USB-1024LS connections constantly reading high, even when connected to ground

[RLovely]

I recently purchased a USB-1024LS from DigiKey, and some of the digital inputs on port A do not appear to be working in DAQami.  I can see A:0 and A:4 changing the graph when connected to GND, but not any of the other connections on that port – they just appear to read high constantly.

 

Am I doing something wrong, or have I received a faulty unit?

Edited January 25, 2023 by Fausto
corrected model #

[Fausto]

If you have checked the wires are secured by the screw terminal, then you have a defective board.  Reach out to the vendor, DigiKey, for a replacement.

[Fausto]

Hello @RLovely.

All digital I/O terminals are pulled high to +5V via 47 KOhm resistors.  If nothing is connected to a terminal, then it will read high.  Do not select a digital input channel, in DAQami, if it will be left open.

https://www.mccdaq.com/pdfs/manuals/USB-1024LS.pdf

Regards,

Fausto

[RLovely]

Thanks for your reply.

The problem I'm facing is that if I connect a switch as shown on page 3-3 of the manual to port A:2, I cannot see it changing in DAQami when I toggle the switch, even if I only have that port enabled.  Port A:1 works fine.

[Fausto]

Hello @RLovely.

In your initial post, you mentioned that only channels PortA0 (pin 21) and PortA4 (pin 25) were working, but now PortA1 (pin 22) is also working.  Please check and/or replace your wires/switch and verify that the wires are secured in the screw terminal.

 

Regards,

Fausto

[RLovely]

Sorry, my bad - port A1 is NOT working - I forgot they started at zero.