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Table of Contents

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28. Address unit; Memory arbitration

The address unit generates the memory address for the memory controller unit to use to access the DRAM. This address can come from the program counter, the second instruction field of the Jump and Call instructions, or by adding the displacement address of a branch instruction to the current location.

Later I start to think about bus arbitration. This circuit will decide when the CPU can control its own memory, and when it should yield control to the host Z80 so that the host can read/write the memory.