Pinout for 7 pin bidirectional midi?

fret

Experienced
I'm still hunting for the pin out for 7 pin bidirectional midi with phantom power for my foot controller design. It's currently working fine with 2x5pin midi i/o and 9v supplied separately but I'd like to go 7 pin if I can. I've built my ports based on the standard midi<->uart circuit:
midi_iot.gif


I'm assuming I need to take the midi out pin 4 and 5 and wire them to the midi in pins 1 and 3, but which way around do they go?

I can work out the phantom power myself... just need to get around to it. But I'd like to know for sure which way the midi out pins go.
 
I would love to know the answer to this question as well....!

Would allow me to get rid of the second 5 pin midi cable in order to have my midi controller work with the Axe tuner.
 
Maybe I misunderstood you? I´ll try to answer the best I can. If anything is incorrect in my post, please chime in and enlight us all!

Do you mean that you thinking about getting a 5 pin connector in one end, and 7 pin connector in the other end? How would you solve that?
As you can see in the schematic the pins 4/5 are the ones that are being in use in regard to the midi protocol. Pin 1/3 = NC (not connected), pin 2 = ground (on the outputs).

There are some manufacturers that have been using the non-standard way regarding phantom power using the regular 5-pin connectors. Where pin 1/3 supplies power to their products. However since that isn´t a standard there are many other products around that aren´t compatible with this phantom power method... (it even could mean that this method may ruin your non-compatible products because you can never be sure that these product will have any protection circuit on pin 1/3, since you can´t really be sure that these pins are NC in their products).

Besides that, there are many regular midi cables out there that don´t even have 5 leads within the cable, instead they´re manufactured of cables with 3 leads. Which you may or may not be aware of with any of your midi cables.

Since it´s a bit risky to have a circuit with 5-pin connectors with power supply implemented. Fractal choosed to implement a 7-pin connector instead. A regular midi cable with a 5-pin connector can easily fit into the 7-pin connector, but it won´t ever pass on any power coming from the 7-pin connector in the Axe. So there´s a less risk that your midifoot controller will become damaged because of this phantom power.

There are some midi foot controllers out there that have 7 pin connectors, to be able to be used with phantom power. If you are building your own foot controller, I would recommend that you use a 7-pin connector as well, as you then saves yourself trouble regarding your midi cables. It´s possible to buy a spare 7-pin midi cable in music stores if you suddenly realise that you´re out of such a cable...

/Mike
 
miketheman said:
There are some midi foot controllers out there that have 7 pin connectors, to be able to be used with phantom power. If you are building your own foot controller

Yes I have...

miketheman said:
I would recommend that you use a 7-pin connector as well, as you then saves yourself trouble regarding your midi cables. It´s possible to buy a spare 7-pin midi cable in music stores if you suddenly realise that you´re out of such a cable...

I have a 7 pin DIN midi out port on my controller, and a 5 pin midi in. Currently the pins on the midi out are as follows:
1 - NC
2 - Ground
3 - NC
4 - +5v
5 - UART via inverters
6 - NC
7 - NC

So it behaves the same as a 5 pin port. Now obviously 6 & 7 will be connected to power eventually but it's pins 1 and 3 that the axefx sends midi on, and I'm not sure how to wire up those pins such that it acts as the midi in port. I'd like to use the single 7pin midi cable for power, midi out and midi in, ala the MFC-101.

The options are:
1 - midi in pin 4
3 - midi in pin 5

-OR-

1 - midi in pin 5
3 - midi in pin 4

Someone knows which it is???
 
fret said:
The options are:
1 - midi in pin 4
3 - midi in pin 5

-OR-

1 - midi in pin 5
3 - midi in pin 4

Someone knows which it is???
Hi Fret,

it's
1 - midi in pin 4
3 - midi in pin 5

regards,
Xavier
 
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