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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.