C D E F
G H I J K L
M N O P
Q R S T U
V W X Y Z
- active high signal
- a signal that is considered asserted when
it is HIGH or 1.
- active low signal
- a signal that is considered asserted when
it is LOW or 0.
- address bus
a set of signal lines between the processor
and memory or I/O that carry the address (location)
of a memory or I/O access. The address space
of the processor (the maximum number of memory locations that can potentially
be accessed) is determined by the number of these signal lines.
- address strobe
a signal output from the processor that indicates
when a valid address is present on the address
a sequence of steps used to solve a particular
- AC (alternating current)
an electric current that alternates its direction
of flow. The frequency of alternating current is measured in hertz,
or cycles per second.
a unit used to measure current. One ampere
corresponds to the amount of current flowing
through a resistance of one ohm at one volt potential difference.
- ampere hours
a measurement of battery cell
capacity that equals the number of hours a cell
can supply a certain amount of current before its voltage drops below
a predetermined threshold value.
the magnitude of the signals in a waveform,
usually expressed in voltage.
characterized by a continuously variable range
of signal levels, as opposed to digital,
where signal magnitude can only take on discrete values.
- analog multiplexer
a component that selects an analog
output signal from a number of analog inputs.
An address value
sent to the multiplexer determines which of the inputs is selected.
See multiplexer and analog
- AND gate
a type of logic gate that outputs
a 1 (true) only when all inputs are 1. AND gates have two or more inputs.
See also NAND gate.
a positive electrode.
a value or expression that is passed to a
a sequential list of data values of the same
pronounced `askee,' an
acronym for American Standard Code for Information Interchange, a coding
scheme that assigns numeric values to letters, numbers, punctuation
marks, and other characters. For example,
the letter A is represented by the number 65 in ASCII.
- assembly language
a type of low-level programming language in
which each statement corresponds directly to a single processor-specific
instruction. Assembly language programs can be written either by hand
or generated by a compiler.
A program known as an assembler translates the assembly language into
the shaft on which a wheel or gear is mounted.
- back electromagnetic
a potential difference caused by the turning
of a motor. When a motor is turned, it essentially becomes a generator,
and produces a voltage difference at its terminals. Resistance to changes
in this voltage difference produces resistance to the turning of the
a device that uses a chemical reaction to
produce electrical energy.
- bend sensor
a resistive sensor whose resistance is proportional
to how much the sensor is bent. The higher the bend, the higher the
a voltage applied to a transistor
or other electronic device in order to establish a reference level for
binary refers to the base-2 number system,
in which values are expressed as sequences of binary digits (bits).
Thus, the only allowable numerals in a binary number are 0 and 1.
- binary program
another name for the object code translation
of an assembly program.
short for binary
digit; the smallest unit of information handled by a computer. Each
bit represents either a 0 or 1.
- bitwise operators
Operators that perform functions on specific
bits in a byte
(testing, setting, or shifting) rather than the byte as a whole.
a section of code
in which local variables can be declared.
- board, or printed
a broad term referring to a flat circuit board
used to hold chips and other electronic components as well as to provide
connections between the components. The largest board used
- in ELEC 201 is called the RoboBoard.
- Boolean logic
a type of algebraic logic where every answer
is either true or false; digital processors use Boolean logic extensively,
since each answer can be represented by a bit,
which is either 1 or 0, true or false. Some programming languages support
a Boolean data type with predetermined values for true and false; others
use integer data types to implement Boolean values, where zero equals
false and non-zero values equal true.
the upper or lower limit in a permitted range
a special signal used to interrupt a program
- bridge rectifier
a circuit that assists in converting alternating
current to direct current.
section of memory set aside for temporary
any problem in a piece of hardware
or software that keeps it from running properly.
a set of signal lines (wires) used to transfer
information between several components in parallel.
