Testing a 1488 line driver...

I've got an Ampro Littleboard that I'm trying to bring back to life. Sometime last year it quit transmitting data on Port A (the console port) so I shelved it until I had time to look at it. I've checked the Z-80 DART with a logic probe and I'm seeing data coming out of Port A (Pin 15 on the DART) when the machine boots up. I check the input pin on the 1488, and get the same sound (the logic probe chirps with each state transition) as I get out of the DART. However, checking the output of the 1488, I don't get anything. Since I don't want to blow my probe apart on 12V, I used an LED to watch the output on the 1488. The LED lights the instant I attach it to the output and doesn't flicker or go out when I reboot the computer to make it send data out the port. The Port should be running at 9600 baud, so I should see at least some flicker activity on the LED if the 1488 is toggling the output pin. Before I spend the time to replace the 1488, I'd like to hear from you folks if the chip is actually bad. Is what I'm seeing indicative of a dead 1488? Thanks all! g. -- Proud owner of F-15C 80-0007 http://www.f15sim.com - The only one of its kind.