Data Structure; Figure 2.4-1 Data Mapping In Bit Ordering Mode; Figure 2.4-2 Data Mapping In Byte Ordering Mode - Fujitsu MB91F109 FR30 Hardware Manual

CHAPTER 2 CPU
2.4

Data Structure

FR-series data is mapped as follows:
• Bit ordering: Little endian
• Byte ordering: Big endian
Bit Ordering
The FR series uses little endian for bit ordering.
Figure 2.4.1 shows data mapping in bit ordering mode.
bit 31
30
MSB
Byte Ordering
The FR series uses big endian for byte ordering.
Figure 2.4.2 shows data mapping in byte ordering mode.
Address n
Address (n+1)
Address (n+2)
Address (n+3)
42

Figure 2.4-1 Data Mapping in Bit Ordering Mode

29 27 25 23 21
28 26 24 22 20

Figure 2.4-2 Data Mapping in Byte Ordering Mode

Memory
bit
7 0
10101010
11001100
11111111
00010001
19 17 15 13 11
18 16 14 12 10
MSB
bit31 23
10101010 11001100
9 7 5 3 1
8 6 4 2 0
LSB
15 7
11111111 00010001
LSB
0