SLAU144K December 2004 – August 2022 MSP430AFE221 , MSP430AFE222 , MSP430AFE223 , MSP430AFE231 , MSP430AFE232 , MSP430AFE233 , MSP430AFE251 , MSP430AFE252 , MSP430AFE253 , MSP430F2001 , MSP430F2002 , MSP430F2003 , MSP430F2011 , MSP430F2012 , MSP430F2013 , MSP430F2101 , MSP430F2111 , MSP430F2112 , MSP430F2121 , MSP430F2122 , MSP430F2131 , MSP430F2132 , MSP430F2132-EP , MSP430F2232 , MSP430F2234 , MSP430F2252 , MSP430F2252-Q1 , MSP430F2254 , MSP430F2272 , MSP430F2272-Q1 , MSP430F2274 , MSP430F2274-EP , MSP430F233 , MSP430F2330 , MSP430F235 , MSP430F2350 , MSP430F2370 , MSP430F2410 , MSP430F2416 , MSP430F2417 , MSP430F2418 , MSP430F2419 , MSP430F247 , MSP430F2471 , MSP430F248 , MSP430F2481 , MSP430F249 , MSP430F2491 , MSP430F2616 , MSP430F2617 , MSP430F2618 , MSP430F2619 , MSP430G2001 , MSP430G2101 , MSP430G2102 , MSP430G2111 , MSP430G2112 , MSP430G2121 , MSP430G2131 , MSP430G2132 , MSP430G2152 , MSP430G2153 , MSP430G2201 , MSP430G2201-Q1 , MSP430G2202 , MSP430G2203 , MSP430G2210 , MSP430G2211 , MSP430G2212 , MSP430G2213 , MSP430G2221 , MSP430G2230 , MSP430G2231 , MSP430G2231-Q1 , MSP430G2232 , MSP430G2233 , MSP430G2252 , MSP430G2253 , MSP430G2302 , MSP430G2303 , MSP430G2312 , MSP430G2313 , MSP430G2332 , MSP430G2333 , MSP430G2352 , MSP430G2353 , MSP430G2402 , MSP430G2403 , MSP430G2412 , MSP430G2413 , MSP430G2432 , MSP430G2433 , MSP430G2444 , MSP430G2452 , MSP430G2453 , MSP430G2513 , MSP430G2533 , MSP430G2544 , MSP430G2553 , MSP430G2744 , MSP430G2755 , MSP430G2855 , MSP430G2955 , MSP430TCH5E
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 one, two, three, or four bit positions as shown in Figure 4-46. The MSB retains its value (sign). RRAM operates equal to a signed division by 2/4/8/16. 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 two 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