MIDI clock jacks IN & OUT ... schematics ?

[fff]

Hi All,

I found here and there the schematics to connect DIN-5 IN and OUT --> this si clear and working very well
But what if I want to connect 2 small jacks to create a clock in and another for out ? (idea is to sync without the midi din-5 ports, as in many hardware setups)

How do I connect these jacks to a T4.0 for example ... no directly I guess ?

(yes you got it, I am not an electronic engineer)
Thanks,
F

 

[blakeAlbion]

The electronics for clock IN and OUT are simple, but not consistent.
Generally you can expect a "TTL" level signal to work, meaning logical HIGH is close to 5V and LOW is close to ground.
This means for a Teensy you could use optocouplers where the output transistor emitter is grounded an the collector is "pulling down" a pull-up resistor (10K-4.7K).
The Teensy then just drives the LED in the optocoupler using a modest amount of current (make the LED resistor be > 470 Ohm if possible).

You could use a single transistor directly but the optocoupler approach keeps your Teensy's pins away from that mean old 5V supply.
See the simple transistor buffers used in the Roland CR-8000 to support "DIN Sync".