5.1.4. Read-lock-write

The IDC treats the Read-Locked-Write instruction as a special case.

The read phase

always forces a read of external memory, regardless of whether the data is contained in the cache.

The write phase

is treated as a normal write operation. If the data is already in the cache, the cache is updated.

Externally, the two phases are flagged as indivisible by asserting the BLOK signal.

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