[Home] [This version is outdated, a new version is here]
*Title...
*Search:...
*Read Me/FAQ/General Info...
*_IBM...
*ACC Micro...
*ALD...
*ALi...
*AMD . . . . . . . [no datasheets, some info]...
*Chips & Technologies...
*Contaq  . . . . . [no datasheets, some info]...
*Efar Microsystems [no datasheets, some info]...
*ETEQ...
*Faraday...
*Forex . . . . . . [List only, no datasheets found]...
*Intel...
**82360SL     I/O Subsystem                                   10/05/90
***Notes:...
***Info:
The  82360SL Peripheral  I/O  contains dedicated  logic  to perform  a
number of  CPU, memory, and peripheral support  functions. The 82360SL
device also contains an extensive set of programmable power management
facilities  which  allow  minimized  system  energy  requirements  for
battery-powered portable computers.

The  82360SL includes  a  complete set  of  on-chip peripheral  device
functions  including  two 16450  compatible  serial  ports, one  8-bit
Centronics interface  or bi-directional parallel port,  two 8254 comp-
atible timer counters, two  8259 compatible interrupt controllers, two
8237  compatible  DMA controllers,  one  74LS612  compatible DMA  page
register,  one  146818  compatible  Real-time clock/calendar  with  an
additional  128 bytes  of battery  backed CMOS  RAM and  an integrated
drive electronics (IDE) hard  disk drive interface.  The Intel 82360SL
also contains highly programmable chip selects and complete peripheral
interface  logic  for  direct  keyboard  and  floppy  disk  controller
support. The peripheral registers  and functions behave exactly as the
discrete  components  commonly  found  in industry  standard  personal
computers. The  peripheral logic is  enhanced for static  operation by
supporting write only registers as read/write.

The processor  and memory support  functions contained in  the 82360SL
device eliminate  most of the external random-logic  "glue" that might
otherwise   be  required.   The  82360SL   device   provides  internal
programmable-frequency clock generators for the ISA bus backplane, and
video subsystems. A programmable, low-power DRAM refresh timer is also
provided to  maintain system memory integrity during  the power saving
suspend state.

The  82360SL also  contains a  flexible set  of hardware  functions to
support  the  growing   sophistication  in  power  management  schemes
required by portable systems. Numerous hardware timers, event monitors
and  I/O  interfaces  can  programmable  monitor  and  control  system
activity.  Firmware developed  by  the system  designer allocates  and
directs the hardware to fulfill the unique power management needs of a
given system configuration.

All of the standard  peripheral registers, clock-generation logic, and
power-management  facilities  have been  designed  to ensure  complete
compatibility  with   existing  operating  systems   and  applications
software.
***Versions:...
***Features:...
**82370       Integrated System Peripheral (for 82376)         c:Oct88...
**82371FB/SB  PCI ISA IDE Xcelerator 82371FB/82371SB (PIIX/3) 01/31/95...
**82371MX     Mobile PCI I/O IDE Xcelerator (MPIIX)           11/01/95...
**82371AB     PCI-TO-ISA / IDE Xcelerator 82371AB (PIIX4)     02/17/97...
**82374/82375 PCI-EISA Bridge (82374EB/82375EB, 374SB/375SB)   c:Mar93...
**82378       System I/O (SIO) (82378IB and 82378ZB)           c:Mar93...
**82379AB     System I/O-APIC (SIO.A)                           <Dec94...
**82380       32-bit DMA Controller w/ Integrated Peripherals 02/01/87...
**82380FB/AB  PCIset: 82380FB Mobile PCI-to-PCI Bridge(MPCI2) 02/17/97...
**82384       Clock Generator and Reset Interface                  c86...
**82385       32-bit Cache Controller for 80386               09/29/87...
**82385SX     32-bit Cache Controller for 80386SX             01/25/89
***Notes:...
***Info:
The  82385SX Cache  Controller is  a high  performance  peripheral for
Intel's 386 SX Microprocessor. It stores a copy of frequently accessed
code  and data  from main  memory  in a  zero wait  state local  cache
memory. The 82385SX  allows the 386 SX Microprocessor  to run near its
full potential  by reducing the average  number of CPU  wait states to
nearly zero.   The dual bus  architecture of the 82385SX  allows other
masters  to access  system resources  while  the 386  SX CPU  operates
locally  out of  its cache.   In  this situation,  the 82385SX's  "bus
watching" mechanism preserves cache coherency by monitoring the system
bus address lines at no cost to system or local throughput.

