Intel 8XC251SA, User Manual

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8XC251SA, SB, SP, SQ USER’S MANUAL
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3.2.3 External Memory
Regions 01:, FE:, and portions of regions 00: and FF: of the memory space are implemented as
external memory (Figure 3-5 on page 3-7). For discussions of external memory see “Configuring
the External Memory Interface” on page 4-8 and Chapter 13, “External Memory Interface.”
3.3 8XC251SA, SB, SP, SQ REGISTER FILE
The 8XC251Sx register file consists of 40 locations: 0–31 and 56–63, as shown in Figure 3-6.
These locations are accessible as bytes, words, and dwords, as described in “Byte, Word, and
Dword Registers” on page 3-13. Several locations are dedicated to special registers (see “Dedi-
cated Registers” on page 3-13); the others are general-purpose registers.