GM833 - 512K RAM Disk Card
This interesting card simulates disk drive of 512k. It was address via Z80 ports in a track / sector manner making interfacing extremely simple from a software point of view. Each logical sector is mapped to 128K bytes, making this perfect for CP/M.
Up to 16 boards could be added giving a huge (for the time) 8MB disk which was the largest addressable. It should be note that this was not really possible due to power consumption and bus length issues.
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