Homework 7

1. Show how each of the following numbers would be represented as 8-bit 2s-complement binary integers:

       
    93    -93    -64  
      
   

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2. Convert the following 8-bit 2s complement binary numbers to decimal:

       00011010
       11111011
       11101010
       10000000
   

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3. Given the declaration

              byt:    .byte     -1,0,-1,0
   

   Show what is in each register ($t0 through $t3) after the following code executes. Give your answer in hex.

               lb         $t0,byt
               lbu        $t1,byt
               lw         $t2,byt
               srl        $t3,$t2,8
               
   

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4. Show (using binary arithmetic) how the following sums would be computed in a 4-bit two's complement system. If an addition would generate an overflow, put a * next to the result. (Note: overflows occur when the sign is wrong!)

         3      4        5      -3       7        -4
       + 4    + 5     + -2    + -4     + 4        -6
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