Activities Manual For Programmable Logic Controllers
5th Edition
ISBN: 9781259682476
Author: Frank Petruzella
Publisher: Mcgraw-hill Higher Education (us)
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Chapter 13, Problem 28RQ
Explanation of Solution
Negative ways:
- Faulty wiring and
mechanical connections can interrupt or short the signals that are sent to and from the I/O modules. - This causes the sensors and actuators connected to the I/O modules to fail...
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Students have asked these similar questions
Consider the following sequential circuit:
CLOCK
a. Define the diagram circuit variables (5 pts)
b. Derive the Flip-Flop input equations) (5 pts)
c. Derive the circuit output equation (5 pts)
d. Derive the state table of the circuit (5 pts)
e. Derive the state diagram for this circuit (5 pts)
Clk
A
D
B
B'
CIK
Question 2 (25 pts)
A sequential circuit with two D flip-flops A and B, two inputs x and y, and one output z is
specified by the following next-state and output equations:
A(t + 1) = xy' + xB
B(t + 1) = xA + xB'
z = A
a. Draw the logic diagram of the circuit. (5 pts)
b. List the state table for the sequential circuit. (10 pts)
c. Draw the corresponding state diagram. (10 pts)
5. Word FrequencyWrite a program that reads the contents of a text file. The program should create a dictio-nary in which the keys are the individual words found in the file and the values are the number of times each word appears. For example, if the word “the” appears 128 times, the dictionary would contain an element with 'the' as the key and 128 as the value. The program should either display the frequency of each word or create a second file containing a list of each word and its frequency.
3.) File Encryption and DecryptionWrite a program that uses a dictionary to assign “codes” to each letter of the alphabet. For example:
codes = { ‘A’ : ‘%’, ‘a’ : ‘9’, ‘B’ : ‘@’, ‘b’ : ‘#’, etc . . .}Using this example, the letter A would be assigned the symbol %, the letter a would be assigned the number 9, the letter B would be assigned the symbol @, and so forth.
The program should open a specified text file, read its contents, then use the dictionary to write an encrypted version of the file’s contents to a second file. Each character in the second file should contain the code for the corresponding character in the first file.
Write a second program that opens an encrypted file and displays its decrypted contents on the screen.
Chapter 13 Solutions
Activities Manual For Programmable Logic Controllers
Ch. 13 - Prob. 1RQCh. 13 - Prob. 2RQCh. 13 - Prob. 3RQCh. 13 - List three potential noise-generating inductive...Ch. 13 - Prob. 5RQCh. 13 - Prob. 6RQCh. 13 - Prob. 7RQCh. 13 - Under what condition can a ground loop circuit be...Ch. 13 - Prob. 9RQCh. 13 - What operating state will cause an inductive load...
Ch. 13 - Prob. 11RQCh. 13 - Prob. 12RQCh. 13 - Prob. 13RQCh. 13 - Prob. 14RQCh. 13 - Prob. 15RQCh. 13 - List four uses for the data monitor function.Ch. 13 - Prob. 17RQCh. 13 - Prob. 18RQCh. 13 - Prob. 19RQCh. 13 - Prob. 20RQCh. 13 - Prob. 21RQCh. 13 - Prob. 22RQCh. 13 - Prob. 23RQCh. 13 - Prob. 24RQCh. 13 - Prob. 25RQCh. 13 - Prob. 26RQCh. 13 - Prob. 27RQCh. 13 - Prob. 28RQCh. 13 - Prob. 29RQCh. 13 - Prob. 30RQCh. 13 - Prob. 1PCh. 13 - A fuse is blown in an output module. Suggest two...Ch. 13 - Prob. 3PCh. 13 - Prob. 4PCh. 13 - Prob. 5PCh. 13 - Prob. 6PCh. 13 - A specific output is forced on, but the LED module...Ch. 13 - An electronic-based input sensor is wired to a...Ch. 13 - Prob. 9PCh. 13 - Prob. 11PCh. 13 - Prob. 12PCh. 13 - Prob. 13PCh. 13 - The program of Figure 13-39 is supposed to execute...
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