- bus contention
a situation that occurs when two or more components
try to simultaneously access the same bus.
a unit of information consisting of 8 bits.
to compare an instrument or device against a standard to
determine its accuracy, or to provide a reference level.
a statement that causes the code in a
function or subroutine to be executed.
one method of passing variables to a function in which the address of the desired variable is passed
as an argument to the function rather than a copy of its value.
Code within the function can read and modify the original variable using this address.
another method of passing a variable to a function. A copy of
the variable is passed as an argument to the function. Since
this is only a copy, the function cannot modify the value of the original variable.
a component that can store electrical energy. It is made up of
two conductive surfaces separated by an insulating material known as a dielectric.
- case sensitive
distinguishes between upper and lower case. The IC Programming
Language, for example, is case sensitive.
a negative electrode.
a (see battery).
- cell capacity
the amount of current
that a cell can supply for a period of time, usually measured in ampere-hours.
any single text symbol such as a letter, number, or punctuation
- character string
a sequence of consecutive characters.
- clicking on
in terms of a computer, refers to moving the cursor over an
object to be selected (such as a button), and pushing the mouse button to activate the
refers to the clock on the RoboBoard, based around a
crystal-controlled oscillator circuit. The crystal is set to
resonate at a specific frequency and produces an analog sine
wave. The frequency generated by the clock is the master frequency of the board.
- closed-loop control
method of controlling the robot where the action being performed
sends information back to the microprocessor about the action's effect on the robot's
the a computer program, or section of a program.
to change a value from one data type to another so that it can
be used in a particular function.
- cold solder joint
an improperly soldered connection caused by failure to
adequately heat the joint during soldering. Cold solder joints appear dull and do not
conduct electricity well.
- color code
a system of colors used to indicate the electrical value of a
component. Resistors have bands of color on them to indicate their resistance.
Also, see Resistor Color Code Table.
- command line
the line on a computer screen on which commands are entered.
see resistor pack.
- compile-time error
an error in the source code of a
program that is detected while it is being compiled.
a program that translates high-level programming languages into
instructions called machine or object code that a machine can understand.
- component side
the side of a board on which components are placed.
- CPU(Central Processing Unit)
the chip inside a computer responsible for essential control and
computational functions. Also called a ``processor'', the RoboBoard's is a M68HC11, or
simply the 'HC11.
the result of a run-time error. This usually causes the system
to hang or lock-up.
- data bus
a set of signal lines connecting a processor, its memory, and
peripherals that carry the data associated with a memory access. The address of the access is provided by the address bus.
- DC motor
a motor designed for direct current operation; easy to reverse
and control speed.
The process of accessing a variable through a pointer.
the process of diagnosing and correcting problems.
a multiple-input, multiple-output logic device that converts
coded inputs into coded outputs, where the input and output codes are different. A 3-to-8
decoder, for example, uses a three bit binary
input to select one of eight output lines. Also called a ``demultiplexer''.
- default value
a value automatically determined for something, such as a
variable, if no other user-specified value is assigned to it.
- desoldering pump
a tool used to remove solder from a joint.
- desoldering wick
resin-coated copper braid used to remove solder.
the insulating material between plates of a capacitor or between any two parts in an electric circuit.
characterized by representation as discrete
values, as opposed to analog .
- digital input/output
digital signal lines used to transfer
discrete information between the processor and devices such as sensors, motors, and lamps.
a device that passes current only in one direction, sometimes
called a rectifier.
- DIP(dual-inline package)
the standard bug-like package characteristic of most low density
computer chips. Its pins are arranged in two parallel rows.
- DIP socket
a socket that holds chips, so that
chips themselves are not actually soldered to the board. As with chips, the sockets
require attention to proper orientation when mounting.
- DIP switch
small toggle switches on a board that are set to control various
aspects of the board's operation.
- discharge curve
a curve showing the voltage as a battery
discharges. Different types of battery have characteristically different discharge curves.
to receive information (usually a file) from another computer.
a piece of software that tells the computer how to communicate
or operate with a certain piece of hardware or software.
