MIDI not working when using SRAM from bootloader program

I’m using essentially the example midi example code from here:

I’m able to receive midi messages properly when running the program from flash, but not when running from SRAM with the same program. I’d like to use midi with some of my larger sram programs. Is there something different you have to do to get this working?

Edit: it might be due to some heavy processing in the audio callback. Will run some tests and update here.

Update: Ran some tests, it’s seems to definitively be running from SRAM that’s causing midi to be unresponsive. Exact same program running in Flash works fine.


Do you happen to know what version of the bootloader you’re using? The older versions (< v6) had some issues with the OLED pins, in which case the screen would appear to not work.

@Corvus_Prudens I’m using the bootloader on the Daisy Web Programmer, as of yesterday.


The web programmer has not been updated in the past 2 years. The bootloader version is v5.4: GitHub - electro-smith/Programmer: WebUSB programmer for Daisy (and other DFU-compatible chips/boards).

Oh wow! I’ll try with the latest version and report back.

Using the latest bootloader from the command line, instead of the one in the web app worked! Receiving midi on my sram program now, thanks all!!

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