Question

This program is supposed to set RO-1 if there's a 5 in one of ten memory locations, starting at x3100 Else, it should set RO to 0. R0 1, R1-5, R3 10 R4x3100, R2 MIR4] No R4 R41 R3 R3-1 R2 MIR4] Yes HALT Output the adress of the 5 to the console. The console should display A five found at x3107 (if the five is at x3107) If no five found, display No five found

   write a LC-3 program

Answer 1

1.  First we set R0=1, R1=-5 ,r3=10, R4=x3100 , R2=M[R4]
then we check if there is value 5 at memory location R4 if yes so we will halt
if no then we will do this calculations 
R4++
R3--
R2=M[R4]
2. Then we check if there is value zero in R3 then we will set R3 to 0 and halt else we will set value of R2 again to 5
in ist iteration when condition shown in line is checked this will match and we assume that the condition is false so we will increment R4 like x3101 
decrement R3 as 9 and save the value of memory to r2 AND CHECK THAT IF ITS FALSE THEN WE WILL REPEAT STEP2 

3.Then we check if there is value zero in R3 then we will set R3 to 0 and halt else we will set value of R2 again to VALUE SET BY MEMORY in 2ND iteration when condition shown in line is checked this will match and we assume that the condition is false so we will increment R4 like x3102 
decrement R3 as 8 and save the value of memory to r2 AND CHECK THAT IF ITS FALSE THEN WE WILL REPEAT STEP2 

4.Then we check if there is value zero in R then we will set R3 to 0 and halt else we will set value of R2 again to VALUE SET BY MEMORY
in 3RD iteration when condition shown in line is checked this will match and we assume that the condition is false so we will increment R4 like x3103 
decrement R3 as 6 and save the value of memory to r2 AND CHECK THAT IF ITS FALSE THEN WE WILL REPEAT STEP2 

5. Then we check if there is value zero in R3 then we will set R3 to 0 and halt else we will set value of R2 again to VALUE SET BY MEMORY
in 4TH iteration when condition shown in line is checked this will match and we assume that the condition is false so we will increment R4 like x3104 
decrement R3 as 5 and save the value of memory to r2 and check that if it's FALSE then we will REPEAT STEP2 

So here is 4TH iteration and we found 5 but now the condition will FALSE and we will HALT the program and statement will be 5 cantc find because our scenario is to find it at X3107 A
and its at X3104.