We have an appication that uses subroutines V123, V124 and TSR COMMDRV.IBM to handle serial port communications. This application has ran four years on a 386DX-33 class computer. When this appication was moved to a 486DX-33 class computer hardware serial port timing problems manifested themselves. A software vendor who has worked with this application had told us in advance that this problem would manifest itself of faster computers.

Is there a patch, upgrade or work for this problem?

It was a long time ago now, but I seem to recall having to put a delay loop after (eg FOR X=1 TO N; NEXT N) after the V124 read. I think it needed about 50 milliseconds. I will see if I can remember client and find the code.

COMMDRV.IBM has timing loops imbedded in the code. There

has been no patch for this problem to my knowledge. As the

code was originally released for 8250 UART chips (serial port)

and not 16550 chips (current), you might try:

(a) using a DOS MODE statement to slow things down at the port.

(b) switching the motherboard to a lower speed, or software

switching the TURBO to low speed if this is possible.

© matching the speed of the PC's at both ends a little more.

(d) introducing configurable timing loops in the code.

Steve

stsm@ozemail.com.au

I eventually had to write V123 and V124 replacement routines using strictly AREV itself.

What method did you use to Communicate without v124?

I have the same problem with Win95.

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