Is the ACK a multiple-character acknowledge? I had a situtation where the computer was too "fast" on receiving serial data. The event fired on receiving the first character and the program would empty the buffer before the serial connection had completed. This would lead to a partial read of data, took a while to find as it will not always beat the data to the buffer. I had to put a small delay between the event firing and getting the data.

>Hi all,
>Ihave implemented a routine that establish and mantains communication with an Electronic cash register, according with its proprietary protocol, via RS232 using MSCOMM32.OCX, VFP 6 SP3, using events. I take a chunk of data from a table, send it, wait for an ACK and continue. It does a fair work, communicates well in some circunstances, in certain PCs and not in others. The problem arises in a non repetible pattern, presumably failing to receive the ACK after a number of succesful cycles.
>I suspect that Windows or Fox does some 'invisible' work after a while without user interaction. I have disabled energy saving at Bios level and OS ( Win 98 2nd edition mostly)
>Can anyone give me a clue? Thank you in advance.
>Ernest Luque