Standard MIDI In/Out, Thru Circuit

[Satch12879]

This one's for the major league gurus; is there a STANDARD schematic for a MIDI IN/OUT, and THRU circuit.  You know the one like you'd find on the back of a synth or a piece of rack gear.  I've found a MIDI Thru schematic but have no way of verifying it's authenticity or appropriateness.  There's an interface I'm working on designing and I'd like to include a MIDI feed to interface a footcontroller to a rack.  Lots of times you'll see the pass through done passively on DIY interfaces just as straight wire from the front of the rack to the back, but that's a pretty foul idea as the MIDI standard has a maximum length before losses add up into errors.

Figure since MIDI is a universal, standardized language, there has to be a standard circuit for powered interfaces.

Thoughts? Suggestions?

[Dave_B]

Regarding the Midi Thru, here's a schematic for a non-µC circuit.  After that, things start getting pretty specific based on the controller you use and what you're trying to do.  There are things you can do without a micro, but most things of any complexity will require one. 

[Satch12879]

Thanks, it's very similar to one that I found searching around.

It doesn't need to do much of anything except provide an interface for MIDI signals over lines between pieces of gear, no routing or matrix functions, just an active node.