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4MB expansion kit


4 MB DRAM internal memory expansion for CPC6128.

  • Its first 512 Kbyte are compatible with external memory expansions (Dk'tronics, Inicron RAM expansion, SYMBiFACE II etc.), using port #7Fxx (see Standard Memory Expansions).
  • Its first 2 MB are compatible to RAM7's 2 MB expansion.
  • The whole 4 MB can be used trough ports #78xx to #7Fxx (see CPC4MB Page, for futher details).
  • the expansion connects to the PAL inside the 6128.
  • all configuration codes are supported (0-7) and work exactly as they do in a 6128.
  • I/O port decoding is: 0xxxxbbbxxxxxxxx (confirmed by TFM) where bbb are 3 bits of the bank. The other 3 bits are from the data decoded as 11bbbccc and ccc the configuration code. Yarek's site recommends that bits A14,A13,A12,A10 are set to 1 to avoid conflict with other hardware.



Altrough CPC4MB can be ordered fully assembled (even with mounting on a CPC board), there's still a download of PCB design on CPC4MB page, if you want to DIY.


See also the list of memory expansions for the CPC