[sdiy] Adding a 5-pin MIDI DIN connection to a kybd controller with USB

[brianw]

Logan,

Those newer desktop synths that have 5-pin DIN classic MIDI and USB already have a microprocessor to control the synth engine, and USB, and MIDI. The firmware was written to handle all three, and the MIDI is just a serial port with the correct settings and code to pass along the messages, in and out.

Any keyboard controller that has a USB connection built-in will already have a microprocessor, but it might not have a serial port (for MIDI), or if it does have a serial port then the pins might be used for something else, or if they're not used then they still might be inaccessible under the microprocessor chip package. The firmware would have to be rewritten to add 5-pin DIN classic MIDI if it wasn't originally designed into the product. There's a very small chance that your USB keyboard controller already supports 5-pin classic MIDI on the PCB, but you'd have to figure out how to wire it up.

As for your realistic options:

You could replace your keyboard controller with one that has both USB and classic MIDI (or even one that has only classic MIDI).

Apart from that, you could design your studio around a device that can act as a hub for all kinds of MIDI: classic 5-pin DIN, ethernet (RTP-MIDI), and USB-MIDI. This option isn't cheap, but then you don't have to worry about adding new modules or devices that aren't like the rest.

Brian


On Jul 17, 2022, at 7:51 PM, Benjamin Tremblay via Synth-diy <synth-diy at synth-diy.org> wrote:
> You will need a microprocessor like an arduino or pic to be a usb host and convert to 5 pin serial. The Teensy 4 will do this very well.  The Teensy 4.1 has a USB host kit so you could prototype it with usb cables. 
> 
> Benjamin Tremblay
> 
> On Jul 17, 2022, at 10:29 PM, Logan Mitchell Sr via Synth-diy <synth-diy at synth-diy.org> wrote:
>> Does anyone know if a keyboard controller that has a USB connection built-in can have a S-pin DIN MIDI connection added to it and if so how would that be done ?
>> 
>> I have some older 5-pin MIDI DIN modules & two newer desktop hardware synths that have the 5-pin DIN style MIDI connectors built in along with built-in USB connections but I prefer to use the 5-pin MIDI DIN connections for the sake of end to end compatibility as some of the older modules are pre-USB devices.   
>> 
>> Logan