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
SXT | Extend sign | ||
Syntax |
SXT dst | ||
Operation | dst.7 → dst.15:8, dst.7 → dst.19:8 (register mode) | ||
Description | Register mode: the sign of the low byte of the operand is extended into the bits Rdst.19:8. Rdst.7 = 0: Rdst.19:8 = 000h afterwards Rdst.7 = 1: Rdst.19:8 = FFFh afterwards Other modes: the sign of the low byte of the operand is extended into the high byte. dst.7 = 0: high byte = 00h afterwards dst.7 = 1: high byte = FFh afterwards | ||
Status Bits | N: | Set if result is negative, reset otherwise | |
Z: | Set if result is zero, reset otherwise | ||
C: | Set if result is not zero, reset otherwise (C = .not.Z) | ||
V: | Reset | ||
Mode Bits | OSCOFF, CPUOFF, and GIE are not affected. | ||
Example | The signed 8-bit data in EDE (lower 64KB) is sign extended and added to the 16-bit signed data in R7. |
MOV.B &EDE,R5 ; EDE -> R5. 00XXh
SXT R5 ; Sign extend low byte to R5.19:8
ADD R5,R7 ; Add signed 16-bit values
Example | The signed 8-bit data in EDE (PC +32 K) is sign extended and added to the 20-bit data in R7. |
MOV.B EDE,R5 ; EDE -> R5. 00XXh
SXT R5 ; Sign extend low byte to R5.19:8
ADDA R5,R7 ; Add signed 20-bit values