[sdiy] midi clock

[Tim Ressel]

Yo,

Datasheet for CDP6402 (IM6402):

http://www.electronic-projects.net/data/cdp6402.pdf

Available at BG Micro for $2.45

--tr

--- Tim Stinchcombe
<tim101 at tstinchcombe.freeserve.co.uk> wrote:
> Hi All,
> 
> >     This is something I just drew up.  I would
> want to run it 
> > through a logic simulator (Logic simulators are
> for Wimps and 
> > Bedwetters, but it does save time) before I would
> call it 
> > complete.  It turned out a lot more complicated
> than it 
> > sounded.  A Pic or AVR solution would probably be
> better.
> > 
> >
>
http://www.silcom.com/~patchell/synthmodulesII/200-1028.pdf
> > 
> >     Anyway, the clock goes into the phone jack.  A
> toggle 
> > switch selects the edge polarity.  The midi event
> will be 
> > transmitted either on the positive or negative
> edge....a PLD 
> > solution would be a little tidier as well
> probably...
> 
> 	Shudder! Because of all this talk of PICs and PLDs
> and things I
> had only been following this thread somewhat
> half-heartedly, but then I
> remembered I had a small book entitled 'Practical
> Electronic Music
> Projects' by R.A.Penfold (Babani, 1994). In it there
> are several simple
> MIDI circuits, one of which is for a control pedal,
> and another for
> detecting any given MIDI byte. Both use a UART chip
> (6402) which seems
> to simplify things considerably. In the pedal
> circuit the appropriate
> bytes are generated using '245 octal transceiver
> chips, tri-stating 3
> bytes in turn to the 6402 - re-jigging the whole
> thing to output the
> appropriate clock byte values, and adding in some
> sort of variable speed
> clock looks more than do-able (and even start/stop
> messages doesn't look
> so bad either). Outputting a pulse to drive an
> analogue sequencer should
> be no big deal, and then adding in a modified
> version of the
> byte-detecting circuit should give a means of
> syncing in the other
> direction too. Just a thought that, to me at least,
> there does appear to
> be an alternative to the PIC/PLD route (in fact I
> think I might just add
> it to my list of projects!). But then of course I
> might be completely
> missing the point somewhere, so somebody please put
> me right if I am!
> 
> Tim
>
__________________________________________________________
> Tim Stinchcombe 
> 
> Cheltenham, Glos, UK
> email: tim101 at tstinchcombe.freeserve.co.uk
> 
> 
> 


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