If R1 contains x0000 and R2 contains xFFFF then what are the condition code values after the following instruction is executed?0001 011 001 0 00 010A.) N is B.) Z is C.) P is D.) Is it possible for more than one condition code in LC-3 to be set to 1 at the same time?
Question
If R1 contains x0000 and R2 contains xFFFF then what are the condition code values after the following instruction is executed?0001 011 001 0 00 010A.) N is B.) Z is C.) P is D.) Is it possible for more than one condition code in LC-3 to be set to 1 at the same time?
Solution
The instruction given is an ADD instruction in LC-3 assembly language. The operation is R1 + R2. Given that R1 contains x0000 and R2 contains xFFFF, the result of the operation is xFFFF.
The condition codes are set based on the result of the operation:
A.) N (negative) is set if the result is negative. In this case, the result xFFFF is considered negative in two's complement representation, so N is 1.
B.) Z (zero) is set if the result is zero. In this case, the result is not zero, so Z is 0.
C.) P (positive) is set if the result is positive. In this case, the result is not positive, so P is 0.
D.) In LC-3, only one condition code can be set at a time. The condition codes are mutually exclusive. So, it is not possible for more than one condition code to be set to 1 at the same time.
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