Serial comms: Delay between Read & Write

[Tarun]

Hi,
I am experiencing trouble with my LabVIEW app running in winXP. My
app needs to receive a character/command from a polling device and
reply with a character string. The polling device will send out a
character/command every 100ms.

My problem is that the app cannot reply quick enough. The string sent
by my app overlaps the next character/command from the device, because
of the delay is about 34ms.

I am trying to replace an older, less friendly VC++ app, which does
the exact same thing when run on XP. (There is a 34ms delay.) But
when running on Win98 the delay is about 2ms. ??? I think it has to do
with API calls. Transition between Read and Write commands.

Is there a way to reduce this delay? It is important. My other option
is to put a faster comms interface between the device and my LabVIEW
app.

Any help would be appreciated.
Jerry.