Sun Microsystems SPARCstation 4, Service Manual

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Glossary-2 SPARCstation 4/Xterminal 1 Service Manual • January 1995
CRU Customer-replaceable unit.
DMA Direct memory access.
DRAM Dynamic random access memory.
DSIMM DRAM single in-line memory module. A small printed circuit card that
contains dynamic random access memory (DRAM) chips.
Ecache External cache. Cache that is located external to the microprocessor.
See also cache.
FORTH A high-level programming language. A major feature of FORTH is that
user-defined operators can be used as if they were primitives.
FORTH Toolkit An interactive command interpreter based on the FORTH programming
language. While in the Toolkit, you will see the
ok
prompt. The Toolkit gives
you access to an extensive set of functions for performing fault isolation and
debugging.
frame buffer board A printed circuit board installed in an SBus slot of the system unit that controls
a video display.
FRU Field-replaceable unit.
IC Integrated circuit.
ID Identification.
I/O Input/output. A device that inputs data to a computer CPU and receives data
from a computer CPU. Examples of I/O devices include keyboards, mice,
monitors, and peripherals devices.
IU Integer unit.
LANCE Local-area network controller for Ethernet.
LED Light-emitting diode.
Location See address.
MBus module A printed circuit board installed in an MBus slot of the system unit that
contained the CPU circuitry and components.
Monitor (1) Indicated by the
>
prompt. From the
>
prompt, you can boot the system,
continue the execution of a halted program, or enter the FORTH Toolkit.
Monitor (2) A video display unit that is part of the SPARCstation 4 or SPARC Xterminal 1
system. It is not synonymous with terminal.
MMU Memory management unit.
NVRAM Nonvolatile RAM.