ASCII Code Table 7 bit

1
ASCII Code Table (7 bit)
UNICODE (16 bit) - UTF-8 provides a 16 bit
superset of ASCII
2
2s Complement Sign Extention

• Positive numbers
• Negative numbers

3
2s Complement Arithmetic

• Addition
• Subtraction
• Multiplication, Division ?

4
Round off Errors

• Errors due to inherent imprecision of computers /
  computation

5
Overflow

• Adding two numbers which results In a sum that is
  too large to store
• A B
• A - B

6
Underflow

• A calculation in floating point that results in
  an intermediate result that is essentially zero.

7
Floating Point Numbers

• Example -56.67534 x 10-5
• Sign
• Fraction
• Exponent

8
Single Precision Floating Point NumbersIEEE
Standard

• Single Precision Floating Point Numbers are 32
  bits long
• S EEEEEEEE FFFFFFFFFFFFFFFFFFFFFFF
• Sign 1 bit
• Exponent 8 bits
• Fraction 23 bits
  
• The value V
• If E255 and F is nonzero, then V NaN ("Not a
  number")
• If E255 and F is zero and S is 1, then V -
  Infinity
• If E255 and F is zero and S is 0, then V
  Infinity
• If 0ltElt255 then V (-1)S 2 (E-127)
  (1.F)
• If E0 and F is nonzero, then V (-1)S 2
  (-126) (0.F) ("unnormalized" values)
• If E0 and F is zero and S is 1, then V - 0
• If E0 and F is zero and S is 0, then V 0

9
Double Precision Floating Point NumbersIEEE
Standard

• Double Precision Floating Point Numbers are 64
  bits long
• S EEEEEEEEEEE FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
  FFFFFFFFFFFFFFFFFF
• Sign 1 bit
• Exponent 11 bits
• Fraction 52 bits
  
• The value V
• If E2047 and F is nonzero, then V NaN ("Not
  a number")
• If E2047 and F is zero and S is 1, then V -
  Infinity
• If E2047 and F is zero and S is 0, then V
  Infinity
• If 0ltElt2047 then V (-1)S 2 (E-1023)
  (1.F)
• If E0 and F is nonzero, then V (-1)S 2
  (-1022) (0.F) ("unnormalized" values)
• If E0 and F is zero and S is 1, then V - 0
• If E0 and F is zero and S is 0, then V 0

10
Chapter 3 Digital Logic Structures

• The Transistor
• CMOS Devices
• Implementing Logic with CMOS Devices
• Combinational Logic Circuits
• Decoders
• Muxs
• Full Adder
• PLAs

11
Introduction to MOS

N-type MOS
12
N-Type MOS Devices
13
P-Type MOS Devices
14
CMOS Device - Inverter
3-5 volts
p channel device
CMOS Inverter
n channel device
15
CMOS NOR Gate

NOR Gate
16
CMOS OR Gate

OR Gate
17
CMOS AND Gate

AND Gate
18
2 BIT Decoder