37
3.5 Data Construction
The data allocation of the FR20 series uses as follow.
• Bit ordering: Little endian
• Byte ordering: Big endian
■ Bit Ordering
In the FR20 series, the little endian has been adopted as a bit ordering.
Figure 3.5-1 shows the data allocation of the bit ordering.
Figure 3.5-1 Data allocation of bit ordering
■ Byte Ordering
Big endian is adopted as the byte ordering for the FR family.
Figure 3.5-2 shows the data allocation of the byte ordering.
Figure 3.5-2 Data allocation of byte ordering
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
LS
B
MSB
bit
MSB LSB
Memory bitNo.31 23 15 7 0
bit
70
10101010 11001100 11111111 00010001
n address 10101010
(n+1) address 11001100
(n+2) address 11111111
(n+3) address 00010001