Activities Manual For Programmable Logic Controllers
5th Edition
ISBN: 9781259682476
Author: Frank Petruzella
Publisher: Mcgraw-hill Higher Education (us)
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Expert Solution & Answer
Chapter 2, Problem 24RQ
Explanation of Solution
Comparison on discrete and analog I/O modules:
| Discrete I/O modules | Analog I/O modules |
| In discrete I/O modules, the output value may be either ON or OFF. | In analog modules, the output value may be any continuous value such as 0 to 440mA or 0 to 20 V within its specific range. |
| It allows connecting only ON/OFF devices... |
Expert Solution & Answer
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Students have asked these similar questions
1234
3. Which line prevents compiler optimization? Circle one: 1234
Suggested solution:
Store strlen(str) in a variable before the if statement.
⚫ Remove the if statement.
Replace index 0 && index < strlen(str)) {
5 }
}
=
str [index] = val;
Character Hex value | Character Hex value Character Hex value
'A'
0x41
'J'
Ox4a
'S'
0x53
'B'
0x42
'K'
0x4b
"T"
0x54
0x43
'L'
Ox4c
'U'
0x55
0x44
'M'
0x4d
'V'
0x56
0x45
'N'
Ox4e
'W'
0x57
0x46
'0'
Ox4f
'X'
0x58
0x47
'P'
0x50
'Y'
0x59
0x48
'Q'
0x51
'Z'
Ox5a
'T'
0x49
'R'
0x52
'\0'
0x00
Now consider what happens on a Linux/x86 machine when callfoo calls foo with
the input string "ZYXWVUTSRQPONMLKJIHGFEDCBA".
A. On the left draw the state of the stack just before the execution of the instruction
at address Ox40053a; make sure to show the frames for callfoo and foo and
the exact return address, in Hex at the bottom of the callfoo frame.
Then, on the right, draw the state of the stack just after the instruction got
executed; make sure to show where the string "ZYXWVUTSRQPONMLKJIHGFEDCBA"
is placed and what part, if any, of the above return address has been overwritten.
B. Immediately after the ret instruction at address 0x400543 executes, what is
the value of the program counter register %rip?…
1 typedef struct node* {
2
struct node* next;
3
char* key;
4
char* val;
5} node_t;
6
7 char* find_node (node_t* node, char* key_to_find) {
while(strcmp (node->key, key_to_find ) != 0 ) {
node = node->next;
8
9
10
}
11
return node->val;
12 }
Chapter 2 Solutions
Activities Manual For Programmable Logic Controllers
Ch. 2 - Prob. 1RQCh. 2 - What is the function of a PLC output interface...Ch. 2 - Prob. 3RQCh. 2 - Prob. 4RQCh. 2 - Prob. 5RQCh. 2 - Prob. 6RQCh. 2 - Prob. 7RQCh. 2 - Prob. 8RQCh. 2 - Prob. 9RQCh. 2 - Prob. 10RQ
Ch. 2 - Prob. 11RQCh. 2 - What are the advantage and the disadvantage of...Ch. 2 - With reference to PLC discrete input modules: a....Ch. 2 - Prob. 14RQCh. 2 - Explain the function of the backplane of a PLC...Ch. 2 - Prob. 16RQCh. 2 - Prob. 17RQCh. 2 - Prob. 18RQCh. 2 - What electronic element can be used as the...Ch. 2 - With reference to discrete output module current...Ch. 2 - What electronic element can be used as the...Ch. 2 - Prob. 22RQCh. 2 - Prob. 23RQCh. 2 - Prob. 24RQCh. 2 - Prob. 25RQCh. 2 - Prob. 26RQCh. 2 - Prob. 27RQCh. 2 - Prob. 28RQCh. 2 - Prob. 29RQCh. 2 - Explain the difference between a unipolar and...Ch. 2 - Prob. 31RQCh. 2 - In what two ways can the loop power for current...Ch. 2 - Prob. 33RQCh. 2 - Prob. 34RQCh. 2 - Prob. 35RQCh. 2 - Write a short explanation for each of the...Ch. 2 - Write a short explanation for each of the...Ch. 2 - Prob. 38RQCh. 2 - Prob. 39RQCh. 2 - Prob. 40RQCh. 2 - Prob. 41RQCh. 2 - Prob. 42RQCh. 2 - Prob. 43RQCh. 2 - Prob. 44RQCh. 2 - Prob. 45RQCh. 2 - Prob. 46RQCh. 2 - Prob. 47RQCh. 2 - What information is normally stored in the ROM...Ch. 2 - Prob. 49RQCh. 2 - Prob. 50RQCh. 2 - Prob. 51RQCh. 2 - Prob. 52RQCh. 2 - Prob. 53RQCh. 2 - Prob. 54RQCh. 2 - Prob. 55RQCh. 2 - Prob. 56RQCh. 2 - Prob. 57RQCh. 2 - Prob. 58RQCh. 2 - Prob. 59RQCh. 2 - Prob. 60RQCh. 2 - What is the function of a transducer?Ch. 2 - Prob. 62RQCh. 2 - Prob. 1PCh. 2 - Assume a thermocouple, which supplies the input to...Ch. 2 - With reference to I/O module specifications: a. If...Ch. 2 - Prob. 4PCh. 2 - Prob. 5PCh. 2 - Prob. 6P
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