
Programmable Logic Controllers
5th Edition
ISBN: 9780073373843
Author: Frank D. Petruzella
Publisher: McGraw-Hill Education
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Chapter 15.2, Problem 9RQ
Program Plan Intro
ControlLogix (CLX) system:
- It is composed of a stand-alone controller and input or output modules will be in a single chassis.
- It is a well distributed system because it is made up of numerous chassis and networks functioning together.
- The processor of CLX offers a flexible memory structure.
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Consider the following assembly code for a C for loop:
movl $0, %eax
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.L2
.L3:
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$1, %rdi
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.L2:
cmpq
%rsi, %rdi
jl
.L3
addq
ret
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Based on the assembly code above, fill in the blanks below in its corresponding C
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argument of a function. (Note: you may only use the symbolic variables x, y, and
result in your expressions below do not use register names.)
long loop (long x, long y)
{
long result;
}
for (
}
return result;
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In each of the following C code snippets, there are issues that can prevent the compiler
from applying certain optimizations. For each snippet:
Circle the line number that contains compiler optimization blocker.
⚫ Select the best modification to improve optimization.
1. Which line prevents compiler optimization? Circle one: 2 3 4 5 6
Suggested solution:
⚫ Remove printf or move it outside the loop.
Remove the loop.
• Replace arr[i] with a constant value.
1 int sum (int *arr, int n) {
2
int s = 0;
3
for (int i
=
0; i < n; i++) {
4
5
6
}
7
8 }
s = arr[i];
printf("%d\n", s);
return s;
234206
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Move or eliminate do_extra_work() if it's not necessary inside the loop.
Remove the loop (but what about scaling?).
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1 void scale (int *arr, int n, int factor) {
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sub
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Chapter 15 Solutions
Programmable Logic Controllers
Ch. 15.1 - Prob. 1RQCh. 15.1 - Prob. 2RQCh. 15.1 - Prob. 3RQCh. 15.1 - Prob. 4RQCh. 15.1 - Prob. 5RQCh. 15.1 - Prob. 6RQCh. 15.1 - Prob. 7RQCh. 15.1 - Prob. 8RQCh. 15.1 - Prob. 9RQCh. 15.1 - Prob. 10RQ
Ch. 15.1 - Prob. 11RQCh. 15.1 - Compare the accessibility of program scope and...Ch. 15.1 - Prob. 13RQCh. 15.1 - What is the difference between a produced tag and...Ch. 15.1 - Prob. 15RQCh. 15.1 - State the data type used for each of the...Ch. 15.1 - Describe the make-up of a predefined structure.Ch. 15.1 - Describe the make-up of a module-defined...Ch. 15.1 - Describe the make-up of a user-defined structure.Ch. 15.1 - Prob. 20RQCh. 15.1 - Prob. 21RQCh. 15.1 - Prob. 22RQCh. 15.1 - Prob. 23RQCh. 15.2 - Prob. 1RQCh. 15.2 - Prob. 2RQCh. 15.2 - Prob. 3RQCh. 15.2 - Prob. 4RQCh. 15.2 - Prob. 5RQCh. 15.2 - Prob. 6RQCh. 15.2 - Prob. 7RQCh. 15.2 - Prob. 8RQCh. 15.2 - Prob. 9RQCh. 15.2 - Prob. 10RQCh. 15.2 - Prob. 11RQCh. 15.2 - Extend control of the original ControlLogix...Ch. 15.2 - Prob. 3PCh. 15.3 - Prob. 1RQCh. 15.3 - Prob. 2RQCh. 15.3 - Prob. 3RQCh. 15.3 - Prob. 4RQCh. 15.3 - Prob. 5RQCh. 15.3 - Prob. 6RQCh. 15.3 - Prob. 7RQCh. 15.3 - Prob. 8RQCh. 15.3 - Prob. 9RQCh. 15.3 - Prob. 10RQCh. 15.3 - Prob. 11RQCh. 15.3 - Prob. 12RQCh. 15.3 - Modify the original CLX ten-second TON timer...Ch. 15.3 - Prob. 2PCh. 15.3 - Prob. 3PCh. 15.3 - Prob. 4PCh. 15.3 - Prob. 5PCh. 15.3 - Prob. 6PCh. 15.4 - Prob. 1RQCh. 15.4 - Prob. 2RQCh. 15.4 - Prob. 3RQCh. 15.4 - Prob. 4RQCh. 15.4 - Prob. 5RQCh. 15.4 - Prob. 6RQCh. 15.4 - Prob. 7RQCh. 15.4 - Prob. 1PCh. 15.4 - Prob. 2PCh. 15.5 - Prob. 1RQCh. 15.5 - Prob. 2RQCh. 15.5 - Prob. 3RQCh. 15.5 - Prob. 4RQCh. 15.5 - Prob. 5RQCh. 15.5 - Construct a ControlLogix ladder rung with compare...Ch. 15.5 - Prob. 2PCh. 15.5 - A single pole switch is used in place of the two...Ch. 15.6 - Prob. 1RQCh. 15.6 - Name the four basic elements of an FBD.Ch. 15.6 - Prob. 3RQCh. 15.6 - Prob. 4RQCh. 15.6 - Prob. 5RQCh. 15.6 - Prob. 6RQCh. 15.6 - Prob. 7RQCh. 15.6 - Prob. 8RQCh. 15.6 - Prob. 9RQCh. 15.6 - Prob. 10RQCh. 15.6 - Prob. 11RQCh. 15.6 - How is a function block feedback loop created?Ch. 15.6 - Prob. 13RQCh. 15.6 - Prob. 14RQCh. 15.6 - Prob. 1PCh. 15.6 - Prob. 2PCh. 15.6 - Prob. 3PCh. 15.6 - Prob. 4PCh. 15.6 - Prob. 5P
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