Instruction Set Description
163
SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
CPUX
4.6.2.3
ADDC
ADDC[.W]
Add source word and carry to destination word
ADDC.B
Add source byte and carry to destination byte
Syntax
ADDC src,dst
or
ADDC.W src,dst
ADDC.B src,dst
Operation
src + dst + C
→
dst
Description
The source operand and the carry bit C are added to the destination operand. The
previous content of the destination is lost.
Status Bits
N:
Set if result is negative (MSB = 1), reset if positive (MSB = 0)
Z:
Set if result is zero, reset otherwise
C:
Set if there is a carry from the MSB of the result, reset otherwise
V:
Set if the result of 2 positive operands is negative, or if the result of 2 negative
numbers is positive, reset otherwise
Mode Bits
OSCOFF, CPUOFF, and GIE are not affected.
Example
Constant value 15 and the carry of the previous instruction are added to the 16-bit
counter CNTR located in lower 64 K.
ADDC.W
#15,&CNTR
; Add 15 + C to 16-bit CNTR
Example
A table word pointed to by R5 (20-bit address) and the carry C are added to R6. The
jump to label TONI is performed on a carry. R6.19:16 = 0
ADDC.W
@R5,R6
; Add table word + C to R6
JC
TONI
; Jump if carry
...
; No carry
Example
A table byte pointed to by R5 (20-bit address) and the carry bit C are added to R6. The
jump to label TONI is performed if no carry occurs. The table pointer is auto-incremented
by 1. R6.19:8 = 0
ADDC.B
@R5+,R6
; Add table byte + C to R6. R5 + 1
JNC
TONI
; Jump if no carry
...
; Carry occurred