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Arithmetic Group Instructions (Part-II)

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ADI 8-bit data:
  • This instruction adds the 8-bit data given within the instruction itself to the contents of the accumulator.
  • The result is stored in the accumulator.
  • All flags are modified.
  • It is a two byte instruction.
  • Immediate addressing mode is used.
Example:
If A = 20H
ADI 56H ; This instruction adds the contents of A (20H) to 56H and result 76H is stored in A.

ACI 8-bit data:
  • This instruction adds the 8-bit data given within the instruction itself and the carry flag to the contents of the accumulator.
  • The result is stored in the accumulator.
  • All flags are modified.
  • It is a two byte instruction.
  • Immediate addressing mode is used.
Example:
If A = 30H and CY = 1
ACI 20H ; This instruction adds the contents of A (30H) to 20H with carry (1) and result 51H is stored in A.

DAD Rp:
  • This instruction adds the contents of specified register pair to the contents of HL register pair.
  • The result is stored in HL register pair.
  • Rp is 16-bit register pair like BC, DE, HL or SP.
  • Only higher order register is specified for the register pair.
  • Only carry flag is modified.
  • It is a one byte instruction.
  • Register addressing mode is used.
Example:
If DE = 1000H and HL = 2000H
DAD D ; This instruction adds the contents of DE (1000H) with HL (2000H) and result (3000H) is stored in HL.
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