At 16:42 -0400 5/8/04, [EMAIL PROTECTED] wrote:
>My problems with doing 9-bit serial are _almost_ resolved, but the required parity
>switching between send and receive is on the hairy edge, timing wise, sometimes
>missing the first byte (the responding device's address). I have now gotten it to be
>about 98% reliable, but am looking to make it more like 99.99%.
This is insane. It should be set to be 100% reliable. Are you using any handshaking?
If so, toggle the handshaking to stop the device from transmitting until after you
set the parity?
1. Toggle handshaking to suspend device transmitting
2. Set parity for computer tranmission
3. Set parity for computer receiving
4. Toggle handshaking for device to resume transmitting
5. read response.
Alternatives:
I. Get a better device! different parity on receiving and sending is a sort of
bizarre concept.
II. Get NI to support 9 bit transmissions in VISA and do the parity in software
-Scott
--
Dr. Scott Hannahs, Head of User Research Instrumentation
http://sthmac.magnet.fsu.edu
National High Magnetic Field Laboratory, Florida State University
1800 E. Paul Dirac Dr., Tallahassee FL 32310, (850)644-0216/FAX 644-0534
"There are really only three types of computer users:
1. Those that use Macs.
2. Those that wished they used Macs.
3. Those that don't know any better."