- dynamic RAM
random access memory whose stored data must be refreshed
periodically by reading the data and writing it back to the same location. If this is not
done, the data will be lost.
a see multiplexer
/ee-prom/Erasable Programmable Read-Only Memory; A type of
non-volatile memory chip that can be programmed electrically and erased by exposing the
chip to ultraviolet light.
/ee-ee-prom/ ``Electrically Erasable Programmable Read- Only Memory'' - A type
of non-volatile memory chip that can be both programmed and erased electrically.
one of the plates of a battery or electrolytic capacitor.
- electrolytic capacitor
a fixed value capacitor in which the dielectric is a thin film formed on the surface of an aluminum electrode by a liquid or paste electrolyte (a substance that
- electromotive force
a voltage or potential.
the performance of one or more instructions, usually involving the loading of machine code into memory and the carrying out of the specified
a unit of capacitance.
output from a system that is returned to the same system for the
purposes of making control decisions.
- feed forward control
a type of open loop control where the control signal is a
function of some parameters measured in advance.
- female connector
a type of connector with one or more
receptacles for the insertion of pins.
- female socket header
a type of female
connector whose receptacles are arranged in two adjacent rows, usually used for cables.
a type of variable in floating-point (exponential) form.
the pattern on a printed circuit board to which the component
leads are mated. See also pad.
- for loop
a programming command that executes a section of code
a specified number of times.
how often something happens, measured in hertz, which
is one cycle or vibration per second.
- function call
a reference to a function in a section of code 68HC11
that executes the function.
- function declaration
the ``title'' of a function that lists its type (void, int,
float, etc.) as well as any variables that may be passed to that function.
an electronic switch that follows a rule of Boolean
logic, such as AND, OR, or NOT.
a measurement of magnetic flux density.
a toothed wheel used to transfer mechanical energy.
- gear reduction
The technique of attaching a small gear to a larger gear to
increase torque at the expense of rotation speed.
- global variable
a variable whose value can be accessed and modified by any
statement in a program. In other words, it is visible to the entire program (see local
a connection between an electric circuit and the earth, the
common point (e.g. 0V) to which all signals in a circuit are referenced.
a circuit commonly used to drive motors.
- Hall effect sensor
an electromagnetic sensor that detects changes in
- heat shrink tubing
rubber tubing that is used to protect soldered joints. It is
initially large and flexible, but shrinks and becomes stiff when heated.
a device that absorbs and dissipates heat produced by an
electrical component; used to prevent overheating.
the base-16 number system. In order to count to 32 in hex, the
following would be the sequence of numbers: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E,
F, 10, etc.
a type of information structure that is non-sequential and
associative, linked in such a way so that when more information is sought about a word,
simply clicking on that word in the document brings it up.
a form of programming statement. When the if expression
is true, then the statement following the if expression is executed; when that
expression is false, the else statement is executed.
- incandescent lamp
a lamp with a filament that heats and emits white light when
current runs through it.
the process by which an object is electrified, magnetized, or
given an induced voltage by exposing it to a magnetic field.
a device possessing the ability to
store energy in the form of a magnetic field; an inductor passes direct current, but
blocks alternating current to a degree, depending on its frequency.
range of invisible light radiation frequencies lying between
visible red and radio waves on the spectrum.
to prepare something for use. A computer initializes itself each
time it is started up.
a non-conductive material, used to separate elements of
circuits; rubber, glass, ceramic, and plastic are all good insulators.
- integrated circuit
also called an IC, an integrated circuit consists of a single
chip (usually silicon) with many components such as transistors and resistors fabricated on it. Integrated circuits
contain anywhere from a few tens to many millions of components. Most of the ICs on the
RoboBoard are MSI (medium scale integration), chips that contain anywhere from 20 to 200
- Interactive C
a version of the C programming language used in ELEC 201; interactive
suggests that the user has added control over what is going on.
