Motorola MVME177P, Инструкция по установке и эксплуатации

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Functional Description
4
Memory Options
The following memory options are available on the different versions of
MVME177P boards.
DRAM
MVME177P boards are built with 16MB, 32MB, 64MB, or 128MB
synchronous DRAM (SDRAM). The MVME177P may have the SDRAM
configured to model 4MB, 8MB, 16MB, 32MB, 64MB, or 128MB of
ECC-protected DRAM.
The SDRAM memory array itself is always a single-bit error correcting
and multi-bit error detection memory, irrespective of which interface
model you use to access the SDRAM.
For specifics on SDRAM performance and for detailed programming
information, refer to the chapters on MCECC memory controller
emulations in the MVME1X7P Single Board Computer Programmer’s
Reference Guide.
SRAM
The MVME177P implementation includes 128KB SRAM (static RAM).
SRAM architecture is single non-interleaved. SRAM performance is
described in the section on the SRAM memory interface in the
MVME1X7P Single Board Computer Programmer’s Reference Guide.
Battery backup options are selected via jumper header J9.
EPROMs
There are two 44-pin PLCC/CLCC EPROM sockets for SGS-Thompson
M27C4002 (256K x 16) or AMD 27C4096 type EPROMs. They are
organized as one 32-bit wide bank that supports 8-, 16-, and 32-bit read
accesses.
The EPROMs as shipped are normally used for the onboard debugger
firmware (177Bug), but can be used to download user code to Flash. The
EPROMs may occupy 2MB of memory over two banks. The second bank
can be used as 2MB of Flash memory in mixed mode. The EPROMs
occupy only 1MB in the ROM space in mixed mode and are repeated in