CPC iRAM

CPC iRAM is a series of open source, DIY friendly, internal RAM expansions for the CPC 6128 (later hopefully also for the 464 and 664).

The iRAM expansion sits in the CPU socket and requires no additional soldering inside the CPC.

The first 512K of expansion RAM follow the DK'Tronics addressing mode standard, giving up to 576K of RAM to legacy software. More modern software that supports the extended 1M-4M standard will be able to access all the provided RAM.

CPC iRAM/640

for CPC 6128 only
512K expansion
total accessible RAM of 640K in a 6128 (64K Base RAM + 512K RAM expansion + 64K secondary RAM bank of the 6128)
easy to assemble, all through-hole components
fits into a CPC 6128. In Schneider CPC 6128 the metal shielding needs to be removed or altered.

Status: Final PCB tested. Release of the iRAM 640 documentation/DIY guide is planned for early 2025.

Status: abandoned as the same components are required as for iRAM/640 with only minimal changes to the PCB and GAL logic.

for CPC 6128 only
1024K expansion
total accessible RAM of 1088K in a 6128 (64K Base RAM + 1024K RAM expansion)
easy to assemble, but some SMD components due to size constraints in the CPC 6128

Status: Prototype successfully tested. Release can be expected in Q1/2025.

for CPC 464/664
512K expansion
total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
easy to assemble, all through-hole components

Status: Prototype testing not yet successful. Release not before mid 2025.