Difference between revisions of "Z80 Routines:Optimized:reverseA"
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(New page: reverseA reverseA reverseA This is a faster/smaller (and also obfuscated) replacement for t...) |
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| − | [[Category:Z80 Routines:Optimized| | + | [[Category:Z80 Routines:Optimized|ReverseA]] |
| − | [[Category:Z80 Routines:Graphic| | + | [[Category:Z80 Routines:Graphic|ReverseA]] |
| − | [[Category:Z80 Routines| | + | [[Category:Z80 Routines|ReverseA]] |
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This is a faster/smaller (and also obfuscated) replacement for the normal reverse a. | This is a faster/smaller (and also obfuscated) replacement for the normal reverse a. | ||
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;18 bytes and 66 clock cycles | ;18 bytes and 66 clock cycles | ||
;author: calcmaniac84 | ;author: calcmaniac84 | ||
| − | + | ReverseA: | |
ld b,a | ld b,a | ||
rrca | rrca | ||
Revision as of 15:15, 26 October 2009
This is a faster/smaller (and also obfuscated) replacement for the normal reverse a.
Typical routine:
;input: b ;output: a ;25 bytes, 96 clock cycles typicalreversea: rr b rla rr b rla rr b rla rr b rla rr b rla rr b rla rr b rla rr b rla ret
Better routine:
;- Reverse a ;input: byte in A ;output: Reversed byte in A ;destroys B ;18 bytes and 66 clock cycles ;author: calcmaniac84 ReverseA: ld b,a rrca rrca xor b and %10101010 xor b ld b,a rrca rrca rrca rrca xor b and %01100110 xor b rrca ret
