Hello adam12,
Thanks for your post back. For the pinouts of the USB 6221 take a look at the link below. It is a .pdf document that shows the pinouts for all versions of the USB 6221.
NI 622x SpecificationsAs for the CB-50LP, it shows on the deminsions drawing that the pin assignments are labled on the connector block. So pin 1,2,49 and 50 should be indicated on the board its self and the numbers incroment accordingly. Below is the deminsions drawing for the CB-50LP.
Now nowing the pin assignments this will allow you to wire the signals accordingly to the USB-6221 from your Gray Hill 24 Channel I/O board. Please post back if you have any other questions.
Corby_B
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