< Also, I seem to recall that North Star DOS was generated for a specific < size -- I believe it's top-resident. A DOS set up for 16K would work on < or 48K, but not vice versa. No it isn't. The controller fills the e800h to efffh space but NSdos is ORGed for 2000h and up. CPM is top resident and for the NS* that usually means a 58k maximum system unless there are some tricks appled. Allison