Page 79 - Programmable Logic Controllers, Fifth Edition - Mobile version

18. Multiply the following binary numbers:
a. 110 × 110 19. Divide the following unsigned binary numbers:
a. 1010 ÷ 10
b. 010 × 101 b. 1100 ÷ 11
c. 101 × 11 c. 110110 ÷ 10

CHAPTER 3 PROBLEMS

1. The following binary PLC coded information is 4. Express the decimal number 18 in each of the fol-
to be programmed using the hexadecimal code. lowing number codes:
Convert each piece of binary information to the a. Binary
appropriate hexadecimal code for entry into the b. Octal
PLC from the keyboard. c. Hexadecimal
a. 0001 1111 d. BCD
b. 0010 0101 5. Add the binary number 110 to the negative binary
c. 0100 1110 number −101.
d. 0011 1001 6. Subtract 10112 − 1102.
2. The encoder circuit shown in Figure 3-19 is used 7. Multiply the following unsigned binary numbers:
to convert the decimal digits on the keyboard to a 101.1 and 10.11.
binary code. State the output status (HIGH/LOW)
of A-B-C-D when decimal number 8. Divide the following unsigned binary numbers:
a. 2 is pressed. 1110 by 10.
b. 5 is pressed. 9. State two instances that might call for the use of a
c. 7 is pressed. floating-point numbering system.
d. 8 is pressed. 10. What are the three basic components of a floating-
3. If the bits of a 16-bit word or register are numbered point number?
according to the octal numbering system, beginning
with 00, what consecutive numbers would be used
to represent each of the bits?

0
7 8 9 1
2
Decimal 3 Low A
number 4 5 6 High Low
pressed 4 Encoder High B
5 C
1 2 3 Low
6 D
7
0 8 Binary-coded
0100 output
9

4 input
High
Figure 3-19 Diagram for Problem 2.

60 Chapter 3 Number Systems and Codes

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