No Response from Some Port Pins, USB-1024HLS

[Simple Minded Engineer]

I'm using an USB-1024HLS and it's not acting correctly.

I have written a starter application in VB.NET. When I write 255 to Port C all of the outputs are set. When I write to Port A pins 0, 3, and 5 are low. When I write to Port B pins 0, 1, 2, 5, 6, and 7 are all low. I can set or clear the bits individually and the result is the same. I believe I have a bad device. It was just purchased and this is the first time I powered it up.

I have repeated the behavior using the ULDO01.vb program.

[JRys]

Configure the device to use the pull-up resistors to ensure they go high. See page 3-5 of the user manual.

[Simple Minded Engineer]

I get the same response on Port A, pins 0, 3, and 5 all stay low.

[JRys]

How are you testing to see if the pins are high? If it's with a voltmeter and you are touching the probes to the screw terminals, then your test method may be the problem. So that you know, the screws make a good connection only when they are anchored onto a wire or screwed down tight. When they are left unconnected and floating, the connections are intermittent.