Question

Assignment Consider the following program $s4,1648(Ss2) L1 w L2: addi $s4,$t3,-12 L3 beq $s4,St6,L5 $s4,8t6,L1 L1 L4: bne L5: Assuming the above program is loaded at 0XABCD5678, determine the machine code. Please state your answer in binary or hex. Make sure to state how many bits each field is - after all, a 5-bit 0 is not the same as a 6-bit 0

Answer 1

lw $s4,1648($s2)

Format : opcode(6-bit)     rs(5-bit)     rt(5-bit)            offset(16-bit)

              10011(lw)        10010($s2)    10100 ($s4)    0000 0110 0111 0000(1648)

Convert to hex:0X8E540670

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addi $s4,$t3,-12

Format: opcode(6-bit)               rt(5-bit)                rs(5-bit)         immediate(16-bit)

             001000(addi)            01011($t3)            10100($s4)     1111 1111 1111 0100(-12)

Hex: 0X2174FFF4

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beq $s4,$t6,L5

Format: Opcode(6-bit)           rs(5-bit)             rt(5-bit)          Offset

              000100(beq)          10100($s4)          01110($t6)      0000 0000 0000 0001(L5->After 1 instruction)

Hex: 0X128E0001

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bne $s4,$t6,L1

Format: Opcode(6-bit)           rs(5-bit)             rt(5-bit)            Offset

              000101(beq)          10100($s4)          01110($t6)      1111 1111 1111 1110(L1>2 instruction before , so become negative)

Hex: 0X168EFFFC

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j L1

Format: Opcode(6-bit)            Target(26-bit)

              000010(j)                 11 0011 0011 0101 0101 1001 1110(L1 address and right shift 2)

       Hex: 0X0B333559E