MC-50: Checking the ROM version May 02, 2023 08:18 Updated Follow The following procedure can be used to check the ROM version: 1) Power on while holding CANCEL and 0. Related articles MC-50MKII: Updating System Software on External MIDI Devices MC-50, MC-50MKII: Recording Rhythm Patterns Error 12 Messages (Problems when Loading/Saving to Disk) MC-50, MC-50MkII: Loading S-MRC and Standard MIDI Files MC-50, MC-50MKII: Changing individual events in microscope mode.