I love the TERRA. I think it is a massively underestimated instrument that should be talked much more about.

One reason I  bought it (besides the sound and expressivity) is the tunability, as I am exploring different tuning systems. While it is possible to tune any of the note pads and the transposition keys, it would be much easier to load a tuning (say from a Scala file). Also loading custom made transposition key presets would be great!

I’d like to build a tool that would allow me to bake custom preset files, and I hope you could help me with this.

I have reverse engineered the preset file format, and I could edit it to reflect a desired tuning. However, there is a feature that prevents me from loading a custom preset file, which is a hash value (bytes 13-16 of the preset file), that the firmware is checking against. (If I try to load an adjusted preset file with the hash not matching, the six lights in the triangle light up and the USB mode hangs.) Without knowledge of the hashing algorithm, constructing custom preset files is not possible.

To be able to create my own preset files, I’d either need to know the hashing algorithm used or a new firmware that would not check against the hash value.

Any chances you can help me out?