system digital
DESCRIPTION
System Digital. Enco der , Deco der , and Contoh Penerapanya. Encoder/Decoder Vocabulary. ENCODER- a digital circuit that produces a binary output code depending on which of its inputs are activated. . - PowerPoint PPT PresentationTRANSCRIPT
System Digital
Encoder, Decoder, andContoh Penerapanya
Encoder/Decoder Vocabulary
ENCODER- a digital circuit that produces a binary output code depending on which of its inputs are activated.
DECODER- a digital circuit that converts an input binary code into a single numeric output.
ENCODERS AND DECODERSA 0
A 1
A 2
A 3
A 4
A 5
A 6
A 7
ENCODER
O 0
O 1
O 2
A 0
A 1
A 2
O 0
O 1
O 2
O 3
O 4
O 5
O 6
O 7
DECODER
Hanya Satu masukan yang aktif pada satu waktuKeluaran berupa kode biner
Masukan berupa kode binerHanya satu keluaran yang aktif pada satu waktu
The truth table of 2-to-4 Decoder
2-to-4 Decoder
2-to-4 Decoder
The truth table of 3-to-8 DecoderA2 A1 A0 D0 D1 D2 D3 D4 D5 D6 D7
0 0 0 10 0 1 10 1 0 10 1 1 11 0 0 11 0 1 11 1 0 11 1 1 1
3-to-8 Decoder
3-to-8 Decoder with Enable
2-to-4 Decoder: NAND implementation
Decoder is enabled when E=0 and an output is active if it is 0
2-4 Decoder with 2-input and Enable
Decoder Expansion
Decoder expansion Combine two or more small decoders with enable
inputs to form a larger decoder
3-to-8-line decoder constructed from two 2-to-4-line decoders The MSB is connected to the enable inputs if A2=0, upper is enabled; if A2=1, lower is enabled.
Decoder Expansion
Combining two 2-4 decoders to form one 3-8 decoder using enable switch
The highest bit is used for the enables
THE 8421 BCD CODEBCD stands for Binary-Coded Decimal.
A BCD number is a four-bit binary group that represents one of the ten decimal digits 0 through 9.
Example:Decimal number 4926 4 9 2 6
8421 BCD coded number 0100 1001 0010 0110
ELECTRONIC ENCODER - DECIMAL TO BCD
0
Decimalto
BCDEncoder
BCD outputDecimal input 0 0 0 0
5
0 1 0 17
0 1 1 1
3
0 0 1 1
• Encoders are available in IC form.
• This encoder translates from decimal input to BCD output.
10 line to 4 line Encoder
ENCODER1248
DECIMAL BINARY (BCD)
9 5V
8 5V7 5V6 5V5 5V4 5V3 5V2 5V1 5V
74147I9I8I7I6I5I4I3I2I1
A0A1A2A3
10 line to 4 line Encoder
0
1
23
45
6
7
8
9
DECODER
BINARY (BCD)
DECIMAL
1 0V2 0V
4 0V
8 0V
74LS42
A3A2A1A0
9876543210
4 line to 10 line Decoder
BCD-to-7-SegmentDecoder/
Driver
DECODERS: BCD TO 7-SEGMENT DECODER/DRIVER
BCD input
0 0 0 0
Decimal outputLED
0 0 0 10 0 1 00 0 1 10 1 0 0
• Electronic decoders are available in IC form.• This decoder translates from BCD to decimal.• Decimals are shown on an 7-segment LED display.• This IC also drives the 7-segment LED display.
BCD-to-7-SegmentDecoder/
Driver
BCD input Decimal output0 0 1 1
?
Q #1- What is the decimal output from the decoder that appears on the 7-segment display?
Answer: 3
Q #2- What is the decimal output from the decoder that appears on the 7-segment display?
0 0 0 0
Answer: 0
Q #3- What is the decimal output from the decoder that appears on the 7-segment display?
1 0 0 1
Answer: 9
Q #4- What is the decimal output from the decoder that appears on the 7-segment display?
Answer: 7
0 1 1 1
Q #5- What is the decimal output from the decoder that appears on the 7-segment display?
Answer: 6
0 1 1 0
TEST
BCD-TO-SEVEN SEGMENT DECODER DRIVER
5V
abcdef g .
V+
74LS47A3A2A1A0
testRBI
gfedcba
RBO
TEST
A 0
A 1
A 2
A 3
A 4
A 5
A 6
A 7
ENCODER
O 0
O 1
O 2
O 3
A 8
A 9
INPUT O3 O2 O1 O0A1=1A4=1A6=1A8=1
TEST
A 0
A 1
A 2
O 0
O 1
O 2
O 3
O 4
O 5
O 6
O 7
DECODER
O 8
O 9
A 3
A3 A2 A1 A0 OUTPUT0 0 0 00 1 0 10 1 1 11 0 0 1
TESTANSWER THE FOLLOWING QUESTIONS WITH ONE OR
MORE OF THESE WORDS: MUX, DEMUX, ENCODER, DECODER.A. Has more inputs than outputs.
ENCODER, MUX
B. Uses select inputs.MUX, DEMUX
C. Can be used in parallel-to-serial conversion.MUX
D. Produces a binary code at its output.ENCODER
E. Only one of its outputs is activated at one time.DEMUX, DECODER
F. Used to route input signals to one of several outputs.MUX
G. Used to generate arbitrary logic functions. MUX, DEMUX
H. 3 line-to-8 line or binary to octal.DECODER
I. Data Selectors are alsoMUX.