NEC POWERMATE P - SERVICE MANUAL 1995, Инструкция по обслуживанию и справочник, Страница: 20 / 171

Technical Information 1-5
Table 1-1 System Board Chips
Chip Description
Intel 28F100BXT 1 Mb component 128k x 8 Flash ROM (128 KB)
Socketed 3V lithium coin cell battery
Can be replaced by Sanyo CR2032
coin cell battery or equivalent
Real-time clock battery for integrated RTC on
PC87306
Vibra 16S (CT2504) (multimedia
systems only) Multimedia codec (digital audio and analog
mixing chip)
Yamaha OPL3-L Synthesizer Chip
(multimedia systems only) Frequency modulated synthesizer
Processor
The PowerMate P series of computers use the following Pentium processors:
n
PowerMate P120 — 120-MHz processor with internal speed of 120 MHz and
external speed of 60 MHz
n
PowerMate P130 — 133-MHz processor with internal speed of 133 MHz and
external speed of 66 MHz.
Each processor has 16 KB of write-back primary cache and a math coprocessor. The 16 KB
primary cache provides 8 KB for instructions and 8 KB for data.
The processor is an advanced pipelined 32-bit addressing, 64-bit data processor designed to
optimize multitasking operating systems. The 64-bit registers and data paths support 64-bit
addresses and data types.
To use the Pentium processor’s power, the system features an optimized 64-bit memory
interface and complementary asynchronous pipelined 256-KB secondary cache.
The processor is compatible with 8-, 16-, and 32-bit software written for the Intel386™,
Intel486™, and Pentium processors.
To accommodate future technologies and work requirements, the Pentium processor comes
in a 320-pin zero insertion force (ZIF) socket. The socket provides an upgrade path to the
next generation processor.
Secondary Cache
The system board contains 256 KB of secondary cache, external to the processor. The
cache uses 15-ns SRAM that allows data to be sent or received from cache with one wait
state burst. Cache memory improves read performance by holding copies of code and data
that are frequently requested from the system memory by the processor. Cache memory is
not considered part of the expansion memory.