I checked the cables and power supplies. They look good. I downloaded the latest Phidget Control Panel and updated the firmware on all of the modules.
I now get a slightly different response. Soon after I start the stepper (continuous mode) I get a "Timeout Error". The stepper continues to move and can not be stopped. (more timeout errors). The other modules (relay, encoder, temp sensor, LCD and 2 hubs) do not appear to be affected and continue working. Unplugging the communication cable from the stepper has no effect. Unplugging the USB cable has no effect. The only way to stop the stepper is to remove the power. Any ideas?
Thanks for the help