CPC4MB

4MB expansion kit

Description

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 further 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,A11 are set to 1 to avoid conflict with other hardware.
• accessing the upper 2MB of a 4MB expansion requires special caution to avoid conflict with other hardware expansions. See Standard Memory Expansions for details.

Software

• Currently, CPC4MB is supported by FutureOS version .8 or higher
• The 4 MB E-RAM Test: Media:E-RAM_Test_2014.zip
• Giana Sisters Remake
• Captain Future Video Demo
• The first MB of the 4 MB expansion (&7Fxx, &7Exx) is supported by SymbOS.

Schematics

Schematics have vanished together with the CPC4MB website and unfortunately have not been archived anywhere else.

Links

• CPC4MB (mirror on Archive.org)

See also the list of memory expansions for the CPC