Serial communication under NT


Thread Starter


I have a problem with serial communication using a PC under NT and a external controller. When sending data, by using the hardware control flow, the NT system still send some information even when the external system asks to wait. When using windows 98, the communication works fine, but we have to “play” with the advanced setting of the com port. (Transmit and receive buffer) Does someone know if these buffers can be set or controlled under NT??? we are making our own application writing under Visual Basic

kalpak dabir

If you are using the mscomm control of vb5.0 for serial comm, check it out first, it's somewhat buggy under win95/98, i dont know about NT. Also check your cable, the 9 and 25 pin d connectors have some signals interchanged, and that also depends who is DCE or DTE.

Robert Willis

What is the application that you are running under Microsoft Windows NT? What is the protocol that you are attemting to run on the RS232 port? Typically the problem you describe is caused by a "older" application that was not specifically written to support the NT enviroment. Regards Robert Willis

Pedro Miguel Carrión Salomé

I use VB 6.0 with the MSCOMM with windows NT 4.0 (Service Pack 4) and it works fine, you can set the buffer and control . You have to do a routine(Using communication event) that you can find in the Microsoft Site, i recommend use the communication event in order to get a reliable communication with your device. Regards, Pedro M. Carrión