Ref: Your note of Mon, 24 Jul 1995 20:45:42 -0400 (EDT)
> I take it Pin 1 and Pin 18 do the actual keying
Correct.
> and Pin 17 says this is the LPT port that is selected for CW.
No, CT just sets it high and leaves it there, to provide voltage to
the base of the keying transistor. It's not called "CW Select", it's
called "Select Input" according to the PC Technical References. Real
printers use that line for handshaking with a PC.
Note, for paddle support and for TRlog compatibility, pin 12 (Paper
Out) needs to be reserved for the dot paddle, pin 13 (Select, not
Select Input) for the dash paddle, and pin 14 (Auto Feed) for 10k
pullup resistors to 12 and 13.
73,
Bob, N6TV
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