The following procedure can be used to check the ROM version:
- Synthesizer section only - Serial #s through ZE80899
- Press PATCH (in the MODE section).
- Press INFO.
- While holding NUMBER 6, press CURSOR DOWN (V).
- Synthesizer section only - Serial #s ZF00900 and above
- Power on while holding WRITE, NUMBER 1 and NUMBER 8.
- Press the BANK 8 button.
- Sequencer section only
- Power on while holding CANCEL and the '0' button.
Owner's Manual: https://www.roland.com/us/support/manual_archive/