I run LV5.1 under NT4, SP4 on a 350MHz Dell with 128MB RAM and 6GB hard disk. There is an NI PCIMIO 16E4 DAQ card in the system, as well.
Problem is that the serial port VI takes 100% of the CPU according to task manager and this does not seem right to me. Buffered I/O from the DAQ card is not possible concurrently with the serial port VI. One or the other will run, but not both. Asynchronous acquisition _will_ work with the serial VI.
Is this a fundamental problem with NT or do I need to reconfigure something? Based on past threads, I have looked at my system configuration and drivers. All seem to be correct and the most current version.
--- Ravi Narasimhan
-- Ravi Narasimhan Dept. of Physics and Astronomy, UCLA http://www.physics.ucla.edu/~oski
> Problem is that the serial port VI takes 100% of the CPU according to > task manager and this does not seem right to me. Buffered I/O from the > DAQ card is not possible concurrently with the serial port VI. One or > the other will run, but not both. Asynchronous acquisition _will_ work > with the serial VI.
I faced the same problem - even worse (trying to asynchronously work with two serial ports read/write). None of the stock VIs handle this correctly. My solution was a double loop - the inner loop uses "Bytes at Serial Port.vi" and "Wait (ms)" to poll the serial port in nonblocking fashion and avert the dreaded lockup, and the outer loop reads a character at a time and concatenates it to the shift registered result string, while checking for EOL. The result w orks beautifully, and should be able to support as many serial ports as you care to enable.