I modified a DL30? about 10 years ago. I used Procomm at the time. The serial connection used screw terminals on the back. Just get a straight through serial cable and cut on end off pick up your ohm meter and figure what wires are pins 2,3,and 7 then land them like the book says. If you have the baud rate, parity, and stop bits right and it still will not talk then swap the wires on pins 2 and 3. Download the manual and read it. The main thing I remember was having to hit the escape key two or three times to get the DL to notice that I wanted to program it. The book did not spell that part out for me very well. After you get it into "program mode" the book explained what to do. I bet Windows Hyperterminal will probably work fine. I dont remember how I determined the baud rate etc. probably trial and error.