Dear everyone.
I have problem to using Labview Visa serial program , visa-read and visa-write.
I make my application with two deviecs having RS-232 port and one device having USB port.
Because I must read many bytes from RS-232 devices, so I program to separate writing and reading process of these devices for
other function. I use parallel loop design pattern.
My plan is below.
In main loop - I analyse , calculate and display data in graph pattern.
In event loop - I separate serial reading and writng with some interval for other event handling.
I write a command to the first RS-232 device and go to next step without waiting for reading data from RS-232 of that port.
In next step, I wirte a command to the second RS-232 device and go to next step without waiting for reading data from RS-232 of that port.
After writing command to two RS-232 devices, then I command to USB devices.
At last step I read data from the first RS-232 devices, next the second RS-232 device and USB device. In these step I only transfer data to
the inside buffers.
These processes are going in order.
When I tested visa-wirte and read together, it worked well.
But when I tested reading and writing process of RS-232 with time interval, but I couldn't.
After witing command to RS-232 port of the first device, wait for some times, then I read data from that port.
-I set serial port setting correctly.
Always I got message "VISA: (Hex 0xBFFF0015) Timeout expired before operation completed. ".
How can I solve this problem.
Thank you.