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Fred McKenzie · April 14th 10, 08:45 AM posted to rec.radio.amateur.moderated

In article ,
(David Griffith) wrote:

Does anyone here done something like sending ASCII to a microcontroller
which then emits morse code? I'm tinkering around with old telegraph
sounders.

David-

I understand the old telegraph sounders made a clack-clack sound rather
than a beep. They also used an earlier version of code than
international Morse, where some characters had mini-spaces in addition
to dots and dashes.

Either way, the solution may be similar. Use the ASCII code as an
address for locating the timing required for each character, stored in a
look-up table.

Use a basic timing subroutine. Call it once for a dot or a space. Call
it three times for a dash. Before calling it, turn on the output keyer
for Mark and off for Space.

If you didn't have an existing sounder, you could generate another
timing interval that would repeat at an audio rate for the amount of
time the Mark signal would be on.

Fred
K4DII