Hi Ralph,
Once the GUI is communicating with the EVM, there are two methods to set/reset DIR.
You can select the Motor Direction, Forward or Reverse button or you can click the DIR pin. Either will change the GPIO.
Image may be NSFW.
Clik here to view.
When either method is activated, the GUI will send a USB command to the FTDI device, which in turn sends a UART command to the MSP430 on the EVM.
Unfortunately, I do not know the USB command nor do I have access to the GUI source code.
One method to determine the code is to use a USB sniffer. Once captured, the USB traffic could be sorted through to determine the command.
Sorry I don't have the actual command available.
