OCPRF100 MP Server System Technical Product Specification

Revision 1.0

A description of each memory block is provided, showing the purpose and function as determined by microcontroller programming. These functions may also be controlled by system software using SCSI commands defined in the SAF-TE specification.

Figure 8-4: Microcontroller Memory Map

8.6.1.1Flash Memory Region (0x0000 – 0x7FFF)

The Atmel* 27C257 or equivalent Flash EPROM is accessible as either a data or program memory read. Writes to Flash are also allowed in order to support field-upgradeable code. The lower 4KB (0x0000 – 0x0fff) are not writeable unless the boot block write protect bit in the fan mux register is cleared.

8.6.1.2Static RAM Region (0x8000 – 0xF7FF)

The static RAM is accessible as either data or program accesses. It is possible to load executable code into the static RAM and execute directly from RAM.

8.6.1.3Memory Mapped Registers (0xF800 – 0xFFFF)

The upper 2KB of the controller address space are mapped to eight regions of 256 bytes for memory-mapped registers and miscellaneous functions. For each of the regions listed, the actual function occupies less than the full 256 bytes of its address decode. Unless specifically stated,

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