Mylex MPE-PNTM, User Manual

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256K--512K of Write--Back Cache Memory (Sec-
ondary Cache): Cache memory is an essential part
of maintaining high system performance.
In most
cases, the larger the cache memory, the greater the
system performance. Repetitive programs such as
spread--sheet and CAD applications will benefit the
most. The standard configuration does not include
Cache memory. To allow easy upgrade of cache mem-
ory, the SRAM module is used, allowing 256K/512K of
cache using standard or burst SRAMs.
Unlike other cache architectures that require the CPU
to write directly to DRAM, the write--back cache is the
most efficient way for cache to write information back
to main memory. This is because the cache can be
written to faster than DRAM. Then the cache circuit
writes the information to the DRAM by itself. The sec-
ondary cache can be set up to operate in write--back
or write--through mode.
Embedded I/O: The MPE--PNTM includes the latest
generation of Super I/O controllers which provides 2
serial ports, a parallel port, IDE disk interface and
floppy disk controller. The floppy disk controller is ca-
pable of supporting the new “4MB” floppy disk drives.
Just as important, the floppy controller is capable of
data rates of 1MB/sec--—this is a significant benefit in
performance on various floppy tape drives compatible
with the 1MB/sec transfer rates. In addition, the serial
port UARTS are compatible with the National™ 16550
with 16--byte FIFO.
FLASH ROM BIOS: At one time or another, the need
can arise to update the system BIOS. Usually this
means that the system must be partially disassem-
bled, the old ROM chip removed, discarded, the new
ROM chip installed and the system reassembled.
With FLASH technology, BIOS updates are made sim-
ply by running a program. With the MPE--PNTM there
are no chassis to open, no jumpers to set. Simply run
a DOS program that reads a BIOS binary image file
and then programs the new BIOS into the FLASH
memory chip.
1 - 4 Version D02 Copyright 1994
MPE-PNTM System Board Introduction