Motorola ASTRO MT 1500, Service Manual

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Glossary Glossary
Term Definition
A/D Analog-to-Digital converter; converts an instantaneous dc voltage
level to a corresponding digital value.
ABACUS IC Custom integrated circuit providing a digital receiver intermediate
frequency (IF) backend.
ALC A utomatic L evel C ontrol; a circuit in the transmit RF path that controls
RF power amplifier output, provides leveling over frequency and
voltage, and protects against high VSWR.
CODEC CO der/ DEC oder.
D/A D igital-to- A nalog converter; converts a digital value to a corresponding
dc voltage value.
DSP D igital S ignal P rocessor. A microcontroller specifically tailored for signal
processing computations.
DSP Code D igital S ignal P rocessor Code ; object code executed by the Digital
Signal Processor in an ASTRO XTS 2500/XTS 2500 I subscriber radio.
The DSP is responsible for computation-intensive tasks, such as
decoding ASTRO signaling.
Firmware Code executed by an embedded processor such as the Host or DSP in
a subscriber radio. This type of code is typically resident in non-volatile
memory and as such is more difficult to change than code executed
from RAM.
FGU F requency G eneration U nit. This unit generates ultra-stable, low-phase
noise master clock and other derived synchronization clocks that are
distributed throughout the communication network.
FLASHcode A 13-digit code which uniquely identifies the System Software Package
and Software Revenue Options that are enabled in a particular
subscriber radio. FLASHcodes are only applicable for radios which are
upgradeable through the FLASHport process.
FLASHport™ A Motorola term that describes the ability of a radio to change memory.
Every FLASHport radio contains a FLASHport EEPROM memory chip
that can be software written and rewritten to, again and again.
FracN A Motorola-proprietary, CMOS fractional-N frequency synthesizer with
built-in dual-port modulation.
Host The Motorola microcontroller unit.