UDC920BE串行模塊,ABB使用在哪里
MPC750處理器PowerPC 750是一個32位微處理器，其32KB片上緩存由32KB/32KB一級緩存組成。二級緩存和16位1MB閃存位于MVME2700基板上。16MB至256MB ECC DRAM和4MB或8MB額外（64位）閃存內(nèi)存位于RAM200內(nèi)存夾層上。Raven橋接器控制器ASIC提供了PowerPC微處理器總線和PCI本地總線。電氣方面Raven芯片是64位PCI連接。
UDC920BE串行模塊四個可編程地圖解碼器在每個方向上，在PowerPC之間提供靈活的尋址微處理器總線和PCI本地總線。
閃存MVME2700基板提供1MB 16位閃存內(nèi)存位于兩個8位插槽中。RAM200內(nèi)存夾層可容納4MB或8MB額外的64位閃存板上的監(jiān)視器/調(diào)試器PPCBug固件駐留在閃存中炸薯條PPCBug提供以下功能：? 引導(dǎo)和重置系統(tǒng)? 初始化請求
? 顯示和修改配置變量? 運行自檢和診斷
? 更新固件ROM跳線頭（J9）告訴Falcon芯片組在內(nèi)存中的取數(shù)位置電路板重置向量。根據(jù)J9的配置，重置從閃存組A（64位閃存）或B執(zhí)行（16位閃存）。
在正常操作中，閃存設(shè)備處于“只讀”模式內(nèi)容是預(yù)定義的，可以防止意外寫入由于斷電情況。然而，為了便于編程，編程電壓持續(xù)提供給設(shè)備；你可以只需執(zhí)行適當(dāng)?shù)某绦蚣纯尚薷腇lash內(nèi)容命令序列。請參閱第三方數(shù)據(jù)表和/或PPCBug固件包用戶手冊，了解更多特定于設(shè)備的信息有關(guān)修改Flash內(nèi)容的信息。RAM200內(nèi)存模塊RAM200是ECC DRAM內(nèi)存夾層模塊（連同LED夾層和可選PCI夾層卡）插入基板，形成完整的MVME2700單板計算機
MPC750 Processor
The PowerPC 750 is a 32-bit microprocessor whose 32KB on-chip cache
is composed of 32KB/32KB L1 cache. The L2 cache and 1MB of 16-bit
Flash memory reside on the MVME2700 base board. The 16MB to
256MB ECC DRAM and 4MB or 8MB of additional (64-bit) Flash
memory are located on the RAM200 memory mezzanine.
The Raven bridge controller ASIC provides the bridge between the
PowerPC microprocessor bus and the PCI local bus. Electrically, the
Raven chip is a 64-bit PCI connection. Four programmable map decoders
in each direction provide flexible addressing between the PowerPC
microprocessor bus and the PCI local bus.
Flash Memory
The MVME2700 base board has provision for 1MB of 16-bit Flash
memory in two 8-bit sockets. The RAM200 memory mezzanine
accommodates 4MB or 8MB of additional 64-bit Flash memoryThe onboard monitor/debugger, the PPCBug firmware, resides in the Flash
chips. PPCBug provides functionality for:
? Booting and resetting the system
? Initializing a request
? Displaying and modifying configuration variables
? Running self-tests and diagnostics
? Updating firmware ROM
A jumper header (J9) tells the Falcon chip set where in memory to fetch
the board reset vector. Depending on the configuration of J9, resets
execute either from Flash memory bank A (64-bit Flash) or from bank B
(16-bit Flash).
In normal operation the Flash devices are in “read-only” mode, their
contents are predefined, and they are protected against inadvertent writes
due to loss of power conditions. For ease in programming, however,
programming voltage is continuously supplied to the devices; you can
modify the Flash contents by simply executing the proper program
command sequence. Refer to the third-party data sheet and/or to the
PPCBug Firmware Package User’s Manual for further device-specific
information on modifying Flash contents.
RAM200 Memory Module
The RAM200 is the ECC DRAM memory mezzanine module that
(together with an LED mezzanine and an optional PCI mezzanine card)
plugs into the base board to make a complete MVME2700 single board
computer.
