4.6 Logic Gates Flashcards
What are the six main Boolean Operations
1) AND
2) OR
3) NOT
4) NAND
5) NOR
6) XOR
What is the AND operation?
All inputs must be true to generate a True Output
A.B
What is the OR operation?
Returns a TRUE result when any of the inputs are true
A = 1 B = 1 Output = 1
What is the NOT operation?
The NOT statement inverts the input so that TRUE becomes FALSE and FALSE become TRUE
What is the NAND operation?
The NAND produces a TRUE result in any of the inputs are FALSE
What is the NOR operation?
The NOR statement produces a TRUE value if all of the input values are false
What is an XOR operation?
The XOR operation produces a TRUE result only when one of the inputs is true and the other one is false
A (+) B
What is an edge-triggered D-type flip flop?
1) An edge-triggered D-type flip flop is a memory unit that changes state with each pulse of the clock
2) For each pulse of the clock data coming from the input will be stored in the flip flop and will continue to be output until the next trigger pulse is received
What is an adder and what types are there?
1) An Adder is found in the Arithmetic Logic Unit (ALU) of the CPU and are used to add binary values together
2) There are two main types:
- Full Adder: Circuit that does addition using A and B inputs and a carry bit ( 3 inputs A B inputs 1 more input is carried, 2 outputs Sum + Carry bit)
- Half Adder: Circuit that performs addition using just A and B inputs only (2 inputs carry bit is stored with result S + C together)
What is a clock?
A device that creates a signal that is used to synchronise the components of a computer
What is a flip flop?
A memory unit that can store one bit
What is De Morgans Law?
De Morgans law is a method that can be used to simplify Boolean Algebra expressions by inverting all the variables
What are the principles of De Morgans Law?
NOT (A AND B) = (NOT A) or (NOT B)
NOT (A OR B) = (NOT A) AND (NOT B)
