Topic: Custom ROM and NMI reentry on space address.
The ROM does not have basic in. Assuming an NMI fails as I can't even trace where the "pop af" happens in the spaghetti. I think the "rst 38" and "rst 10" is sorted. If using assembly calls to the routines.
I'm kind of assuming the NMI does not do a return to $67 to exit, and uses some BASIC routines. I think switching to the ROM after boot, does allow a "jp $000a" at $0008, for "rst 10" access to raw assembler esxDOS calls.