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Block Move Addressing: Difference between revisions
From SnesLab
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* the accumulator will contain the value $FFFF. | * the accumulator will contain the value $FFFF. | ||
* both index registers will point to the byte one past the end of the blocks they were pointing to | * both index registers will point to the byte one past the end of the blocks they were pointing to | ||
* if the source and destination blocks do not overlap, the source block is still intact | |||
==== Syntax ==== | ==== Syntax ==== | ||
Revision as of 02:25, 14 July 2024
Two instructions use Block Move Addressing on the 65c816:
The total number of bytes copied is the value in the C accumulator plus one. If a block move is interrupted, the current byte copy is completed, then the interrupt is serviced.
When the copying is complete:
- the accumulator will contain the value $FFFF.
- both index registers will point to the byte one past the end of the blocks they were pointing to
- if the source and destination blocks do not overlap, the source block is still intact
Syntax
Asar:
MVN srds
References
- Eyes & Lichty, page 388: https://archive.org/details/0893037893ProgrammingThe65816/page/388
- "Block Moves" on page 103, lbid: https://archive.org/details/0893037893ProgrammingThe65816/page/103
- section 3.5.9 of 65c816 datasheet, https://westerndesigncenter.com/wdc/documentation/w65c816s.pdf