Aula 2 - Paridade e Algebra de Boole.SEL405 - Iris.sel.eesc.sc.usp.br
Aula 2 - Paridade e Algebra de Boole.SEL405 - Iris.sel.eesc.sc.usp.br
Aula 2 - Paridade e Algebra de Boole.SEL405 - Iris.sel.eesc.sc.usp.br
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
<strong>Aula</strong> 2<<strong>br</strong> />
<strong>Parida<strong>de</strong></strong> e Álge<strong>br</strong>a <strong>de</strong> <strong>Boole</strong><<strong>br</strong> />
SEL 0405 – Introdução aos<<strong>br</strong> />
Sistemas Digitais<<strong>br</strong> />
Prof. Dr. Marcelo Andra<strong>de</strong> da Costa Vieira
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
Transmissão <strong>de</strong> Dados Digitais<<strong>br</strong> />
l Menos sujeitos à ruídos do que sistemas<<strong>br</strong> />
analógicos;<<strong>br</strong> />
l Detecção <strong>de</strong> erros por parida<strong>de</strong>.
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
BIT DE PARIDADE<<strong>br</strong> />
l Utilizada em transmissão para minimizar<<strong>br</strong> />
erros;<<strong>br</strong> />
l Bit extra anexado ao conjunto <strong>de</strong> bits para<<strong>br</strong> />
informar a sua parida<strong>de</strong>;<<strong>br</strong> />
l O bit <strong>de</strong> parida<strong>de</strong> po<strong>de</strong> ser 0 ou 1,<<strong>br</strong> />
<strong>de</strong>pen<strong>de</strong>ndo do número <strong>de</strong> 1´s contido no<<strong>br</strong> />
conjunto <strong>de</strong> bits do código (par ou ímpar);
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
<strong>Parida<strong>de</strong></strong> Par e <strong>Parida<strong>de</strong></strong> Ímpar<<strong>br</strong> />
l <strong>Parida<strong>de</strong></strong> Par: o bit anexado serve para<<strong>br</strong> />
tornar o número total <strong>de</strong> 1´s par;<<strong>br</strong> />
Ex. 01001 001001<<strong>br</strong> />
10110 110110<<strong>br</strong> />
l<<strong>br</strong> />
<strong>Parida<strong>de</strong></strong> Ímpar: o bit anexado serve para<<strong>br</strong> />
tornar o número total <strong>de</strong> 1´s ímpar;<<strong>br</strong> />
Ex. 01001 101001<<strong>br</strong> />
10110 010110
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
GERAÇÃO DE PARIDADE PAR<<strong>br</strong> />
- Informação possui número PAR <strong>de</strong> bits 1 bit <strong>de</strong> parida<strong>de</strong> = 0<<strong>br</strong> />
- Informação possui número ÍMPAR <strong>de</strong> bits 1 bit <strong>de</strong> parida<strong>de</strong> = 1<<strong>br</strong> />
Dados<<strong>br</strong> />
P<<strong>br</strong> />
Dados<<strong>br</strong> />
P<<strong>br</strong> />
0000<<strong>br</strong> />
0001<<strong>br</strong> />
0010<<strong>br</strong> />
0011<<strong>br</strong> />
0100<<strong>br</strong> />
0101<<strong>br</strong> />
0110<<strong>br</strong> />
0111<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1000<<strong>br</strong> />
1001<<strong>br</strong> />
1010<<strong>br</strong> />
1011<<strong>br</strong> />
1100<<strong>br</strong> />
1101<<strong>br</strong> />
1110<<strong>br</strong> />
1111<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
GERADOR / VERIFICADOR DE PARIDADE PAR<<strong>br</strong> />
l Porta OU-EXCLUSIVO (X-OR):<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
S<<strong>br</strong> />
A B S<<strong>br</strong> />
0 0 0<<strong>br</strong> />
0 1 1<<strong>br</strong> />
1 0 1<<strong>br</strong> />
1 1 0
GERADOR / VERIFICADOR DE PARIDADE PAR<<strong>br</strong> />
ASSOCIAÇÃO DE PORTAS X-OR<<strong>br</strong> />
l <strong>Parida<strong>de</strong></strong> em palavras com<<strong>br</strong> />
maior número <strong>de</strong> bits;<<strong>br</strong> />
A<<strong>br</strong> />
0<<strong>br</strong> />
B<<strong>br</strong> />
0<<strong>br</strong> />
C<<strong>br</strong> />
0<<strong>br</strong> />
S<<strong>br</strong> />
0<<strong>br</strong> />
l Associam-se n portas X-OR <strong>de</strong><<strong>br</strong> />
duas entradas<<strong>br</strong> />
