Two upperROM set : if you press "space" during a reset_key ("page up" key), upperROM files used are *.f00 to *.fFF instead of *.e00 to *.eFF.
*.eZZ is still used in both case.

Personnaly I have :
- ParaDOSv1.2.f07
- BASIC1-1-french.f00
- MAXAM.e05
- PROTEXT.e06
- ParaDOSv1.2.e07
- BASIC1-1-french.e00
- OS6128-french.eZZ

By using this functionality I can insert PROTEXT and MAXAM ROM by default, and still play Asphalt after a "space"+"page up" quick reset.