Instruction Set
3-62
RISC 16-Bit CPU
* SBC[.W]
Subtract source and borrow/.NOT. carry from destination
* SBC.B
Subtract source and borrow/.NOT. carry from destination
Syntax
SBC
dst or
SBC.W
dst
SBC.B
dst
Operation
dst + C −> dst
dst + 0FFh + C −> dst
Emulation
SUBC
#0,dst
SUBC.B
#0,dst
Description
The carry bit (C) is added to the destination operand minus one. The previous
contents of the destination are lost.
Status Bits
N: Set if result is negative, reset if positive
Z: Set if result is zero, reset otherwise
C: Set if there is a carry from the MSB of the result, reset otherwise.
Set to 1 if no borrow, reset if borrow.
V: Set if an arithmetic overflow occurs, reset otherwise.
Mode Bits
OSCOFF, CPUOFF, and GIE are not affected.
Example
The 16-bit counter pointed to by R13 is subtracted from a 32-bit counter
pointed to by R12.
SUB
@R13,0(R12)
; Subtract LSDs
SBC
2(R12)
; Subtract carry from MSD
Example
The 8-bit counter pointed to by R13 is subtracted from a 16-bit counter pointed
to by R12.
SUB.B
@R13,0(R12)
; Subtract LSDs
SBC.B
1(R12)
; Subtract carry from MSD
Note:
Borrow Implementation.
The borrow is treated as a .NOT. carry :
Borrow
Carry bit
Yes
0
No
1
Summary of Contents for MSP430x4xx Family
Page 1: ...MSP430x4xx Family 2007 Mixed Signal Products User s Guide SLAU056G ...
Page 2: ......
Page 6: ...vi ...
Page 114: ...3 76 RISC 16 Bit CPU ...
Page 304: ...5 20 FLL Clock Module ...
Page 340: ...7 8 Supply Voltage Supervisor ...
Page 348: ...8 8 16 Bit Hardware Multiplier ...
Page 372: ...9 24 32 Bit Hardware Multiplier ...
Page 400: ...10 28 DMA Controller ...
Page 428: ...13 10 Basic Timer1 ...
Page 466: ...15 24 Timer_A ...
Page 522: ...17 30 USART Peripheral Interface UART Mode ...
Page 544: ...18 22 USART Peripheral Interface SPI Mode ...
Page 672: ...23 12 Comparator_A ...
Page 692: ...24 20 LCD Controller ...
Page 746: ...26 28 ADC12 ...