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.

released

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.

for CPC 464/664
offers two sockets for SRAMs
upgrade to 576K (1 SRAM) or 640K/1024K (2 SRAMS)
first SRAM: Upgrade to 576K, following the DK'Tronics standard without support of C3 mode (like many other RAM expansions)
second SRAM: upgrade to 640K (128K SRAM) or 1024K (512K SRAM)
C3 RAM banking supported if both SRAMs are fitted
easy to assemble, all through-hole components

Status: in active development

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. No final PCB yet. Might be resumed if there's demand.

Status: Abandoned in favor of the iRAM/640 which uses the exact same components but offers more total memory.

for CPC 464/664
512K expansion
total accessible RAM of 512K in a CPC, following the DK'Tronics standard and support of C3 mode.
or 576K without C3 support (512K_C3 / 576K selection per manual switch)
easy to assemble, all through-hole components

Status: currently on halt as CPC iRAM/1024 will fit into all 464s and 664s and is more flexible