Question

Write Two Different ARM Instructions That Will Force Bit 6 Of Low Byte Of Register RO To 0 , Without Changing Any Other Bits In The Low Byte Of RO. (Use Two-Operand Format, With Any Constants In Hexadecimal.)Write A Single ARM Instruction That Will Force Bits 5 And 2 In Register RO To 1 , Without Changing Any Other Bits In RO. (Use Two-Operand Format, With

Answer 1

To force bit 6 of the low byte of register RO to 0 without changing any other bits, use the AND operation. To force bits 5 and 2 in register RO to 1 without changing any other bits, use the OR operation.

Step-by-step explanation:

To force bit 6 of the low byte of register RO to 0 without changing any other bits, you can use the AND operation. The ARM instruction would be:

AND RO, RO, #BF

This instruction performs a bitwise AND between the value of register RO and the hexadecimal constant BF (which has a 0 in bit 6 and 1s in all other bits). This clears bit 6 in the result, effectively forcing it to 0.

To force bits 5 and 2 in register RO to 1 without changing any other bits, you can use the OR operation. The ARM instruction would be:

ORR RO, RO, #34

This instruction performs a bitwise OR between the value of register RO and the hexadecimal constant 34 (which has 1s in bits 5 and 2 and 0s in all other bits). This sets bits 5 and 2 in the result, effectively forcing them to 1.