l Não existem portas X-OR <strong>de</strong><<strong>br</strong> />
mais <strong>de</strong> duas entradas!<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
A<<strong>br</strong> />
S<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
B<<strong>br</strong> />
C<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
S = A ⊕ B ⊕ C
GERADOR / VERIFICADOR DE PARIDADE PAR<<strong>br</strong> />
ASSOCIAÇÃO DE PORTAS X-OR<<strong>br</strong> />
l <strong>Parida<strong>de</strong></strong> em palavra <strong>de</strong> 4 bits;<<strong>br</strong> />
l Associam-se 3 portas X-OR;<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
S<<strong>br</strong> />
C<<strong>br</strong> />
D
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
PORTA XOR DE 4 ENTRADAS<<strong>br</strong> />
l Gerador ou Verificador <strong>de</strong><<strong>br</strong> />
<strong>Parida<strong>de</strong></strong> PAR:<<strong>br</strong> />
Y = A ⊕ B ⊕ C ⊕ D<<strong>br</strong> />
A<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
B<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
C<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
D<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
Y<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
GERAÇÃO / VERIFICAÇÃO DE PARIDADE PAR<<strong>br</strong> />
Dados<<strong>br</strong> />
P<<strong>br</strong> />
Dados<<strong>br</strong> />
P<<strong>br</strong> />
0000<<strong>br</strong> />
0001<<strong>br</strong> />
0010<<strong>br</strong> />
0011<<strong>br</strong> />
0100<<strong>br</strong> />
0101<<strong>br</strong> />
0110<<strong>br</strong> />
0111<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1000<<strong>br</strong> />
1001<<strong>br</strong> />
1010<<strong>br</strong> />
1011<<strong>br</strong> />
1100<<strong>br</strong> />
1101<<strong>br</strong> />
1110<<strong>br</strong> />
1111<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
C<<strong>br</strong> />
D<<strong>br</strong> />
P
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
GERAÇÃO DE PARIDADE ÍMPAR<<strong>br</strong> />
- Informação possui número PAR <strong>de</strong> bits 1 bit <strong>de</strong> parida<strong>de</strong> = 1<<strong>br</strong> />
- Informação possui número ÍMPAR <strong>de</strong> bits 1 bit <strong>de</strong> parida<strong>de</strong> = 0<<strong>br</strong> />
Dados<<strong>br</strong> />
P<<strong>br</strong> />
Dados<<strong>br</strong> />
P<<strong>br</strong> />
0000<<strong>br</strong> />
0001<<strong>br</strong> />
0010<<strong>br</strong> />
0011<<strong>br</strong> />
0100<<strong>br</strong> />
0101<<strong>br</strong> />
0110<<strong>br</strong> />
0111<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1000<<strong>br</strong> />
1001<<strong>br</strong> />
1010<<strong>br</strong> />
1011<<strong>br</strong> />
1100<<strong>br</strong> />
1101<<strong>br</strong> />
1110<<strong>br</strong> />
1111<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
GERADOR / VERIFICADOR DE PARIDADE ÍMPAR<<strong>br</strong> />
l Porta NÃO OU-EXCLUSIVO (X-NOR):<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
S<<strong>br</strong> />
A B S<<strong>br</strong> />
0 0 1<<strong>br</strong> />
0 1 0<<strong>br</strong> />
1 0 0<<strong>br</strong> />
1 1 1
Bit <strong>de</strong> <strong>Parida<strong>de</strong></strong><<strong>br</strong> />
PORTA X-NOR DE 4 ENTRADAS<<strong>br</strong> />
l Detector <strong>de</strong> <strong>Parida<strong>de</strong></strong> ÍMPAR:<<strong>br</strong> />
Y = A • B • C • D<<strong>br</strong> />
A<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
B<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
C<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
D<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
Y<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1
Álge<strong>br</strong>a <strong>de</strong> <strong>Boole</strong>
1. ÁLGEBRA DE BOOLE<<strong>br</strong> />
1.1. POSTULADOS<<strong>br</strong> />
(a) Complemento<<strong>br</strong> />
