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'''ADD''' is an assembly instruction. It | '''ADD''' is an assembly instruction. It adds the contents of the memory location pointed to by the [[effective address]] to the [[A register]], leaving the result in the A register. | ||
== Flags affected == | == Flags affected == | ||
The [[carry indicator]] ('''C''') is set to 1 if a [[Wikipedia:Carry (arithmetic)|carry occurs]] from the sign bit positions of the adder, otherwise the carry indicator is reset to 0. If the signs of the two operands are equal, but the sign of the result is different, overflow has occurred, and both the [[dynamic overflow indicator]] (''' | The [[carry indicator]] ('''C''') is set to 1 if a [[Wikipedia:Carry (arithmetic)|carry occurs]] from the sign bit positions of the adder, otherwise the carry indicator is reset to 0. If the signs of the two operands are equal, but the sign of the result is different, overflow has occurred, and both the [[dynamic overflow indicator]] ('''Q''') and the [[static overflow indicator]] ('''O''') are set to one. If the condition for overflow does not exist, the dynamic overflow indicator is reset to 0, while the static overflow indicator is left unchanged. | ||
Latest revision as of 14:54, 30 June 2010
| ADD | |
|---|---|
| Description | Add to A register |
| Format | ADD <addr. mode> <disp.> |
| Code | 060 0008 |
| Affected | A:=A+(ea), C, O, Q |
| Type | User |
| Architecture | ND-100, ND-110 |
ADD is an assembly instruction. It adds the contents of the memory location pointed to by the effective address to the A register, leaving the result in the A register.
Flags affected
The carry indicator (C) is set to 1 if a carry occurs from the sign bit positions of the adder, otherwise the carry indicator is reset to 0. If the signs of the two operands are equal, but the sign of the result is different, overflow has occurred, and both the dynamic overflow indicator (Q) and the static overflow indicator (O) are set to one. If the condition for overflow does not exist, the dynamic overflow indicator is reset to 0, while the static overflow indicator is left unchanged.
References
- Norsk Data Document ND–06.014.02 ND-100 REFERENCE MANUAL Page 135
- Norsk Data Document ND–06.029.01 ND-110 Instruction Set Page 65