Notes 2 Flashcards
Von Neumann Architecture
CPU <-> Memory
<-> IO Devices
The CPU contains a control unit, an ALU (arithmetic and logic unit), and a register file
Digital
has discrete values separated by gaps
ex. digital clocl
Analog
continuous
no gaps
High is also known as
power
5V
Vhigh
ON
True
Vcc
1
Low is known as
GND
ground
0V
OFF
False
0
_’s and _’s are literally the presence or absence of voltage on a wire (the digital part of a digital system)
1’s and 0’s
AND truth table
A B | AB
0 0 0
0 1 0
1 0 0
1 1 1
OR truth table
A B | A+B
0 0 0
0 1 1
1 0 1
1 1 1
NOT truth table
A | A’
0 1
1 0
XOR Truth Table
A B | A⊕B
0 0 0
0 1 1
1 0 1
1 1 0
A’B+B’A
exclusive or
NAND truth table
A B | AB
0 0 1
0 1 1
1 0 1
1 1 0
Not A and B
NOR truth table
A B | A+B
0 0 1
0 1 0
1 0 0
1 1 0
negating results of or
And Gate
Draw it
Or gate
Draw it
Not gate
draw it
XOR gate
draw it
NAND gate
draw it
NOR gate
draw it
practice analyzing circuit diagrams
draw a diagram from the equation : A + AB
draw a diagram from the equation : (A+B)(B+C)
A’B’ + AB
Boolean Identities Part 1:
X+0 =
X+1 =
X1 =
X+X =
XX =
X*0=
X+0 = X
X+1 =1
X1 = X
X+X = X
XX = X
X*0=0
Boolean Identities part 2:
X +X’ =
X * X’ =
(X’)’ =
X+Y =
X*Y =
X +(Y+Z) =
X +X’ = 1
X * X’ = 0
(X’)’ =X
X+Y = Y+X
XY = YX
X +(Y+Z) =(X+Y)+Z
Boolean identities part 3:
X(YZ) =
X(Y+Z) =
(X+Y)(X+Z)=
(X+Y)’=
(XY)’=
X(YZ) = (XY)Z
X(Y+Z) = XY +XZ
(X+Y)(X+Z)=X+YZ
(X+Y)’=X’ n Y’
(XY)’= X’ + Y ‘
