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DAA (SPC700): Difference between revisions

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'''DAA''' (Decimal Adjust for Addition) is an [[SPC700]] instruction that performs the following:
'''DAA''' (Decimal Adjust for Addition) is an [[SPC700]] instruction that corrects a [[BCD]] sum:


# If either the [[carry flag]] is set or the [[accumulator]] exceeds 0x99, add 0x60 to the accumulator and set the carry flag.
# If either the [[carry flag]] is set or the [[accumulator]] exceeds 0x99, add 0x60 to the accumulator and set the carry flag.
# Then, if either the [[half-carry flag]] is set, or the lower nibble of the accumulator exceeds 0x09, add 0x06 to the accumulator.
# Then, if either the [[half-carry flag]] is set, or the lower nibble of the accumulator exceeds 0x09, add 0x06 to the accumulator.
The SPC700 has no [[decimal mode]].


==== Syntax ====
==== Syntax ====
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=== See Also ===
=== See Also ===
* [[DAS]]
* [[DAS]]
* [[BCD]]


=== External Links ===
=== External Links ===

Revision as of 22:22, 4 August 2024

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

DAA (Decimal Adjust for Addition) is an SPC700 instruction that corrects a BCD sum:

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

The SPC700 has no decimal mode.

Syntax

DAA
DAA A

See Also

External Links

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