Ā = complemento <strong>de</strong> A<<strong>br</strong> />
• A = 0 Ā = 1<<strong>br</strong> />
• A = 1 Ā = 0
1. ÁLGEBRA DE BOOLE<<strong>br</strong> />
1.1. POSTULADOS<<strong>br</strong> />
(b) Adição<<strong>br</strong> />
0 + 0 = 0<<strong>br</strong> />
0 + 1 = 1<<strong>br</strong> />
1 + 0 = 1<<strong>br</strong> />
1 + 1 = 1<<strong>br</strong> />
ð<<strong>br</strong> />
ð<<strong>br</strong> />
A + 0 = A<<strong>br</strong> />
A + 1 = 1<<strong>br</strong> />
A + A = A<<strong>br</strong> />
A + Ā = 1
1.1. POSTULADOS<<strong>br</strong> />
(b) Adição
1. ÁLGEBRA DE BOOLE<<strong>br</strong> />
1.1. POSTULADOS<<strong>br</strong> />
(c) Multiplicação<<strong>br</strong> />
0 . 0 = 0<<strong>br</strong> />
0 . 1 = 0<<strong>br</strong> />
1 . 0 = 0<<strong>br</strong> />
1 . 1 = 1<<strong>br</strong> />
ð<<strong>br</strong> />
ð<<strong>br</strong> />
A . 0 = 0<<strong>br</strong> />
A . 1 = A<<strong>br</strong> />
A . A = A<<strong>br</strong> />
A . Ā = 0
1.1. POSTULADOS<<strong>br</strong> />
(c) Multiplicação
1. ÁLGEBRA DE BOOLE<<strong>br</strong> />
1.2. PROPRIEDADES<<strong>br</strong> />
(a) Comutativa<<strong>br</strong> />
ð<<strong>br</strong> />
• A + B = B + A<<strong>br</strong> />
• A · B = B · A<<strong>br</strong> />
(b) Associativa<<strong>br</strong> />
ð<<strong>br</strong> />
• A + (B+C) = (A+B) + C<<strong>br</strong> />
= A + B + C<<strong>br</strong> />
• A · (BC) = (AB) · C = ABC<<strong>br</strong> />
(c) Distributiva<<strong>br</strong> />
ð<<strong>br</strong> />
A · (B+C) = AB + AC
1. ÁLGEBRA DE BOOLE<<strong>br</strong> />
1° TEOREMA DE De Morgan<<strong>br</strong> />
A<<strong>br</strong> />
B AB A+B<<strong>br</strong> />
A · B = A + B<<strong>br</strong> />
ð<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0
1. ÁLGEBRA DE BOOLE<<strong>br</strong> />
2° TEOREMA DE De Morgan<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
A+B A B<<strong>br</strong> />
A + B = A · B<<strong>br</strong> />
ð<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
0<<strong>br</strong> />
0
EQUIVALÊNCIA ENTRE BLOCOS LÓGICOS<<strong>br</strong> />
A S<<strong>br</strong> />
B<<strong>br</strong> />
⇔<<strong>br</strong> />
A S<<strong>br</strong> />
B<<strong>br</strong> />
1º TEOREMA DE DE MORGAN: A·B = A + B<<strong>br</strong> />
Colocando um inversor na saída obtém-se:<<strong>br</strong> />
A S<<strong>br</strong> />
B<<strong>br</strong> />
⇔<<strong>br</strong> />
A S<<strong>br</strong> />
B
EQUIVALÊNCIA ENTRE BLOCOS LÓGICOS<<strong>br</strong> />
A S<<strong>br</strong> />
B<<strong>br</strong> />
⇔<<strong>br</strong> />
A S<<strong>br</strong> />
B<<strong>br</strong> />
1º TEOREMA DE DE MORGAN: A + B = A · B<<strong>br</strong> />
Colocando um inversor na saída obtém-se:<<strong>br</strong> />
A S<<strong>br</strong> />
B<<strong>br</strong> />
⇔<<strong>br</strong> />
A S<<strong>br</strong> />
B
2. ÁLGEBRA DE BOOLE<<strong>br</strong> />
2.4. OUTRAS IDENTIDADES<<strong>br</strong> />
(a) A = A<<strong>br</strong> />
(b) A + A·B = A<<strong>br</strong> />
(c) A + A B = A + B<<strong>br</strong> />
(d) (A + B) (A + C) = A + B·C
Universalida<strong>de</strong> das portas<<strong>br</strong> />
NAND e NOR
UNIVERSALIDADE DAS PORTAS NAND E NOR<<strong>br</strong> />
l Todas as expressões <strong>Boole</strong>anas consistem <strong>de</strong><<strong>br</strong> />
combinações <strong>de</strong> funções OR, AND e NOT;<<strong>br</strong> />
l Portas NAND e NOR são universais, ou seja,<<strong>br</strong> />
po<strong>de</strong>m se “transformar” em qualquer outra<<strong>br</strong> />
porta lógica e po<strong>de</strong>m, portanto, ser usadas<<strong>br</strong> />
para representar qualquer expressão<<strong>br</strong> />
<strong>Boole</strong>ana;
Porta NAND<<strong>br</strong> />
1. INVERSOR a partir <strong>de</strong> uma porta “NAND”<<strong>br</strong> />
TABELA VERDADE<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
S<<strong>br</strong> />
A B S<<strong>br</strong> />
0 0 1<<strong>br</strong> />
