> Similarly, the korg volca FM firmware update procedure happens by playing an audio file into one of the sync input jacks. The Volca FM uses Quadrature Amplit

> Similarly, the korg volca FM firmware update procedure happens by playing an audio file into one of the sync input jacks. The Volca FM uses Quadrature Amplitude Modulation[0] to encode/decode digital data. Korg released the source code to an encoder on Github[1] for people to use with the Volca Sample. A few people have used this to write a decoder for the firmware, most notably Pajen who used it to write the custom firmware for the Volca series. > This is odd considering it has a MIDI input port, which could load firmware via digital SYSEX commands, a fairly common method. The Volca series has lots of really odd design quirks, and overall I'm pretty critical of a lot of them. In this case I think they made the right choice. SysEx has a very low transfer speed. Transmitting even a few kb takes a noticeable period of time, and the Volca firmware blobs are 256kb in size. The Cypress FM4 SoC they used doesn't have an integral USB controller either, so I guess they had to get creative! 0: https://en.wikipedia.org/wiki/Quadrature_amplitude_modulation https://en.wikipedia.org/wiki/Quadrature_amplitude_modulatio... 1: https://korginc.github.io/volcasample/documentation.html https://korginc.github.io/volcasample/documentation.html