We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS

DAA (SPC700): Difference between revisions

From SnesLab
Jump to: navigation, search
(accumulator addressing)
(→‎External Links: Table C-14)
Line 45: Line 45:


=== External Links ===
=== External Links ===
* Official Super Nintendo development manual on DAA: [https://archive.org/details/SNESDevManual/book1/page/n233 Appendix C-8 of Book I]
* Official Super Nintendo development manual on DAA: Table C-14 in [https://archive.org/details/SNESDevManual/book1/page/n233 Appendix C-8 of Book I]
* [https://archive.org/details/SNESDevManual/book1/page/n180 page 3-8-2 of Book I] lbid
* [https://archive.org/details/SNESDevManual/book1/page/n180 page 3-8-2 of Book I] lbid
* ares source code, SPC700::instructionDecimalAdjustAdd
* ares source code, SPC700::instructionDecimalAdjustAdd

Revision as of 10:05, 20 November 2023

Basic Info
Addressing Mode Opcode Length Speed
Accumulator DF 1 byte 3 cycles
Flags Clobbered
N V P B H I Z C
. . . . .

DAA (Decimal Adjust for Addition) is an SPC700 instruction that performs the following:

  1. If either the carry flag is set or the accumulator exceeds 0x99, 0x60 is added to the accumulator and the carry flag is set.
  2. Then, if either the half-carry flag is set, or the lower nibble of the accumulator exceeds 0x09, 0x06 is added to the accumulator.

See Also

External Links