plc chapter 3

t/f: usually a group of 8 bits is a byte, and a group of or more bytes is a word

true

The 2's complement form of a binary number is the binary number that results when: a.) all the 1's are changed to 0's. b.) all the 0's are changed to 1's. c.) 1 is added to the 1's complement. d.) both a and b

1 is added to the 1's complement

the decimal system has as its base

10

A memory that has a capacity of 700 sixteen-bit words can actually store __ bits of information.

11,200

the number 12 is: a.) 12 in any number system. b.) 12 in decimal. c.) 12 in binary. d.) all of the above.

12 in decimal

If a given memory unit consists of 1250 16-bit words, the memory capacity would be rated: a) 1250 bits b) 20,000 bits c) 3260 bits d) 156 bits

20,000 bits

for base 8 number system, the weight value associated with the 3rd digit would be: 16. 32. 64. 512.

64 (8^2)

PLCs work on_____ numbers in one form or another to represent various code quantities

binary

the number 127 could not be: a.) decimal. b.) hexadecimal. c.) octal. d.) binary.

binary

Each digit of a binary number is called a?

bit

All digital computing devices operate using the binary number system because: a.) most people are familiar with it. b.) large decimal numbers can be represented in a shorter form. c.) digital circuits can be easily distinguished between two voltage levels d.) all of the above.

digital circuits can be easily distinguished between two voltage levels

Two systems of parity are normally used: (a) ____and (b) ___ .

even and odd?

t/f: binary number systems use positive and negative symbols to represent the polarity of a number

false

t/f: the decimal system uses the number 9 at its base

false

t/f: to express a number in binary requires fewer digits than in the decimal system

false

ASCII code: 1.) is used with absolute encoders. 2.) is considered to be an error-minimizing code. 3.) includes letters as well as numbers. 4.) all of the above.

includes letters as well as numbers

in the sign but position, a 1 indicated a(n): a.) negative number. b.) positive number. c.) octal code. d.) hexadecimal code.

negative number

the main advantage of using the gray code is

only one digit changes as the number increases

a ___ bit is used to detect errors that may occur while a word is moved

parity

In any number system, the position of a digit that represents part of the number has a "weight" associated with its value. The place weights for binary: a.) start with 1 and are successive powers of 2. b.) increase by adding 2 for each place, starting with 0. c.) increase by adding 2 for each place, starting with 2. d.) start with 2 and double for each successive place.

start with 1 and are successive powers of 2

t/f the radix of a number system is the same as the bse

true

t/f: The base of a number system determines the total number of unique symbols used by that system.

true

t/f: The hexadecimal number system consists of 16 digits including the numbers 0 through 9 and letters A through F.

true

t/f: The octal number system consists of digits 0, 1, 2, 3, 4, 5, 6, and 7. There are no 8's or 9's.

true

t/f: all digital computing devices perform operations in binary

true

t/f: in any number system, the position of a digit that represents part if the number has a weighted value associated with it

true

t/f: in the gray code there is a max of one nit change between two consecutive numbers

true