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section 7 - Index of

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ASR Arithmetic Shift Accumulator Right ASROperation:d 7 I-----tl~~ I----.....55 47 23 0~~ I C (parallel move)Assembler Syntax:ASR 0 (parallel move)Description: Arithmetically shift the destination operand 0 one bit to the right and storethe result in the destination accumulator. The LS bit <strong>of</strong> 0 prior to instruction execution isshifted into the carry bit C, and the MS bit <strong>of</strong> 0 is held constant.Example:ASRB X:-(R3),R3 ;divide B by 2, update R3, load R3B L-IBefore Execution_--=$_A8_:A_8_64_20_:A_864_21_---lAfter ExecutionBI ......__$_D4_:5_43_2_10_:54_3_21_0_----'SRI ......_____$0_30_0_---' SR I ......_______ $_0_32_9_----'Explanation <strong>of</strong> Example: Prior to execution, the 56-bit B accumulator contains thevalue $A8:A86420:A86421. The execution <strong>of</strong> the ASR B instruction shifts the 56-bit valuein the B accumulator one bit to the right and stores the result back in the B accumulator.

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