NEC 78K/0 Series - Manual (Page 56)

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CHAPTER 5 EXPLANATION OF INSTRUCTIONS
User's Manual U12326EJ4V0UM
Add with Carry
ADDC
Addition of Byte Data with Carry
[Instruction format] ADDC dst, src
[Operation] dst, CY ← dst + src + CY
[Operand]
Mnemonic Operand(dst,src) Mnemonic Operand(dst,src)
ADDC A, #byte ADDC A, !addr16
saddr, #byte A, [HL]
A, r Note A, [HL+byte]
r, A A, [HL+B]
A, saddr A, [HL+C]
Note Except r = A
[Flag]
Z AC CY
Ч Ч Ч
[Description]
• The destination operand (dst) specified by the 1st operand, the source operand (src) specified by the 2nd
operand and the CY flag are added and the result is stored in the destination operand (dst) and the CY flag.
The CY flag is added to the least significant bit. This instruction is mainly used to add two or more bytes.
• If the addition result shows that dst is 0, the Z flag is set (1). In all other cases, the Z flag is cleared (0).
• If the addition generates a carry out of bit 7, the CY flag is set (1). In all other cases, the CY flag is cleared
(0).
• If the addition generates a carry for bit 4 out of bit 3, the AC flag is set (1). In all other cases, the AC flag
is cleared (0).
[Description example]
ADDC A, [HL+B]; The A register contents and the contents at address (HL register + (B register)) and the
CY flag are added and the result is stored in the A register.