Motorola APX 2000, Detailed Service Manual

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Glossary-8 Glossary
SRAM See static RAM.
SSI See Synchronous Serial Interface.
Standby mode An operating mode in which the radio is muted but still continues to
monitor data.
static RAM A type of memory used for volatile, program/data memory that does not
need to be refreshed.
Synchronous Serial
Interface DSP interface to peripherals that consists of a clock signal line, a frame
synchronization signal line, and a data line.
system central
controllers Main control unit of the trunked dispatch system; handles ISW and
OSW messages to and from subscriber units
(See ISW and OSW) .
system select The act of selecting the desired operating system with the system-select
switch (also, the name given to this switch).
thin small-outline
package A type of dynamic random-access memory (DRAM) package that is
commonly used in memory applications.
time-out timer A timer that limits the length of a transmission.
TOT See time-out timer.
transceiver Transmitter-receiver. A device that both transmits and receives analog
or digital signals. Also abbreviated as XCVR.
transmitter Electronic equipment that generates and amplifies an RF carrier signal,
modulates the signal, and then radiates it into space.
TSOP See thin small-outline package.
TX Transmit.
UART See also Universal Asynchronous Receiver Transmitter.
UHF Ultra-High Frequency.
Universal
Asynchronous
Receiver Transmitter A microchip with programming that controls a computer's interface to its
attached serial devices.
Universal Connector Interface point for all accessories to the radio.
Universal Serial Bus An external bus standard that supports data transfer rates of 12 Mbps.
USB See Universal Serial Bus.
VCO See voltage-controlled oscillator.
VCOB IC Voltage-Controlled Oscillator Buffer IC.
Term Definition