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What happens when a read is executed when data is not assigned to RAM?

Latest Updated:07/04/2003

Question:

(CPU)   What happens when a read/write access is executed when the data pointer specifies an area that is not assigned to RAM?

Answer:

If a write access is executed when the data pointer specifies a non-RAM area, the value of the RAM will not change. However, if a read access is executed, the value of register A will be undefined. Note that operations executed by a result of read/write (exclusive or operation by register X, register Y operation, and the resulting skip process) will be performed. (#105010)
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