- internal resistance
the natural resistance of a battery,
generator, or circuit component, which determines the
- maximum rate at which power can be
a piece of software that directly executes source code without first compiling and storing the code in an
a special processor function that halts normal
execution in response to some event such as a timer expiration or successful transmission
of a character to an I/O device. When
the interrupt is encountered, the processor executes a special interrupt handler routine
to process the event.
a programming method in which code is only executed in response
to events that cause interrupts.
a logical function that returns the opposite of the input.
Equivalent to a NOT gate. Also a device that changes direct current into
- isolated element resistor pack
see resistor pack.
circuit or circuit element used to maintain a particular state,
such as logical true or false, on or off.
a connecting wire, such as a test lead, battery
- lead-acid cell
common type of rechargeable battery cell in which sulfuric acid reacts with
lead to produce electricity.
- LED(light-emitting diode)
a semi-conductor device that converts electrical energy into
- LCD(liquid crystal display)
a display comprised of a polymer, a thin grid of electrodes, and two polarizing filters with their polarizing planes
at right angles to each other. Light is either passed through the filters or blocked by
aligning the molecules by means of the electric field from the electrodes. Blocking the
light produces black regions on the display to create an image.
- Lenz's Law
a principle which states that induced current flows in the
opposite direction as the motion that generated it.
a file containing standard functions that may be used by a
program. Library functions usually perform very specific tasks, and using them can
simplify work when a particular function needs to be carried out repeatedly in a program.
- local binding
a term meaning a variable is defined only within the context of
a particular function, not the whole program.
- local variable
a variable declared inside a function. These variables can only
be referenced by statements inside the block where they are declared.
a set of commands that repeat until a certain condition is
- machine code
(See object code).
- magnetic shaft encoder
a device that uses a magnetic sensor to detect rotation.
- male connector
a type of connector with one or more
pins, as opposed to receptacles.
- male socket header
a type of male
connector whose pins are arranged in one or more rows, usually used for cables.
an SPI participant that controls data flow to other SPI systems.
- megahertz (MHz)
a frequency measure corresponding to a signal that oscillates at
one million cycles per second. Megahertz is often used when referring to the clock speed
of a computer.
- memory effect
a phenomenon observed in rechargeable nickel cadmium cells where
cells only partially discharged before
recharging tend to ``remember'' the level of discharge. These cells eventually become
usable only to that level of discharge.
- memory enable control line
the signal directly asserted by the processor when a memory
module is to be accessed. This signal enables or ``turns on'' the memory chip and allows
data to be read from or written to the memory module.
- master in slave out
abbreviated MISO, this data line supplies the output data from a
slave to the master. No more than one slave can transmit data at any given time.
- modulated infrared light
infrared light made to vary in intensity, in accordance with
variations in another signal.
to vary the amplitude,
frequency, or phase of a carrier wave, usually to transmit information.
- master out slave in
abbreviated MOSI, this data line supplies the output data from
the master that is shifted into the input(s) of the slave(s).
test instrument with a number of different ranges for measuring current, voltage, and resistance.
a circuit that allows only one of several digital inputs to be slected (and output) at a
a mode of operation where more than one sequence of computation
is active at the same time.
- NAND gate
a type of logic gate that outputs a 0 only when all inputs are
- native language (also: host language)
language supported by a particular computer system (the host) in
the absence of software to create the support. Strictly speaking, native language refers
to the central processing unit's
(CPU's) machine language, but the term is sometimes applied to a high-level language
specifically supported by the operating system.
- negative feedback loop
a type of control where the feedback helps to correct an error,
making the degree of error smaller.
- negative logic
logic that uses active
low signals. See also active low.
- nickel cadmium cell
type of rechargeable cell with moderate power density and low internal resistance.
- nominal cell voltage
the voltage produced by the chemical reactions in an electrochemical cell.
