CHAPTER 5 BBR
Preliminary User's Manual A14874EJ3V0UM
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5.1 Programmable Peripheral I/O Area
The NU85E has a 4 KB peripheral I/O area that is allocated in advance in the address space and a 12 KB
programmable peripheral I/O area that can be allocated at arbitrary addresses according to register settings (See
4.4
Programmable Peripheral I/O Area Selection Function
).
If the peripheral I/O area or programmable peripheral I/O area in the memory map shown in Figure 5-3 is
accessed, the NPB becomes active.
The programmable peripheral I/O area is set by the peripheral I/O area select control register (BPC).
Figure 5-3. Peripheral I/O Area and Programmable Peripheral I/O Area
(a) 64 MB mode
(b) 256 MB mode
(n = yy11B)
Peripheral I/O area
(4 KB)
(4 KB)
Programmable
peripheral I/O area
(12 KB)
FFFFFFFH
FFFF000H
FFFEFFFH
0000000H
xxxnFFFH
xxxm000H
3FFF000H
3FFEFFFH
3FFFFFFH
3FFF000H
3FFEFFFH
xxxnFFFH
xxxm000H
0000000H
Same
area
(m = yy00B)
Same
area
Same
area
Note
Peripheral I/O area
(4 KB)
(4 KB)
Programmable
peripheral I/O area
(12 KB)
(RAM area)
(n = yy11B)
(m = yy00B)
Note
See
Figure 3-8 Data Area (256 MB Mode)
.
Remarks 1.
xxx: Setting according to the PA13 to PA02 bits of the BPC register
yy: Setting according to the PA01 and PA00 bits of the BPC register
2.
Since the areas indicated by “same area” are linked, if data is written in one area, data having
the same contents is also written in the other area.