What is the single channel adc sample rate for myrio?

[my_dubs]

The spec states 500kS/sec aggregate. I am unsure how to determine from that spec exactly how fast I can sample using only one ADC channel (AI0). I've searched the forums, but have not found exaclty what I was looking for. Thanks for your help.

[Roohcifer]

Hey my_dubs,

Since all AI is multiplexed on the myRIO, you can achieve a maximum sampling rate on any combination of AI channels of 500 kS/s.  In other words, if you're only using one channel, you can sample at 500 kS/s.  If you sample on two channels, you can get 250 kS/s/channel, etc.  Keep in mind that each channel of audio also counts as an AI channel.  For example, if you are using AI0 and the R and L channels of the audio input, you will only get 166 kS/s/channel.

The MUX configuration of the myRIO-1900 is available on p.8 of the spec sheet if you want to see what counts as an individual channel:  http://www.ni.com/pdf/manuals/376047a.pdf

Regards,

[Flaku]

I can achieve sigle channel 500 kS/s, but after adding second channel loop frequency decreased to 125 kHz. How can i achieve 250 kS/s on two channels?

I attach the FPGA vi.

Loop "A/AI0 Input N samples read" works perfectly when "Connector C/AI1" fragment is removed. It's duration is 80 ticks, that means 2 us, so 500 kS/s. But when i wanna measure this second channel analog signal and add this fragment, loop time is increasing to 320 ticks for loop. That is 4 times more, not two. Can anyone tell mi why is this loop so slow and how should i fix it?