Texas Instruments MSP430x1xx User Manual page 73

* DEC[.W] Decrement destination
* DEC.B Decrement destination
Syntax DEC
DEC.B
Operation dst − 1 −> dst
Emulation SUB
Emulation SUB.B
Description The destination operand is decremented by one. The original contents are
lost.
Status Bits N: Set if result is negative, reset if positive
Z: Set if dst contained 1, reset otherwise
C: Reset if dst contained 0, set otherwise
V: Set if an arithmetic overflow occurs, otherwise reset.
Mode Bits OSCOFF, CPUOFF, and GIE are not affected.
Example R10 is decremented by 1
DEC
; Move a block of 255 bytes from memory location starting with EDE to memory location starting with
;TONI. Tables should not overlap: start of destination address TONI must not be within the range EDE
; to EDE+0FEh
;
MOV
MOV
L$1 MOV.B
DEC
JNZ
; Do not transfer tables using the routine above with the overlap shown in Figure 3−12.
Figure 3−12. Decrement Overlap
dst or DEC.W
dst
#1,dst
#1,dst
Set if initial value of destination was 08000h, otherwise reset.
Set if initial value of destination was 080h, otherwise reset.
R10 ; Decrement R10
#EDE,R6
#255,R10
@R6+,TONI−EDE−1(R6)
R10
L$1
EDE
EDE+254
Instruction Set
dst
TONI
TONI+254
RISC 16−Bit CPU
3-37