Teletype 43

Jim Brain brain at
Mon May 22 23:57:58 CDT 2017

On 5/22/2017 8:41 PM, Ethan Dicks via cctalk wrote:
> Do you have a "traffic light"?  I find them invaluable for diagnosing
> handshaking and TxD/RxD swaps.
Yep.  constant low on TX.
> What worked was a serial port on a desktop.  The first try.
It's entirely possible, but I put a scope on the TX line, and I see no 
activity at all with the unit in DATA or TERM READY mode.  The DATA LED 
blinks, so I think I need to signal the Model 43 that it is "connected".

As has been suggested, I joined GreenKeys and asked if someone has a 
similar setup that works, so I can replicate.

Worst case is that the driver board has issues, which at least will 
narrow down my search.


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