====== The secret behind cdj's control interface ======

Did u ever ask yourself how does the 3,5mm jack of "CONTROL" interface of cdj's work??

It is located on most CD players of various brands (Pioneer CDJ and so on), and on Dj mixers (Pioneer DJM and so on).

Is that a simple switch or is that some kind of serial protocol ??

=== That's a simple switch!! BUT... ===

But if u try to connect jack's tip with shield it does not work, why?

Because TIP is START, SHIELD is STOP, (ring not used), GROUND REFERENCE IS ON AUDIO PHONO JACKS !!!

So connect jack's tip with audio shield and cd will start. Connect jack's shield with audio shiled and cd will stop!!!

Note: the cdj has internal pullup resistor (input should be ttl compatible).

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