- non-volatile memory
storage system that does not lose information when its power is
- NOR gate
a type of logic gate that returns a 1 only when all inputs are
- NOT gate
a type of logic gate that returns the opposite of its input.
having no meaning, in the sense that it does not cause any action and holds no meaningful
value. Null can be used for many purposes, such as receiving test output in a program, to
separate blocks of information, or to terminate strings.
a four bit hexadecimal digit equal to half of a byte. Also spelled nibble.
- object code
code that is generated by a compiler
or assembler from the source code of a program (in ELEC 201, the IC code is the source
code). Object code generally refers to the instructions that can be directly executed by
the central processing unit (CPU).
- Ohm's law
a fundamental electrical law expressing the relationship between
voltage, current, and resistance in a DC circuit: voltage (V) = current
(I)×resistance (R) .
The unit of electrical resistance. One ohm corresponds to the
resistance at which one volt can maintain one ampere of current.
instrument for measuring resistance.
- open-loop control
method of controlling the robot where the action being performed
sends no feedback to the microprocessor on the action's effect on the robot's state;
open-loop control works best when a robot functions under very reliable conditions.
- OR gate
a type of logic gate that returns a 0 only when all inputs are
a device that displays on a screen (cathode ray tube) how a
voltage or current signal varies over time.
a conductive patch on the surface of a printed circuit board to
which leads are connected.
- p-code (pseudo code)
machine language for a hypothetical
processor. P-code requires a software interpreter for execution.
- parallel (circuit) connection
way of connecting two or more components such that the two ends
of each component are connected together. Thus, the voltage is the same across all of the
components, but the current is divided between them (See also series circuit).
Figure E.1: Parallel Connection of
Components A,B, and C
- parallel port
a port that allows data to flow in more than one bit
at a time, typically with one separate wire for each bit.
printed circuit board; an epoxy glass and metal composite on
which circuits are etched and to which active, passive and hardware
components are attached.
in computer terms, any piece of the computer apart from the CPU and memory.
- persistent global variable
type of global variable that keeps its value even when the robot
is turned off or reset. Downloading will usually destroy the values of persistent globals.
relative measurement describing the temporal relationship
between two waves with the same frequency. Phase is measured in degrees, and one full
oscillation cycle has 360 degrees. One way to think of phase: If two pendulums are
swinging at the same frequency and are in the same position at the same instant, then they
are in phase with each other.
- phase-locked loop
a device that keeps the phases of two signals constant, relative
to each other.
a light-sensitive cell
whose resistance changes when exposed to light.
a semiconductor controlled by light rather than an electric
- picofarad (pF)
- Piezo beeper
a component containing a crystal that makes noise when an
electric current is applied.
slender prongs, usually referring to the contacts sticking out
of a male connector or the ``legs'' on
- PLCC (plastic leadless chip carrier)
a variation of an LCC, which is a method of mounting chips on
boards using contacts instead of leg-like pins. The chip simply rests in a socket
that has contacts on its base for completing the connection.
a variable that contains a memory address. Usually this address is the location of another variable
in memory. Pointer variables much be declared as such, and the variable type must match
the type of the variable being ``pointed'' to.
the sign of the potential (voltage) between two points in a
circuit. When a potential difference exists between two points, one end has a positive
polarity and the other one, negative polarity. Electrons flow from negative to positive,
but by convention, current is considered to flow from positive to negative.
- polarized component
a circuit component that must be installed with its leads in a
particular orientation with respect to the direction of current flow (or polarity) of the
circuit. Examples of such components: diodes,
rectifiers, and some capacitors.
- polarizing filter
transparent piece of glass that only lets light waves vibrating
in a certain direction pass through.
- positive logic
logic in which active
high signals are used. See also active high.
the difference produced by an imbalance in the charge
distribution that causes the movement of charge carriers in a conductor.
Also called voltage.
