Difference between revisions of "Assembly Language Division"

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Line 8: Line 8:
 
  8      BEQ END
 
  8      BEQ END
 
  9      SUB R2,R2,#1
 
  9      SUB R2,R2,#1
  10 END:OUT R2,4
+
  10     ADD R3,R0,R1
  11     HALT
+
11 END:OUT R2,4
 +
  12    OUT R3,4
 +
13     HALT
  
 
Line 1 & 2 will get the two numbers to divide.
 
Line 1 & 2 will get the two numbers to divide.
Line 27: Line 29:
 
Line 9 is reached if the compare was less than zero, so the last subtraction was one too far, so minus 1 from register 2.
 
Line 9 is reached if the compare was less than zero, so the last subtraction was one too far, so minus 1 from register 2.
  
Line 10 is the end label and will output the answer.
+
Line 10 is to workout the remainder.
  
Line 11 is the halt.
+
Line 11 is the end label and will output the answer.
 +
 
 +
Line 12 will output the remainder.
 +
 
 +
Line 13 is the halt.

Revision as of 12:54, 14 January 2019

1      INP R0,2
2      INP R1,2
3      MOV R2,#0
4 LOOP:SUB R0,R0,R1
5      ADD R2,R2,#1
6      CMP R0,#0
7      BGT LOOP
8      BEQ END
9      SUB R2,R2,#1
10     ADD R3,R0,R1
11 END:OUT R2,4
12     OUT R3,4
13     HALT

Line 1 & 2 will get the two numbers to divide.

Line 3 will clear register 2 and make sure its set to zero.

Line 4 is the loop label and it will subtract the second number from the first.

Line 5 will increment register 2 to count the number of subtractions we make.

Line 6 compares register 0 with zero.

Line 7 if the compare is greater than we still have subtractions to make.

Line 8 if the compare was equal, then we have completed and the number divides exactly.

Line 9 is reached if the compare was less than zero, so the last subtraction was one too far, so minus 1 from register 2.

Line 10 is to workout the remainder.

Line 11 is the end label and will output the answer.

Line 12 will output the remainder.

Line 13 is the halt.