UDC920BE串行模块,ABB使用在哪里
MPC750处理器PowerPC 750是一个32位微处理器，其32KB片上缓存由32KB/32KB一级缓存组成。二级缓存和16位1MB闪存位于MVME2700基板上。16MB至256MB ECC DRAM和4MB或8MB额外（64位）闪存内存位于RAM200内存夹层上。Raven桥接器控制器ASIC提供了PowerPC微处理器总线和PCI本地总线。电气方面Raven芯片是64位PCI连接。
UDC920BE串行模块四个可编程地图解码器在每个方向上，在PowerPC之间提供灵活的寻址微处理器总线和PCI本地总线。
闪存MVME2700基板提供1MB 16位闪存内存位于两个8位插槽中。RAM200内存夹层可容纳4MB或8MB额外的64位闪存板上的监视器/调试器PPCBug固件驻留在闪存中炸薯条PPCBug提供以下功能：❏ 引导和重置系统❏ 初始化请求
❏ 显示和修改配置变量❏ 运行自检和诊断
❏ 更新固件ROM跳线头（J9）告诉Falcon芯片组在内存中的取数位置电路板重置向量。根据J9的配置，重置从闪存组A（64位闪存）或B执行（16位闪存）。
在正常操作中，闪存设备处于“只读”模式内容是预定义的，可以防止意外写入由于断电情况。然而，为了便于编程，编程电压持续提供给设备；你可以只需执行适当的程序即可修改Flash内容命令序列。请参阅第三方数据表和/或PPCBug固件包用户手册，了解更多特定于设备的信息有关修改Flash内容的信息。RAM200内存模块RAM200是ECC DRAM内存夹层模块（连同LED夹层和可选PCI夹层卡）插入基板，形成完整的MVME2700单板计算机
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.
