NEC V850E/Dx3, Preliminary User'S Manual

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Chapter 7 Bus and Memory Control (BCU, MEMC)
Preliminary User’s Manual U17566EE1V2UM00
7.8 Data Access Order
7.8.1 Access to 8-bit data busses
This section shows how byte, half word and word accesses are performed for
an 8-bit data bus.
(1) Byte access (8 bits)
(a) Little endian
Figure 7-21 Left: Access to even address (2n)
Right: Access to odd address (2n + 1)
(b) Big endian
Figure 7-22 Left: Access to even address (2n)
Right: Access to odd address (2n + 1)
7
0
7
0
Byte data External
data bus
2n
Address
7
0
7
0
Byte data External
data bus
2n + 1
Address
7
0
7
0
Byte data External
data bus
2n
Address
7
0
7
0
Byte data External
data bus
2n + 1
Address
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