Connecting picocalc to MIDI Synthesizer Module

PicoCalc
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Using the side pins of the picocalc, I successfully played MIDI sounds on mmbasic.

I configured the GP28 pin as a software UART output, sending a 31250bps signal to the MIDI Synth module. While GP28 could likely be assigned to the hardware UART, I abandoned that idea since UART1 was already in use for the serial console via another pin.
(Is there a way to use the hardware UART?)

The Synth module is Kinoshita Laboratory’s “MIDI-guy” (the red board on the left, equipped with SAM2695). I plan to integrate this and force the audio output to the speaker.

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Next step will be a tracker app on the pico :smiley:! Great job!

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Thank you!
I’ve seen tracker apps before, but I’ve never actually used one myself…

For now, I’ve managed to parse and play SMF Format 0 .MID files.
Since I’m handling wait times with `pause`, game music with lots of messages happening at once ends up sounding slow, but piano pieces play just fine.

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That midi module looks great! A tracker app would be so good. The PicoCalc’s keyboard would be great for note entry.

A euclidian sequencer or another kind of generative midi program would be a fun project to build.

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grbzng, thank you!

Using Settick instead of Pause improved the tempo drift somewhat.
However, perhaps because I’m using software UART, the tempo still slows down as the number of notes increases.
I tried to use hardware UART to increase processing speed. But I couldn’t disable the serial console function (which connects to a PC terminal software via USB serial) that occupies it.
This is proving quite difficult…

Reference 1: The “Serial Console” section in the Picomite user manual
Reference 2: Unofficial PicoCalc PicoMite/WebMite firmware release thread (V6.00.02) - #216 by Toml_12953

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If you compile the source code yourself, look in MM_Misc.c around line 3981.

To regain control of your serial ports, comment out these lines:

//            Option.SerialConsole = 1;
//            Option.SerialTX = 1;
//            Option.SerialRX = 2;
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