Good, you're recieving the 20 character string. But, usually with each button press there are 2 strings, one that starts with PU8904..... followed by another string PU8905.... Did you not see a PU8904... string? Also for the link activate command the 14th and 15th characters should be a '2' and '0'. Your strings have goto command '2' and '2' for the 14th and 15th characters. The XSP doesn't respond to the 22 (goto command) it responds to the 20 (activate link command). Also, it must see a string that starts with PU8904 before it even continues to analyze the rest of the string. You might want use UPStart to change the set up of those buttons to make them "activate link" command buttons.