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DAA (SPC700): Difference between revisions

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'''DAA''' (Decimal Adjust for Addition) is an [[SPC700]] instruction.
'''DAA''' (Decimal Adjust for Addition) is an [[SPC700]] instruction that performs the following:
 
# If either the [[carry flag]] is set or the [[accumulator]] exceeds 0x99, 0x60 is added to the accumulator and the carry flag is set.
# 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 ===
=== See Also ===
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* 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: [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


[[Category:ASM]]
[[Category:ASM]]
[[Category:SPC700]]
[[Category:SPC700]]
[[Category:Decimal Compensation Commands]]
[[Category:Decimal Compensation Commands]]

Revision as of 19:37, 22 July 2023

Basic Info
Addressing Mode Opcode Length Speed
implied 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