The connectors are probably serial connectors, but you might want to check the voltages on a few pins to be sure, as sometimes TTL voltages (0 and +5 volts) are used for proprietary interfaces. Check the RXD and DSR pins relative to the GND pin and see if you see somewhere between +5 and +15 or between -5 and -15. Either way, it's probably RS232 serial. If so, you could connect it to a computer serial port, run a terminal program (hyperterm, teraterm, etc.), and hit the enter key a few times. If you get garbled characters back, try changing the baud rate, start bits, parity, and stop bits settings of the terminal program.