[sdiy] 3.3V and MIDI

[Colin f]

> -----Original Message-----
> From: owner-synth-diy at dropmix.xs4all.nl 
> [mailto:owner-synth-diy at dropmix.xs4all.nl] On Behalf Of Ullrich Peter
> Sent: 07 June 2003 1:14
> To: Bert Schiettecatte; synth-diy at dropmix.xs4all.nl
> Subject: AW: [sdiy] 3.3V and MIDI
> 
> 	As the MIDI interface is a current interface (nominal 
> 5mA) it should be 
> 	no problem as long as the current can be sinked on the 
> MIDI outport. But
> you will have to adjust the resistor (normally 220 ohms) 
> values so that the
> current of 5mA can flow.
> 	Remember that the receiver also has a 220 ohm resistor 
> on teh input.

That's true so long as the voltage drop on the LED in the input
opto-isolator is less than 3.3v.
I'm pretty sure it will be tho'.
The current is not just set by the resistor.

Colin f