Use swap in stead of 4 rotations in BCD lesson#123
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avivace merged 1 commit intogbdev:masterfrom Jul 8, 2025
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quinnyo
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It's a good change for the code. And I think a reader that doesn't know either swap or rrca might even have an easier time with the single swap.
| rrca | ||
| rrca | ||
| rrca | ||
| swap a ; Move the upper nibble to the lower nibble (divide by 16) |
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This comment just explains what swap does (rather than why it's being used). Perhaps mention e.g. "move the tens digit to the low nibble"
Also, now that I think about it, 'divide by 16' might be a bit confusing in the context -- it's a divide by ten in BCD.
avivace
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LGTM, @hollannikas maybe just solve the issue that @quinnyo raised?
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I think this saves bytes, cycles and doesn't mess with the carry flag.