'SPIFFS' was not declared in this scope

This error may occur when you try to compile a sketch that uses the SPIFFS library.

SPIFFS is used in SimBox project to store PIN numbers in board memory. This is additional feature and not really critical.

In some cases steps from this article helps users.

However, if you struggle with this issue, you can just use version of SimBox knob code that does not use SPIFFS library.

You can find it in file dump under
{file dump location}/knob/arduino/simbox-no-storage/simbox-no-storage.ino