Jméno
SRR — shift right and roundoff
Popis
Shift contents of AC (except sign digit) and BR to the right n places. The positive integer n is treated modulo 32; digits shifted right out of BR15 are lost. (Shifting riht n places is equivalent to multiplying by 2-n.) Roundoff the result to 15 binary digits and store it in AC. Clear BR. Negative numbers are complemented before the shift and after the roundoff; hence, ones appear in the digit places made vacant by the shift of a negative number. Digit 6 (the 29 = 512 digit of the address) of the instruction srr n must be a zero to distinguish srr n from SRH n described below. The instruction srr 0 simply causes roundoff and clears BR. SAM is cleared. Roundof (in an srr0) may cause overflow with a consequent arithmetic check alarm. The time depends upon the size of n.
Odkazy
Podobné instrukce:
FIXME:whirlwind.isa.halt;.
