Question

Question: WRITE A PROGRAM IN LC-3 ASSEMBLY LANGUAGE. DO NOT ... WRITE A PROGRAM IN LC-3 ASSEMBLY LANGUAGE. DO NOT USE PYTHON, JAVA, C or C++ or OTHERS. Your task is to write a program that counts the number of 1 bits of the value stored at location given by Datal. Your program should print the count (in hexadecimal, as it is easier) along with an appropriate heading. Test your program with the following values stored in Datal: a xFFFE b. x0002 C. XA55A d. xDEED exFACE Example: For input x0002, your program should print "Number of non-zero bits: x1", while for input XDEED, your program should print "Number of non-zero bits: xC".

Answer 1

PROGRAM:

   .ORIG x3000       ; Program strat at address x3000
   LD R0,Data1       ; Load the value of data1 into R0
   AND R1,R1,#0       ; Clear contents of R1
   ADD R1,R1,#1       ; Value to be compared to Data1
   AND R2,R2,#0       ; Clear contents of R2, Counter variable
   AND R3,R3,#0       ; Clear contents of R3, Result variable
loop
   ADD R2,R2,#1       ; Increment counter by 1
   AND R4,R4,#0       ; Clear contents of R4
   AND R4,R0,R1       ; R4=1, If LSB of R0 is 1
   BRP yes
no   ADD R1,R1,R1       ; Shift the contents of R1 to left
   BR next
yes   ADD R3,R3,#1       ; Increment result variable by 1
   BR no
next   AND R4,R4,#0       ; Clear contents of R4
   ADD R4,R2,#-16       ; Loop terminating condition
   BRN loop
end_loop
   LEA R0,prompt       ; Load the address of the string
   PUTS           ; Print the string
   ADD R4,R3,#-9       ; Check whether the result is >9
   BRp next1       ; if yes jump to label next1
   LD R1,ASCII       ; else, Load the value of ASCII into R1
   ADD R0,R3,R1       ; Move result to R0
   ST R0,result       ; Store the result
   BR exit           ; branch to label exit
next1   LD R1,char_val       ; Load the value of ASCII into R1
   ADD R0,R4,R1       ; Move result to R0
   ST R0,result       ; Store the result
exit   LEA R0,result       ; Load the address of the result
   PUTS           ; print the result
   HALT
Data1 .FILL x0002       ; data1 value
prompt .STRINGZ "Number of non-zero bits: x"
ASCII .FILL x30
char_val .FILL #65
result .BLKW #1
.END

Please refer to the following screenshot of the program for indentation of the code:

.ORIG X3000 ; Program strat at address x3000 LD RO,Data1 Load the value of data1 into RO AND R1, R1, #0 Clear contents of R1 ADD R1, R1, #1 Value to be compared to Data1 AND R2,R2, #9 Clear contents of R2, Counter variable AND R3, R3,# ; Clear contents of R3, Result variable 7 loop ADD R2, R2, #1 ; Increment counter by 1 AND R4,R4,#0 ; Clear contents of R4 AND R4,RO,R1 ; R4=1, If LSB of RO is 1 BRP yes 12 no ADD R1, R1, R1 ; Shift the contents of R1 to left 13 BR next yes ADD R3, R3,#1 ; Increment result variable by 1 15 BR no 16 next AND R4, R4,#6 ; Clear contents of R4 ADD R4, R2,#-16 ; Loop terminating condition BRN loop 19 end_loop LEA RO, prompt ; Load the address of the string PUTS ; Print the string ADD R4,R3,#-9 Check whether the result is >9 BRp next1 if yes jump to label next1 LD R1, ASCII else, Load the value of ASCII into R1 ADD RO,R3, R1 Move result to RO ST RO,result Store the result BR exit branch to label exit next1 LD R1,char_val Load the value of ASCII into R1 ADD RO,R4, R1 Move result to RO 30 SI RO,result Store the result 31 exit LEA RO,result Load the address of the result 32 PUTS ; print the result 33 HALT 34 Data1 .FILL x0002 ; datab value 35 prompt .STRINGZ "Number of non-zero bits: x" 36 ASCII .FILL X30 37 char_val .FILL #65 38 result .BLKW #1 39 .END

OUTPUTS:

When Data1 = x0002

Console Number of non-zero bits: x1 ----- Halting the processor -----

When Data1 = xDEED

Console Number of non-zero bits: xC ----- Halting the processor -----