On 10/16/2015 01:48 PM, Brad wrote:
When I connected it to my PC running PUTTY via serial cable, I fully expected it to do nothing. But to my surprise, it generates a continuous stream of Js (punctuated by the odd H) on the PUTTY screen if the RECV switch is off. If I hit Break, it generates a whole bunch of Bs. If I switch the RECV switch ON, the Js stop but I can still generate Bs with the Break key.
It sounds like it's time to get the old 'scope out and check the UART clock signal (do you have the TR1602 or the AY-3-1013?) and also the -12V at the chip.
--Chuck
