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Bus and Memory Control (BCU, MEMC)
Chapter 7
Preliminary User’s Manual U17566EE1V2UM00
(4)
BEC - Endian configuration register
The 16-bit BEC register defines the endian format in which word data in the
memory is processed. Each chip select area is controlled separately.
Access
This register can be read/written in 16-bit units.
Address
FFFF F068
H
Initial Value
0000
H
This register must be initialized as described in
Table 7-16
and
Table 7-17
.
Caution
1.
The bits marked with 0 must always be 0.
2.
To initialize an external memory area after a reset, register BEC has to be
set. Do not change this register after initialization. Do not access external
devices before initialization is finished.
Note
1.
Accesses to all internal resources are fixed to little endian format.
2.
Different chip select signals can be active for the same memory bank. The
priority order defines, which chip select signal is valid.
3.
Set the chip select area which is specified as the programmable peripheral
I/O area to little endian format.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
BE70
0
BE60
0
BE50
0
BE40
0
BE30
0
BE20
0
BE10
0
BE00
CS7
CS6
CS5
CS4
CS3
CS2
CS1
CS0
Table 7-15
BEC register contents
Bit Position
Bit Name
Function
14, 12, 10,
8, 6, 4, 0
BEk0
Sets the endian format for processing of word data for each chip select area.
0: Little endian
1: Big endian
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