The  82385SX  is   completely  software  transparent,  protecting  the
integrity of system software. High performance and board space savings
are achieved because the 82385SX  integrates a cache directory and all
cache management logic on one chip.

1.0 82385SX FUNCTIONAL OVERVIEW
The  82385SX Cache  Controller is  a high  performance  peripheral for
Intel's 386  SX microprocessor.  This chapter provides  an overview of
the 82385SX, and  of the basic architecture and operation  of a 386 SX
CPU/ 82385SX system.

1.1 82385 OVERVIEW

The main  function of a cache  memory system is to  provide fast local
storage  for frequently  accessed  code and  data.   The cache  system
intercepts  386 SX  memory  references  to see  if  the required  data
resides in the cache. If the data  resides in the cache (a hit), it is
returned to the  386 SX without incurring wait states.  If the data is
not cached (a miss), the reference  is forwarded to the system and the
data retrieved from main memory.  An efficient cache will yield a high
"hit rate"  (the ratio of cache  hits to total 386  SX accesses), such
that the majority of accesses  are serviced with zero wait states. The
net effect is that the wait states incurred in a relatively infrequent
miss are  averaged over  a large number  of accesses, resulting  in an
average of  nearly zero wait states  per access. Since  cache hits are
serviced locally, a  processor operating out of its  local cache has a
much  lower  "bus  utilization"  which reduces  system  bus  bandwidth
requirements, making more bandwidth available to other bus masters.

The  82385SX Cache  Controller integrates  a cache  directory  and all
cache  management  logic required  to  support  an  external 16  Kbyte
cache. The cache directory structure  is such that the entire physical
address range  of the 386  SX is mapped  into the cache.  Provision is
made to  allow areas of memory  to be set aside  a non-cacheable.  The
user has two  cache organization options: direct mapped  and 2-way set
associative.   Both provide  the high  hit rates  necessary to  make a
large, relatively slow  main memory array look like  a fast, zero wait
state memory to the 386 SX.

A  good hit  rate is  an essential  ingredient of  a  successful cache
implementation. Hit rate  is the measure, of how  efficient a cache is
in maintaining a copy of  the most frequently requested code and data.
However,   efficiency  is   not  the   only  factor   for  performance
consideration.  Just as essential are sound cache management policies.
These policies refer to the handling of 386 SX writes, preservation of
cache  coherency, and ease  of system  design.  The  82385SX's "posted
write"  capability allows  the majority  of 386  SX  writes, including
non-cacheable, to  run with zero  wait states, and the  82385SX's "bus
watching" mechanism preserves cache coherency with no impact on system
performance.  Physically, the 82385SX ties directly to the 386 SX with
virtually no external logiC.

***Versions:...
***Features:...
**82395DX     High Performance Smart Cache                    06/18/90...
**82395SX     Smart Cache                                     12/17/90...
**82396SX     Smart Cache                                     12/17/90...
**82485       Turbo Cache (and 485Turbocache)                      c90...
**82489DX       Advanced Programmable Interrupt Controller    10/12/92...
**82495DX/490DX DX CPU-Cache Chip Set                           <Sep91...
**82495XP/490XP Cache Controller / Cache RAM (for i860)       06/05/91...
**82496/491     Cache Controller / Cache RAM (for P5 Pentium) 03/22/93...
**82497/492   Cache Controller / Cache RAM (for P54 Pentium)    <Nov94...
**82498/493   Cache Controller / Cache RAM (for P54 Pentium)    <Nov94...
**
**Later chipsets (basic spec):
**440 series:...
**450NX  (?)            06/29/98:...
**?????  (Profusion)    c:99...
**800 series...
*Headland/G2...
*HMC (Hulon Microelectronics)...
*Logicstar...
*Motorola...
*OPTi...
*PC CHIPS/Amptron/Atrend/ECS/Elpina/etc...
*SIS...
*Symphony...
*TI (Texas Instruments)...
*UMC...
*Unresearched:...
*VIA...
*VLSI...
*Western Digital...
*Winbond...
*ZyMOS...
*General Sources:...

(c) Copyright mR_Slugs Warehouse - All rights Reserved