Old School 512K RAM Expansion

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A 512KB RAM Expansion for the CPC 6128 and Plus.

Old School 512KByte RAM Expansion for CPC6128 and Plus

This is a DK'Tronics compatible 512K RAM expansion board built using standard 74 Series logic ICs and a single SRAM chip. There are no devices which need programming and all parts are in through-hole packages to make for a board which is easily assembled even by a beginner.

This card supports all 6128, 464 Plus and 6128 Plus machines but is not suitable for the older 464 and 664 computers.

The board is fully compatible with the DK'Tronics/Amstrad bank switching schemes described in the DK'Tronics Peripheral Technical Manual.

Electrically, the card is very low power. In typical use it draws only a couple of mA of current which is less than a tenth that taken by other CPLD based cards. The SRAM and HCT logic components are also very tolerant of low supply voltage and the card has been tested to work even as low as 3.5V.

The card has a Mother MX4 standard box connector rather than an edge connector. So to use the board you will need a Mother X4 or compatible expansion card.

This is a fully open source project and all code and further documentation is available on the project's GitHub pages and wiki.

The bare PCB is available from SeeedStudio via their Seeed Gallery pages.

Bare PCBs or fully assembled cards may from time to time be available also directly from Revaldinho - please PM via the Discussion Forum to check.