Question

Is there a sequence of LC-3 instructions that will cause the condition codes at the end of the sequence to be N=0, Z=1, P=1? Explain.

Answer 1

Yes, there is a sequence of LC-3 instructions that will cause the condition codes to be N=0, Z=1, P=1 at the end.

An example is performing a bitwise AND operation on a value in a register with itself, adding -1 to the result, and branching based on the result.

Step-by-step explanation:

The LC-3 instruction set implements fifteen types of instructions, with a sixteenth opcode reserved for later use.

The architecture is a load-store architecture; values in memory must be brought into the register file before they can be operated upon.

There is a sequence of LC-3 instructions that will cause the condition codes at the end of the sequence to be N=0, Z=1, P=1.

Here's an example:

1. AND R0, R0, #0
2. ADD R0, R0, #-1
3. BRzp Loop

This sequence of instructions performs a bitwise AND operation on the value in R0 with itself, then adds -1 to the result.

Finally, it branches back to the 'Loop' label if the result is zero, positive, or negative, which sets the condition codes N=0, Z=1, P=1.