Serial port trouble

[Kevin Decker]

I am using Progress V9.1C18, Procedure Editor, Win 2000.

I have written an application to ouput data to an Elton Orion tag printer. My application uses sample code submitted by Chris Schriber which used Kernel32.dll to output data to serial ports. This has worked without fail for Win 95 & 98, but fails when used with Win 2000. I have narrowed it down to Kernel32's GETCOMMSTATE. On Win 2000, GETCOMMSTATE is always returning a 0. I have researched this function on the MS web page, but found nothing helpful. I suspect the DCB Structure is different for Win 2000 than it is for Win 95.

I would appreciate any ideas which might help.

Thanks,
Kevin

 

[Gabor Topor]

Hi,

Have you tried GetLastError()? What was the result of it?

Regards,
Gabor

 

[Kevin Decker]

GetLastError is returning a value of 1 wich translates to Incorrect Function.

 

[Gabor Topor]

What is the definition of your DCB structure in Progress?

Regards,
Gabor

 

[Kevin Decker]

Gabor,

Upon calling GetCommState there is no structure, it is defined only as a Memptr with a Size of 29. The structure is then modified after calling GetCommState. The modified structure is then updated with SetCommState (see code below).

SET-SIZE(DCBStructurePointer) = 29.
RUN GetCommState (CommHandle,
INPUT-OUTPUT DCBStructurePointer,
OUTPUT nRC).

IF nRC <>0 THEN DO:
ASSIGN DCBStructure = GET-STRING(DCBStructurePointer,1).
PUT-LONG(DCBStructurePointer,5)=9600.
bit-flags=EXP(2,9) + EXP(2,10).
PUT-LONG(DCBStructurePointer,9)=bit-flags.
PUT-BYTE(DCBStructurePointer,19)=8.
PUT-BYTE(DCBStructurePointer,20)=0.
RUN SetCommState (CommHandle,
INPUT-OUTPUT DCBStructurePointer,
OUTPUT nRC).
IF nRC=0 THEN
MESSAGE
"error setting new parameters"
VIEW-AS ALERT-BOX.
END.



Thanks,
Kevin

 

[Gabor Topor]

Kevin,

I have the following questions:

1. Have you checked CommHandle before GetCommState() call?
Checking not null is not enough it can be INVALID_HANDLE_VALUE also (defined as -1).

2. Have you checked the event log?

Regards,
Gabor