0000h-7FFFh: bank free region

The system software of the CEPT MUPID (decoder software, BASIC interpreter, graphics) and user RAM areas are located in this region.

8000h-FFFFh:  banking region]
This region has four banks of 32K dynamic RAM each. Each bank occupies the same address area. A bank select determins which bank is actually accessed.
Bank 0: Screen area
Bank 1: Screen area and buffers
Bank 2 and 3: user area, e.g. Bank 2 - BASIC program code, Bank 3 BPES (Basic IDE)

Free memory areas:

The BASIC programmer can use the following memory areas for their own applications (assembler subroutines):
- 7600h-77FFh (511 Bytes): This (bank free) memory area is at the disposition of the user. Some utilities have been located in this area.
- TOPMEM is a user selectable part of Bank 2 or Bank 3. The standard topmem address is FD60h, this can be changed with the OPTION TOPMEM directive in the BASIC compiler
- The other RAM bank. At runtime, only one bank is used (usually Bank 2). For this reason bank read and write commands have been introduced (READ #0, WRITE #0, SETPOS #0, GETPOS #0, PEEK #0, POKE #0) which allow the use of the complete other bank (32K !!!)

Occupied memory areas:
- Bank 2
- Bank 3: If you work with the BPES environment, this bank is completely used by BASIC system routines (compiler, editor, clear text memory ...)
- 7D20h - 7FFFh: Used by the BASIC interpreter (program headers and stack)