(commonly called a pot) a circuit element that can be adjusted
to provide varying amounts of resistance.
- power density
the capacity per unit weight of a battery
- precedence of operators
the default order in which mathematical operations are
- process identification number
(pid) the number assigned to a process when it is called using
the IC function call start
process(). This number can be used to later kill the process.
- process table
a table used by the processor to keep track of all running
- program counter
a register that contains the address of the next instruction to be executed.
- program stack
memory used by a process to pass arguments
for function calls, to store local variables, and to store
return addresses from function calls. The size of the stack is defined at the time the
process is created.
- pull-up resistor
a resistor connected to the supply voltage to provide drive current to a gate.
- pulse width modulation
method of encoding information by varying the shape of a series
of pulses. The unmodulated signal consists of a continuous pulse train of constant
frequency, duration, and amplitude;
during modulation, pulse durations (or widths of pulses) are changed to reflect the
information being encoded.
- RAM (random-access memory)
memory that can be read and written by the microprocessor and
other hardware devices. Storage locations can be accessed in any order (hence ``random
access'' RAM is usually volatile, meaning its contents are lost when power is removed.
- rated output
power, voltage, or current a device
will provide when operating under normal circumstances.
- ROM (read-only memory)
memory containing instructions or data that can be read but not
modified. As a general term, ROM can refer to PROM or EPROM.
- read-write control line
line that controls whether a device is to perform a read
function or write function.
- rectifier (a.k.a. diode)
a circuit component that passes current
in one direction and blocks current flow in the other direction. A rectifier is used to
convert alternating current into direct current.
the act of a function calling itself.
the quality that impedes the flow of electric current.
All materials have some degree of inherent resistance. Substances with low resistance
(such as metals) conduct electricity well and are called conductors.
Substances with very high resistance are called insulators or
circuit component designed to provide a specific amount of
resistance to current flow.
- resistor package
Resistor packs are flat, rectangular packages with anywhere from
six to ten leads. Two basic types of resistor packs are isolated element containing discrete resistors, and common terminal that contain
resistors with one pin tied together and the other pin free.
- return value
the value that a function returns when it has finished
An international standard for serial communication
- run-time errors
errors that occur in a program while it is executing (as opposed
a diagram that shows the electrical connections of an electronic
component by means of symbols used to represent the parts and lines to represent wires
connecting the parts.
material with generally high resistive properties, but which
conducts under special conditions. The semiconductors used to make ICs are generally
fabricated from the element silicon.
- serial communication
transmission of information between computers and peripheral
devices one bit at a time over a single line. Serial
communication requires that both sender and receiver use the same communication
- serial port
a port that sends bits one at a time, in a single stream,
typically consisting of a line for sending data, one for receiving, and one or more other
lines for regulating the transmissions over the send and receive lines. A common type is
an RS-232 port.
- serial clock
abbreviated SCK, a control line driven by a master SPI system
that regulates the flow of data bits. The master may transmit
data at different baud rates. The SCK
line cycles once for each bit that is transmitted.
- series (circuit) connection
a circuit in which components are connected together end to end.
Although current passes through each of the components, voltage is divided among them.
(See also parallel connection).
Figure E.2: Series Connection of
Components A,B, and C
- servo motor
motor whose output shaft does not rotate freely, as in a DC motor, but moves to a certain angular
a bar supporting, or transmitting motion to, a mechanical part.
- short circuit
low-resistance connection across a voltage source, or between
the sides of a circuit or line. Also called simply a ``short'', these typically result in
excessive (and potentially damaging) current flow.
- signal demodulation
the process of extracting the frequency component from a
- SIP(single in-line package)
a package type in which pins are arrange in a single line. Some
of the resistor packs (RSIPs) on the RoboBoard are of this package type.
an SPI participant that responds passively to data transfer
actions initiated by the SPI system master.
- slave select
abbreviated SS, a control line that allows slave SPI systems to
be turned on and off with hardware control.
