Hi Gang. Replying to Robbie's comments following Andy Taylor's
questions on generating MIDI synch pulses.
I'm still working on it, but am now generating pulses using a junk-
box shaft encoder which puts out about 500 quadrature pulses per rev.
This is mounted with a small friction wheel which contacts the upper
feed roll ( Type 'A' Nickelodeon rolls) and now provides about 140
pulses per inch. Pulses are shortened to 160 microseconds using a
type 74121 one-shot IC.
[ That's the MIDI Sync pulse, $F8, I believe. -- Robbie
At Robbie's suggestion, 4 one-shots [operating from the quadrature
signals] could be used to quadruple the pulse rate, which is now
running at about 200 pulses per sec at normal playing speed. Will
be glad to take a picture of the encoder installation, scan and send
to Andy if helpful.
Am still having problems getting my keyboard's MIDI output to talk to
the computer running 'Encore' software. When that problem is overcome,
I should be able to make MIDI files on floppies from 'A' rolls, or go
nuts trying to make it work !
Lee Roan
Temple City, CA
[ Lee is running Windows 3.1, but he also has a pure DOS computer,
[ too. Can anyone advise him how to get Encore running? -- Robbie
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