Maximum number of MID I/O?

[FantomXR]

Hey people,

just a simple question: I have a use-case where I need 8 MIDI I/Os. Is this possible with the STM? What I read on ucapps is, that 4 I/Os are maximum. I wonder if there is an option to extend those MIDI I/Os.

Thanks,
Chris

[latigid on]

Not enough UARTs for 8 MIDIO. You can expand with I2C (up to 8 output ports, perhaps inputs as well but normally only ins are used).

[FantomXR]

Hey!
Thanks! I just discovered, that Ploytec sells the GM5 in sets of 5 for 33€/5pc. I think I will take that solution! 

[Antichambre]

Or you just wait a few... I've got a surprise .

 

[latigid on]

I didn't want to spoil it!

[FantomXR]

Thanks for the link!

This is not what I need. I need to make my own PCB because I'll integrate a circuit that allows transmitting MIDI over 50m via Ethernet. I'll just take two GM5 and I'm fine. That should work! :-)

[Antichambre]

Just now, latigid on said:

I didn't want to spoil it!

No no don't worry, my fault I kept it secret, but it's ready now!
 

Just now, FantomXR said:

I need to make my own PCB because I'll integrate a circuit that allows transmitting MIDI over 50m via Ethernet. I'll just take two GM5 and I'm fine. That should work! :-)

No SPI port on your "circuit"?

[FantomXR]

Not yet. But as I said: I don’t need classic midi in / miidi out. I need Ethernet :-)

Edited August 13, 2018 by FantomXR

[Antichambre]

19 minutes ago, FantomXR said:

Not yet. But as I said: I don’t need classic midi in / miidi out. I need Ethernet :-)

Kissbox so.

[FantomXR]

Although I have a RTP-OEM I will not use it in this case. 

I’ll use 2xGM5, which gives me 10 MIDI I/Os in total. 

I found that page which shows an easy way, how to transform MIDI into Ethernet and back to midi:

https://www.edn.com/design/consumer/4368054/Send-MIDI-signals-over-long-distances

Only a few parts are needed. Seems to be perfect because I still have some pins on the Ethernet-connector left to also transmit +5V and GND. 

[Antichambre]

Ah ok this is not ethernet! You will just use Cat5e cable to transmit a "balanced" MIDI. like the RS422 is the balanced version of the RS232
This is just an extender, that's great.

[FantomXR]

Yeah! It’s not “real” Ethernet. But it seems to be a great option! Everything in one Cable (In / Out / Power). 

I today finished the reverse engineering of the official GM5-PCB from ucapps. From there I’ll create my special PCB. 

[Antichambre]

You know that you've got the same thing here with the line driver

same principle ;)

best
Bruno

[FantomXR]

I know that. But my use-case still is different and I don't like the big connector :-)