-BIT SM-5

[dix33]

I have a machine with an A-BIT SM-5 motherboard with a PCCOM 4 port ISA serial card running windows 95. problem is that the 4-port serial card appears to install OK but will not parse data.
Com 1 & 2 are fine. The serial card is fully functional having been checked on another machine of similar ilk. The diagnostic provided for the card carries out a TX-RX check that works on the other machine but stalls on the SM-5 machine.

I would really like to know if the SM-5 mothercard has some issue with 4-port cards that needs some special setting to work. I have run out of ideas as have guys with more knowledge about this than me.

 

[dkdude]

Check to see if the IRQs that the ports use are the same as on the other PC -AND check to see if there are conflicting IRQs...

In general COM1 and COM3 share the same IRQ (not a problem) and COM2 and COM4 share the same IRQ (still not a problem). However, other devices may use one of those IRQs -in that case, try to re-assign or reset resource assignment (this, however, CAN cause additional problems, so be carefull).

Good luck §;O)


Jakob

 

[dix33]

dkdude

Thanx for the info. I do not have an interrupt problem. I allocated 5 which was unused on this machine and showed no conflict in device manager after setting it. The resource assignments do not appear to conflict with anything either. Very strange, which is why I think it could be a mobo specific issue.

Regards

Dick C

 

[dkdude]

dix33,

Mind you .... you cannot assign just any unused IRQ to your RS232 port adaptor unless it actually CAN use that IRQ!

Old adaptors is hardwired or configured with jumpers or DIP switches.

Is the adaptor PnP? If it is, then it should automatically grab a vacant IRQ -if not, refer to the manual the adaptor came with, or look at the settings it had on the other PC, where it worked.

Good Luck §;O)


Jakob

 

[SYAR2003]

Get a pnp aware PCI card ( cost about 15-UK£ / 25-US$ ).
Throw away ISA .
I will guess measuring the time spendt on troubleshooting OS with this ISA card would finance a new PCI card.

 

[dix33]

DKDUDE and SYAR2003 thank you both for your comments. SYAR2003 your comment is absolutely correct but this is not now the issue. The issue is that some stupid "little" thing is ballsing up what should be a simple procedure, and I now need to know what it is (plus a load of others who are not prepared to expend more time on it). Is it finger trouble or a real bug?

DKDUDE - the card in question is the PC COM ISA 4-port serial card. The website is excellent, provides drivers for all OSs and diagnostics and install info but no info on this problem. I did some more work today, it gets more interesting....

Regarding interrupts the card uses INT 5 as default. The card is not P&P and the mothercard setup forces that interrupt for legacy ISA use. I had a working card in a pentium 133 machine which required a win95 re-install on account of its previous user really wrecking the OS with crapware. He had everything...

What I noticed was that the card was adding com3 to com6 and thay all worked. Checked settings which were as the makers manual...OK. Checked out other cards on this machine to check they all worked...OK.

When I formatted the HD and reinstalled Win95 this machine which was working perfectly with 6 com ports, now exhibits the same problem as I have with the other machine! COM 1 & 2 OK no operational com3-com6.

The re-installing of Win95 has caused the problem...so now, if I fix one I guess I fix the other. The card maker offers no registry tweaks for this card, it is a dumb card so shouldn't need much.

I also have two more machines with win95 and win95B running respectively and their 4-port cards work fine...

Its pretty clear to me that windows needs a tweak but what?

 

[SYAR2003]

Make sure the i/o addresses and mem adresses the card uses
are free in windows ,as well as the interrupt .


MSD.EXE will work on a Windows 95 machine but is not normally installed as part of the normal Windows 95 installation. You can find it on the Windows 95 CD however and then copy it to the C:\WINDOWS\COMMAND directory to make it work.


MSD.EXE can give incorrect information when run from within Windows.if that is the case shut down to DOS mode before running it ("Restart the computer in MS-DOS mode&quot