Popis
Multiply the contetns of AC and BR by 2 often enough to make the positive magnitude of the product equal to or greater than 1/2. Leave the finale product in AC and BR. Store the number of multiplications in AR and in last 11 digit places of memory[x], the first 5 digits being undisturbed in memory[x]. If all the digits in BR are zero and AC contains ±0, the instruction sf x leaves AC and BR undisturbed and stores the number 33 times 2-15 in AR and in the last 11 digit positions of memory[x]. Negative numbers are complemented in AC before and after the multiplication (by shifting); hence ones appear in the digit places made vacant by the shift. SAM is cleared. The time varies according to the number of 0's between the binary point and first 1 in magnitude of binary fraction represented by the number AC and BR. The minimum time of 30 μs occurs when |AC + BR| ≥ 1/2; the maximum time of 78 μs occurs when |AC+BR| = 0.
Odkazy
Podobné instrukce:
FIXME:whirlwind.isa.halt;.