- slotted optical switch
a component containing a light source and a sensor aimed at each
other. The sensor detects when the light source is not blocked, say by a slotted wheel
turning between the two.
mounting device for plug-in coils, plug-in capacitors, plug-in resistors and crystals having holes with spring
clips arranged to fit and grip the terminal prongs of the component being plugged in.
an alloy of tin and lead that melts at a fairly low temperature
and is used for making permanent electrical connections between parts and wires.
- soldering iron
a device for applying heat to a joint, melting the solder so
that it creates a permanent joint.
serial peripheral interface.
region of memory in which programs store status data, such as
function call return addresses, passed parameters, and sometimes local variables. The
program, microprocessor and operating system can all maintain one or more separate stacks.
- stack pointer
a register that keeps track of the current location in the
an individual C command. For example, var1 += var2;.
- static RAM
a kind of RAM that can hold a logic high or logic low state as
long as there is electricity applied. The logic states are lost in static RAM only if
erased by the programmer or if the electricity is turned off. Static RAM does not have to
be refreshed as long as the power is on.
- stalled state
the state when a motor is producing the maximum amount of
torque, but is not rotating.
- stepper motor
a motor whose rotation is in discrete
steps rather than continuous movement.
- SMD(surface-mounted device)
a type of package for an integrated circuit that, as its name
implies, is mounted on the surface of the printed circuit board (as opposed to its pins
being inserted through the PCB).
an one dimensional array of characters.
- tantalum capacitor
a type of polarized capacitor.
- task manager
tracks the progress of and provides necessary resources for
separate tasks running on one processor.
in electronics, a point that can be physically connected to
something else, usually by a wire, to form an electrical connection
a point at which an effect can be seen. For example, the
threshold voltage of a transistor is
the minimum voltage that must be applied to the base before any current will flow through
the transistor; a test value.
units of time.
a loop exit condition for which a loop is exited after a
predetermined amount of time if the condition is not met.
covering the soldering iron tip or the tip of a wire with
as a noun, a device with two states or a program option that can
be turned on or off using the same action (like a mouse click); as a verb, to toggle is to
switch back and forth between two states.
- tolerance band
colored band on a component indicating the permissible variation
from the rated or assigned value.
the rotary force produced on a motor's output shaft
component that can both transmit and receive signals.
a device that converts energy from one form to another,
retaining the amplitude variations of
the energy being converted. Examples include a microphone, which converts acoustical
energy into electrical energy; a loudspeaker, that does the reverse; a photocell that
converts light energy to electrical energy.
a circuit component (usually with three leads) that can serve
several functions- amplifier, switch, or oscillator, among others. The three leads of a
transistor are the emitter, base, and collector, and in the most common mode of operation,
a large current flow between the collector and emitter terminals is controlled by a small
current applied to the third terminal, the base. The current can be turned on and off,
causing the transistor to behave as a switch.
used to describe a change that is made, or an operation that is
performed, that has no effect with respect to the user.
- unloaded speed
the speed at which a motor runs when there
is nothing connected to the shaft.
- value types
the various formats for data to be used in
a program; the value type must be specified when a variable is declared.
Value types in IC include integer
(int), floating-point (float) , and character
- variable resistor
a resistor with a sliding contact that permits
changing the resistance value.
- value mantissa
the decimal part of a floating-point number.
- volatile memory
a storage system that loses its data when
removed from a power supply.
- voltage divider
two resistors in series connected across a
voltage source. The voltage at the common centerpoint is a fraction
of the total applied voltage, determined by the resistor values.
- voltage drop
voltage developed between terminals of a component
by current flow through the resistance of that component.
another type of loop in C, whose form is while(condition
== true) statement; A statement can range from a
single instruction to a block of instructions that repeat. The condition
may be any expression, and true is any non-zero value. The
loop iterates while the condition is true. When the condition becomes
false, program execution continues with the line following
the loop code.