It's been a while since I had one (and looked at the schematics), but I think the TR-808 can respond to data on all 5 pins. The adapter has a male stereo minijack at one end, and a female 5 pin DIN MIDI connector on the other, and is 22 cm / 8. Engineered to preserve tone, they accurately transmit the purest signal without contamination or interference. They could have gotten away with a three pin DIN connector, but I guess they had the two extra pins for future use which never happened (yet).

Plugs into the RK-006 (Or Korg/Yamaha products) and directly provides male DIN5 output to plug into MIDI Gear. I suppose it didn't make sense at the time but looking back I think it would have been smart to keep Din Sync on pins 1-5 and then gone to an eight pin DIN and put MIDI on pins 6-8.Many products make now use of a stereo jack connector, which make use of a breakout cable to the standard 5 Pin DIN MIDI connector. it has a button that disables the internal antennas and uses the car antenna and power via a port on the bottom of the radio. Standards have now been drawn up by the midi association and TYPE A is the accepted standard, but devices made prior to this may be wired with TYPE B or even TYPE C in rare cases.

This setup also allowed me to trigger notes on the NTS-1 simply by pressing the buttons on the SQ-1.So long as you have two pieces of gear wired this way, you can connect them with a standard stereo minijack audio cable (that’s a single stereo minijack at both ends). minijack connector on the product itself, with a breakout cable to a female 5 Pin DIN MIDI connector. I've mainly been using the CV outs with my modular but have been itching to use the 9-16 drum pads for samples/drums using the midi out. This will not work going to midi in, midi merge requires more complex circuitry than midi split(thru boxes).