02-02-2021 07:06 AM
Hi,
I need to get 16 DO generated with 2 analog outputs AO0 & AO1 on ELVIS II board.
My need is changeable values of these signals. As amplitude, frequency.
To achieve this I tried my VI code, which gets me following error:
My code with error is named: My_example_gen.vi
Example code from help is named: example_gen.vi
200621: Onboard device memory underflow. Because of system and/or bus-bandwidth limitations, the driver could not write data to the device fast enough to keep up with the device output rate.
Reduce your sample rate. If your data transfer method is interrupts, try using DMA or USB Bulk. You can also reduce the number of programs your computer is executing concurrently.
-I think its related to bus buffer. Is that true?
After this error I go to Help examples and implement digital part from my code to - Help > HW In & Out > DAQmx > Analog Output > Voltage - Continuous Output .vi.
After run it I got error 200621(5-6x times). But sometimes, I dont and it goes without error, even if I stop the loop. I dont get any error. Sometimes = every 5-6x click on Run button.
The main difference is (if I dont mention errors which I like to avoid) I dont get from:
-My_example_gen any analog output signal, only signals from digital output.
-On the other side I get in VI example_code two analog output signals alongside with digital outputs.
Is there any clue?
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Thank you!
Both VIs are included.
Solved! Go to Solution.
02-02-2021 07:27 AM
Hello,
I found myself solution. Im not sure if its right, but its working now. Hope it someone helps. Thanks 🙂
02-03-2021 02:05 AM
Today I sadly found out, this solution only keeps better. It gets the same error 1 time from 10 random run.
I keep working on solution about the memory. If anyone knows something about it, please share it.
I found out following:
NI ELVIS II supports
for AO:
On Demand Analog output
Finite Analog output
Continuous Analog output
Continuous non-regeneration Analog output
for DO:
SW-Timed Digital output
DMA FIFO - Direct Memory Access First In First Out
Seems to be unsupported (supported only for NI RIO devices , NI Academic RIO devices & Elvis III)
-Cuprum