Learning Guide Unit 2/3 Flashcards
More computer stuff.
What is N-Type Silicon ‘doped’ with?
Arsenic, Phosphorus, Antimony
What is P-Type Silicon ‘doped’ with?
BGA
Boron, Gallium, Aluminum
2’s Complement is also known as?
Radix complement
What is -8 in 2’s Complement?
1000
What is the 2’s complement of 0001?
1111 = -1
A special-purpose chip designed to add 1 to a given number.
Incrementer
This chip was designed to add three bits.
Full-Adder
A “ “ consists of logic gates whose outputs, at any time, are determined by combining the values of the inputs.
Combinational Circuit
Source: Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
For n input variables, there are “ “ possible binary input combinations.
2n
Source: Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
How many possible outputs are there for each binary combination of the input variables?
One.
Source: Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
A combinational Circuit can be described by? Hint: 2 answers
- A truth table that lists the output values for each combination of the input variables, or
- m Boolean functions, one for each output variable
Source: Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
Combinational circuits are “ “. Thus, the output value depends ONLY on the current input values.
Memory-less.
Source: Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
What two things do sequential circuits consist of?
Hint: how do they remember?
Combinational logic as well as memory elements (used to store certain circuit states). Outputs depend on BOTH current input values and previous input values (kept in the storage elements).
Source: Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
What type of decoder is this? For each possible input combination, there are seven outputs that are equal to 0 and only one that is equal to 1.
3-to-8 Line Decoder.
Source: Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
The decoder is also used in conjunction with other code converters such as a “ “ decoder.
BCD-to-seven_segment decoder.
Source:
Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
A decoder with an enable input is referred to as a?
Decoder/Demultiplexer
Source: Taipala, D. (2013, June 6). CS1104 computer systems unit 3 lecture 1
This device uses a set of control inputs to select which of several data inputs is to be connected to a single data output.
A multiplexer
The simplest output from a digital circuit is an?
LED (Light-Emitting Diode)
What circumstances would cause an LED to not light up? Hint: 3 potential answers.
- If there is no current
- If the current tries to flow in the opposite direction
2a. You may also have the LED turned around.
How do you reduce the current to an LED?
With a resistor.
Selects or enables a specific device or it routes data to the appropriate subsystem.
Scheme
What is an Active-Low Operation?
Using Logic 0 to enable devices and a logic 1 to disable them.
What is the special notation that is used to indicate an active-low signal?
The signal input has a bar over it or sometimes the line that is drawn into or out of the system diagram will also pass through an inverter circle to identify the signal as active-low.
The simplest input to a digital circuit is a?
switch
What is a pull-up resistor?
A pull-up resistor protects the integrated circuit by limiting the current flow while still providing a positive voltage that can be read as a logic one.
