Cypress PSoC CY8CTMG20 Series, Техническое справочное руководство

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296 PSoC CY8CTMG20x and CY8CTST200 TRM, Document No. 001-53603 Rev. *C
Glossary
multiplexer (mux) 1. A logic function that uses a binary value, or address, to select between a number of inputs
and conveys the data from the selected input to the output.
2. A technique which allows different input (or output) signals to use the same lines at different
times, controlled by an external signal. Multiplexing is used to save on wiring and I/O ports.
N
NAND See Boolean Algebra .
negative edge A transition from a logic 1 to a logic 0. Also known as a falling edge.
net The routing between devices.
nibble A group of four bits, which is one-half of a byte.
noise 1. A disturbance that affects a signal and that may distort the information carried by the signal.
2. The random variations of one or more characteristics of any entity such as voltage, current,
or data.
NOR See Boolean Algebra .
NOT See Boolean Algebra .
O
OR See Boolean Algebra .
oscillator A circuit that may be crystal controlled and is used to generate a clock frequency.
output The electrical signal or signals which are produced by an analog or digital block.
P
parallel The means of communication in which digital data is sent multiple bits at a time, with each simul-
taneous bit being sent over a separate line.
parameter Characteristics for a given block that have either been characterized or may be defined by the
designer.
parameter block A location in memory where parameters for the SSC instruction are placed prior to execution.
parity A technique for testing transmitting data. Typically, a binary digit is added to the data to make the
sum of all the digits of the binary data either always even (even parity) or always odd (odd par-
ity).
path 1. The logical sequence of instructions executed by a computer.
2. The flow of an electrical signal through a circuit.
pending interrupts An interrupt that has been triggered but has not been serviced, either because the processor is
busy servicing another interrupt or global interrupts are disabled.
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