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title: "The Flags Register (Part 3)"
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excerpt: "Third installment of a 12-part machine code programming series. Explains the Z80 Flags register bits (Sign, Zero, Half-carry, Parity/Overflow, Add/Subtract, Carry), with focus on the Zero flag and the combination of bit-test and branch instructions."
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    title: "Syntax/Syntax ZX80 v3 n3"
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pubdate: "March 1982"
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---

# The Flags Register (Part 3)

Third installment of a 12-part machine code programming series. Explains the Z80 Flags register bits (Sign, Zero, Half-carry, Parity/Overflow, Add/Subtract, Carry), with focus on the Zero flag and the combination of bit-test and branch instructions.