ST10R272L - MEMORY ORGANIZATION
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Segments are contiguous blocks of 64KBytes. They are referenced via the code segment
pointer CSP for code fetches, and via an explicit segment number for data accesses when
overriding the standard DPP scheme.
During code fetching, segments are not changed automatically, but must be switched
explicitly. Instructions JMPS, CALLS and RETS will do this.
Note
To prevent the prefetcher from trying to leave the current segment (in larger
sequential programs), make sure that the highest used code-location of a segment,
contains an unconditional branch instruction to the respective following segment.
Data Pages are contiguous blocks of 16KByte each. They are referenced via the data page
pointers DPP3...0 and via an explicit data page number for data accesses when overriding
the standard DPP scheme. Each DPP register can select one of the possible 1024 data
pages. The DPP register, used for the current access, is selected via the two upper bits of
the 16-bit data address. Subsequent 16-bit data addresses that cross the 16KByte data
page boundaries, use different data page pointers while the physical locations need not be
subsequent within memory.
