G120 Analog Inputs with USB debug

I have a custom G120 board that is reading a thermocouple board via 2 analog inputs on analog 0 and analog 1.

I noticed something strange since I switched to VS2013 and the latest SDK (not the beta). This was not happening with VS2012 Express.

If I have the USB debug connected when it boots up, the analog readings are all messed up for channel 1. Channel 0 which is the room temperature for the thermocouple and this is fine but analog 1 for the thermocouple itself is not.

With the USB disconnected the system boots fine and the readings work.

If I boot up with the USB disconnected and once running, connect it, the readings remain fine. Starting an app to debug is also fine.

This is 100% repeatable. Every time I boot with the debug plugged into the PC, it will give an incorrect reading on analog 1. Plug it in after and it works perfectly.

@ Dave McLaughlin - Just to be sure, can you post a small program that shows the issue?

Hi John, I’ll see if I can write something up for this.