COMPUTER SCIENCE ILLUMINATED
7th Edition
ISBN: 9781284208047
Author: Dale
Publisher: JONES+BART
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Chapter 6, Problem 42E
Explanation of Solution
Given code:
The given program is as follows:
BR main
sum: .WORD 0x0000
num1: .BLOCK 1
num2: .BLOCK 1
num3: .BLOCK 1
main: LDWA sum,d
DECI num1,d
DECI num2,d
DECI num3,d
ADDA num3,d
ADDA num2,d
ADDA num1,d
STWA sum,d
DECO sum,d
STOP
.END
Explanation:
- The above code is to get the input for the variables “num1”, “num2”, and “num3” from the user.
- Then, the sum of three numbers is calculated and the total value on the screen is displayed.
- The highlighted lines in the code shows that the storage setup for the input variables “num1”, “num2”, and “num3” is only 1 byte.
- If the size of the input value is greater than 1 byte, then the given code results in a wrong output.
- As per the test plan used in this chapter, the largest input value is 32767; it needs two bytes of memory to store the value.
- Therefore, wrong results can be avoided by declaring the variables with two bytes.
Corrected code:
The bug in the given code is rectified and the corrected code is as follows:
BR main
sum: ...
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Chapter 6 Solutions
COMPUTER SCIENCE ILLUMINATED
Ch. 6 - Prob. 1ECh. 6 - Prob. 2ECh. 6 - Prob. 3ECh. 6 - Prob. 4ECh. 6 - Prob. 5ECh. 6 - Prob. 6ECh. 6 - Prob. 7ECh. 6 - Prob. 8ECh. 6 - Prob. 9ECh. 6 - Prob. 10E
Ch. 6 - Prob. 11ECh. 6 - Prob. 12ECh. 6 - Prob. 13ECh. 6 - Prob. 14ECh. 6 - Prob. 15ECh. 6 - Prob. 16ECh. 6 - Prob. 17ECh. 6 - Prob. 18ECh. 6 - Prob. 19ECh. 6 - Prob. 20ECh. 6 - Prob. 21ECh. 6 - Prob. 22ECh. 6 - Prob. 23ECh. 6 - Prob. 24ECh. 6 - Prob. 25ECh. 6 - Prob. 26ECh. 6 - Prob. 27ECh. 6 - Prob. 28ECh. 6 - Prob. 29ECh. 6 - Prob. 30ECh. 6 - Prob. 31ECh. 6 - Prob. 32ECh. 6 - Prob. 33ECh. 6 - Prob. 34ECh. 6 - Prob. 35ECh. 6 - Prob. 36ECh. 6 - Prob. 37ECh. 6 - Prob. 38ECh. 6 - Prob. 39ECh. 6 - Prob. 40ECh. 6 - Prob. 41ECh. 6 - Prob. 42ECh. 6 - Prob. 44ECh. 6 - Prob. 45ECh. 6 - Prob. 46ECh. 6 - Prob. 47ECh. 6 - Prob. 48ECh. 6 - Prob. 49ECh. 6 - Prob. 50ECh. 6 - Prob. 51ECh. 6 - Prob. 52ECh. 6 - Prob. 53ECh. 6 - Prob. 54ECh. 6 - Prob. 55ECh. 6 - Prob. 56ECh. 6 - Prob. 57ECh. 6 - Prob. 58ECh. 6 - Prob. 59ECh. 6 - Prob. 60ECh. 6 - Prob. 1TQCh. 6 - Prob. 2TQCh. 6 - Prob. 3TQCh. 6 - Prob. 4TQ
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