The 6502 in the PZ1 has 256kb RAM, no ROM. Any ROM contents are copied at startup to the correct place in memory by the emulator.

The memory is divided into 8kb memory banks, with each bank having an 8-bit register to choose where in the 256kb-space it points. It is possible to change memory bank 0 to swap between several Zero pages. Multi-tasking possibilities abound :D

I/O-area is always overlaid at $FE00-$FEFF.