Source + Destination -->; Destination
ADDX Dy, Dx
ADDX -(Ay), -(Ax)
Attributes: Size = (Byte, Word, Long, Quad)
Description: Adds the source operand to the destination operand
along with the extend bit and stores the result in the
destination location. The operands cas be addressed in two
1. Data register to data register.
2. Memory to memory (Pre-decrement mode)
The size of the operation can be specified as byte, word,
long, or Quad.
X Set the same as the carry bit.
N Set if the result is negative. Cleared otherwise.
Z Cleared if the result is nonzero. Unchanged otherwise.
V Set if an overflow is generated. Cleared otherwise.
C Set if a carry is generated. Cleared otherwise.
Note: Normally the Z condition code bit is set via programming before
the start of an operation. This allows successful tests for zero results
upon completion of multiple-precision operations.
ADDX and SUBX are useful for processing number longer than 32bit.