0 1 1<<strong>br</strong> />
1 0 1<<strong>br</strong> />
1 1 0
Porta NAND<<strong>br</strong> />
1. INVERSOR a partir <strong>de</strong> uma porta “NAND”<<strong>br</strong> />
A S=A<<strong>br</strong> />
TABELA VERDADE<<strong>br</strong> />
A B S<<strong>br</strong> />
0 0 1<<strong>br</strong> />
0 1 1<<strong>br</strong> />
1 0 1<<strong>br</strong> />
1 1 0
Porta NAND<<strong>br</strong> />
1. INVERSOR a partir <strong>de</strong> uma porta “NAND”<<strong>br</strong> />
A S=A<<strong>br</strong> />
A S=A<<strong>br</strong> />
1<<strong>br</strong> />
TABELA VERDADE<<strong>br</strong> />
A B S<<strong>br</strong> />
0 0 1<<strong>br</strong> />
0 1 1<<strong>br</strong> />
1 0 1<<strong>br</strong> />
1 1 0
Porta NAND<<strong>br</strong> />
1. INVERSOR a partir <strong>de</strong> uma porta “NAND”<<strong>br</strong> />
A S=A<<strong>br</strong> />
A<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
S<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
=<<strong>br</strong> />
A S=A<<strong>br</strong> />
1
Porta NAND<<strong>br</strong> />
2. Porta “AND” a partir <strong>de</strong> duas portas “NAND”<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
S 1 =AB<<strong>br</strong> />
S 2 =AB = AB<<strong>br</strong> />
=
Porta NAND<<strong>br</strong> />
3. Porta “OR” a partir <strong>de</strong> três portas “NAND”<<strong>br</strong> />
Pelo Teorema <strong>de</strong> De Morgan temos:<<strong>br</strong> />
( A · B ) = (A + B) = A + B<<strong>br</strong> />
A S<<strong>br</strong> />
B<<strong>br</strong> />
⇔<<strong>br</strong> />
A S<<strong>br</strong> />
B
Porta NAND<<strong>br</strong> />
3. Porta “OR” a partir <strong>de</strong> três portas “NAND”<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
⇔<<strong>br</strong> />
Inversores<<strong>br</strong> />
A S<<strong>br</strong> />
B
Porta NOR<<strong>br</strong> />
1. INVERSOR a partir <strong>de</strong> uma porta “NOR”<<strong>br</strong> />
TABELA VERDADE<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
S<<strong>br</strong> />
A B S<<strong>br</strong> />
0 0 1<<strong>br</strong> />
0 1 0<<strong>br</strong> />
1 0 0<<strong>br</strong> />
1 1 0
Porta NOR<<strong>br</strong> />
1. INVERSOR a partir <strong>de</strong> uma porta “NOR”<<strong>br</strong> />
A S=A<<strong>br</strong> />
TABELA VERDADE<<strong>br</strong> />
A B S<<strong>br</strong> />
0 0 1<<strong>br</strong> />
0 1 0<<strong>br</strong> />
1 0 0<<strong>br</strong> />
1 1 0
Porta NOR<<strong>br</strong> />
1. INVERSOR a partir <strong>de</strong> uma porta “NOR”<<strong>br</strong> />
A S=A<<strong>br</strong> />
A S=A<<strong>br</strong> />
0<<strong>br</strong> />
TABELA VERDADE<<strong>br</strong> />
A B S<<strong>br</strong> />
0 0 1<<strong>br</strong> />
0 1 0<<strong>br</strong> />
1 0 0<<strong>br</strong> />
1 1 0
Porta NOR<<strong>br</strong> />
1. INVERSOR a partir <strong>de</strong> uma porta “NOR”<<strong>br</strong> />
A S=A<<strong>br</strong> />
=<<strong>br</strong> />
A<<strong>br</strong> />
0<<strong>br</strong> />
1<<strong>br</strong> />
S<<strong>br</strong> />
1<<strong>br</strong> />
0<<strong>br</strong> />
A S=A<<strong>br</strong> />
0
Porta NOR<<strong>br</strong> />
2. Porta “OR” a partir <strong>de</strong> duas portas “NOR”<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
S 1 =A+B<<strong>br</strong> />
S 2 =A+B = A+B<<strong>br</strong> />
=
Porta NOR<<strong>br</strong> />
3. Porta “AND” a partir <strong>de</strong> três portas “NOR”<<strong>br</strong> />
Pelo Teorema <strong>de</strong> De Morgan temos:<<strong>br</strong> />
( A + B ) = (A·B) = A·B<<strong>br</strong> />
A S<<strong>br</strong> />
B<<strong>br</strong> />
⇔<<strong>br</strong> />
A S<<strong>br</strong> />
B
Porta NOR<<strong>br</strong> />
3. Porta “AND” a partir <strong>de</strong> três portas “NOR”<<strong>br</strong> />
A<<strong>br</strong> />
B<<strong>br</strong> />
⇔<<strong>br</strong> />
Inversores<<strong>br</strong> />
A S<<strong>br</strong> />
B
Resumo<<strong>br</strong> />
FIM
FIM