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It was known that there was a 'software hook' in OZ that would allow the Z88 to boot into software written in the external slot 1. The 1M Flash card was the ideal candidate for this, there would be no need to do any hardware modifications on the Z88 at all. Before this could happen, the binary code of OZ 4.0 ROM needed to be disassebledreverse-engineered, re-organised, documented and understood.
During this discovery stage it was found that RAM and Flash could be on one device, hence the 512K/512K Flash/RAM card was developed.
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