SLAU367P October 2012 – April 2020 MSP430FR5041 , MSP430FR5043 , MSP430FR50431 , MSP430FR5847 , MSP430FR58471 , MSP430FR5848 , MSP430FR5849 , MSP430FR5857 , MSP430FR5858 , MSP430FR5859 , MSP430FR5867 , MSP430FR58671 , MSP430FR5868 , MSP430FR5869 , MSP430FR5870 , MSP430FR5872 , MSP430FR58721 , MSP430FR5887 , MSP430FR5888 , MSP430FR5889 , MSP430FR58891 , MSP430FR5922 , MSP430FR59221 , MSP430FR5947 , MSP430FR59471 , MSP430FR5948 , MSP430FR5949 , MSP430FR5957 , MSP430FR5958 , MSP430FR5959 , MSP430FR5962 , MSP430FR5964 , MSP430FR5967 , MSP430FR5968 , MSP430FR5969 , MSP430FR5969-SP , MSP430FR59691 , MSP430FR5970 , MSP430FR5972 , MSP430FR59721 , MSP430FR5986 , MSP430FR5987 , MSP430FR5988 , MSP430FR5989 , MSP430FR5989-EP , MSP430FR59891 , MSP430FR5992 , MSP430FR5994 , MSP430FR59941 , MSP430FR6005 , MSP430FR6007 , MSP430FR6035 , MSP430FR6037 , MSP430FR60371 , MSP430FR6041 , MSP430FR6043 , MSP430FR60431 , MSP430FR6045 , MSP430FR6047 , MSP430FR60471 , MSP430FR6820 , MSP430FR6822 , MSP430FR68221 , MSP430FR6870 , MSP430FR6872 , MSP430FR68721 , MSP430FR6877 , MSP430FR6879 , MSP430FR68791 , MSP430FR6887 , MSP430FR6888 , MSP430FR6889 , MSP430FR68891 , MSP430FR6920 , MSP430FR6922 , MSP430FR69221 , MSP430FR6927 , MSP430FR69271 , MSP430FR6928 , MSP430FR6970 , MSP430FR6972 , MSP430FR69721 , MSP430FR6977 , MSP430FR6979 , MSP430FR69791 , MSP430FR6987 , MSP430FR6988 , MSP430FR6989 , MSP430FR69891
4.6.3.25 RRAM
| RRAM.A | Rotate right arithmetically the 20-bit CPU register content | ||
| RRAM.[W] | Rotate right arithmetically the 16-bit CPU register content | ||
| Syntax | RRAM.A #n,Rdst | 1 ≤ n ≤ 4 | |
| RRAM.W #n,Rdst or RRAM #n,Rdst | 1 ≤ n ≤ 4 | ||
| Operation | MSB → MSB → MSB–1 ... LSB+1 → LSB → C | ||
| Description | The destination operand is shifted right arithmetically by 1, 2, 3, or 4 bit positions as shown in Figure 4-47. The MSB retains its value (sign). RRAM operates equal to a signed division by 2, 4, 8, or 16. The MSB is retained and shifted into MSB-1. The LSB+1 is shifted into the LSB, and the LSB is shifted into the carry bit C. The word instruction RRAM.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 signed 20-bit number in R5 is shifted arithmetically right 2 positions. | ||
RRAM.A #2,R5 ; R5/4 -> R5
| Example | The signed 20-bit value in R15 is multiplied by 0.75. (0.5 + 0.25) × R15. | ||
PUSHM.A #1,R15 ; Save extended R15 on stack
RRAM.A #1,R15 ; R15 y 0.5 -> R15
ADDX.A @SP+,R15 ; R15 y 0.5 + R15 = 1.5 y R15 -> R15
RRAM.A #1,R15 ; (1.5 y R15) y 0.5 = 0.75 y R15 -> R15
Figure 4-47 Rotate Right Arithmetically RRAM[.W] and RRAM.A