Extended Instructions
4-145
16-Bit MSP430X CPU
RRUM.A
Rotate Right Unsigned the 20-bit CPU register content
RRUM[.W]
Rotate Right Unsigned the 16-bit CPU register content
Syntax
RRUM.A
#n,Rdst
1
≤
n
≤
4
RRUM.W
#n,Rdst
or RRUM #n,Rdst
1
≤
n
≤
4
Operation
0
→
MSB
→
MSB
-
1 .
→
... LSB+1
→
LSB
→
C
Description
The destination operand is shifted right by one, two, three, or four bit positions
as shown in Figure 4−53. Zero is shifted into the MSB, the LSB is shifted into
the carry bit. RRUM works like an unsigned division by 2, 4, 8, or 16. The word
instruction RRUM.W clears the bits Rdst.19:16.
Note : This instruction does not use the extension word.
Status Bits
N:
Set if result is negative
.A: Rdst.19 = 1, reset if Rdst.19 = 0
.W: Rdst.15 = 1, reset if Rdst.15 = 0
Z:
Set if result is zero, reset otherwise
C:
Loaded from the LSB (n = 1), LSB+1 (n = 2), LSB+2 (n = 3) or LSB+3
(n = 4)
V: Reset
Mode Bits
OSCOFF, CPUOFF, and GIE are not affected.
Example
The unsigned address-word in R5 is divided by 16.
RRUM.A
#4,R5
; R5 = R5
»
4. R5/16
Example
The word in R6 is shifted right by one bit. The MSB R6.15 is loaded with 0.
RRUM.W
#1,R6
; R6 = R6/2. R6.19:15 = 0
Figure 4−53. Rotate Right Unsigned RRUM[.W] and RRUM.A
C
19
0
MSB
0000
15
LSB
C
19
0
MSB
LSB
0
0
16
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 ...