Fluxamasynth-32 with SD Card

Interfacing hardware, sensors, output drivers, chips.
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flossnmeditate
Posts: 5
Joined: Fri Jul 12, 2019 10:10 pm

Fluxamasynth-32 with SD Card

Post by flossnmeditate » Fri Jul 12, 2019 11:29 pm

Anyone had any success getting a SD card adapter to work with a Fluxamasynth-32?
I'm hoping to play MIDI files from the SD card but concerned that the MOSI and MISO ports might already be taken with the audio chip on the Fluxamasynth?

Any thoughts?

paul
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Re: Fluxamasynth-32 with SD Card

Post by paul » Mon Jul 15, 2019 10:49 am

The SPI pins are entirely free on that board. The only connection between the dream chip and the uC is on pin 4 for sending serial info (at midi speeds) and pin 5 for receiving serial from the midi jack (if present).

Paul

flossnmeditate
Posts: 5
Joined: Fri Jul 12, 2019 10:10 pm

Re: Fluxamasynth-32 with SD Card

Post by flossnmeditate » Mon Jul 15, 2019 3:32 pm

Fantastic, i'll get noodling...

And to then attach an LCD display which requires connection to: SDA & SCL, usually pins 21 and 22, any suggestion as to how would i access these?

paul
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Joined: Mon May 12, 2008 4:19 pm

Re: Fluxamasynth-32 with SD Card

Post by paul » Mon Jul 15, 2019 9:13 pm

The SDA and SCL pins are a bit of problem. Shawn Wallace (the designer of the current version of the board) informed me that he had used an out of date doc on the ESP WROOM which had either SDA or SCL mislabelled. So this one will require adding a wire from the ESP module.

Of course (to push our own hardware) moderndevice has a nice little serial based LCD driver, the LCD117 for character displays so this would be an option. Otherwise, you'll have to run a wire from the ESP to a pin that you don't plan on using for the connector. We'll test this and revise the board when we start to get low on the current revision.

flossnmeditate
Posts: 5
Joined: Fri Jul 12, 2019 10:10 pm

Re: Fluxamasynth-32 with SD Card

Post by flossnmeditate » Tue Jul 16, 2019 6:03 am

Fantastic info Paul, i'm loving your response time! Thank you so much and thank you also to Shawn Wallace, you're a legend.

Your post sent me down a rabbithole today, i tried a bunch of different things and my end solution works great, it goes like this...
  • Connect pin 17 from a standard separate esp32 to the midi-in pin on the fluxamasynth.
    Chop the connection from the onboard esp32 pin 17 to the midi chip.
    Upload code to seperate esp32 and have ALL the pins (apart from 17) available for LCDs, LEDs, SD Cards, etc etc..
fluxamagogo.png
Bench looks like...
Happy days, thankyou.

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