sync24 specifications

[Byron G. Jacquot]

>Most of my gear operates reliably up to 300 BPM.
>At 24 PPQ, thats 8.33ms per cycle or 4.17ms On-time per pulse at a 50% Duty
>cycle.
>
>I think I remember reading somewhere that even 2ms On-time is fairly stable
>with most gear.

Of the DIN boxes I've ever used, I think the TR808 is the most picky.  I've
got a MIDI-CV/DIN box that outputs a fixed width pulse when it recieves a
MIDI clock tick.  I think it's 2 mS, but I'd have to check it to make
sure...the 4 mS mentioned ablve might be wide enough to guarantee that it works.

(thinking from a programmatical standpoint, the DIN clock line probably
interrupts the processor, telling it that it's time for the next step.  From
the schems I've seen, it's not synchronized with a latch/flipflop.  But most
processors only interrupt between instructions...as old as they are, and as
slow as they are, the processors in those old boxes might spend considerable
periods where they can't be interrupted...just a theory as to why this happens)

2 mS is too narrow to reliably sync a TR 808!  It starts to miss clock
pulses, and lags behind.  I've been thinking aobut stretching the pulse with
a monostable multivibrator, but have a lot of other things on my plate right
now...and have other means of reliable DIN sync.

Byron Jacquot