@Ken, back in the old days of serial comms, we used to build break-out boxes to sometimes determine data flows etc. It seems you are trying to use a standard rs-232 cable, and most vendors use the parameters I wrote earlier about. Buy a RS232 DB9 plug or even get an old cable, using paper-pins or crocodile clips, test each pin for its value. Do not put a meter to measure the voltages, it will load and blow the processor in the hardware. Set the terminal program to 9600,8,N,1 then use PIN 5 as the ground reference and first determine the receive channel or pinout, which should be Pin2. Once you are able to see the data on bootup, then you can do the same for send pinout which should be PIN3. You may also have to chane the flow control to RTS/CTS, so play around with the pins. Here is a guide on the pinouts : http://pinouts.ru/SerialPorts/Serial9_pinout.shtml Be patient and it will work fine. Remember