External Access - Fujitsu FR60 Hardware Manual

4.4.4

External Access

This section describes the relationship between the internal register and external data
bus based on the byte ordering (endian method) and the bus width.
■ Word Access
External access using word access is shown below:
16-bit bus
width
D31
D00
8-bit bus
width
Internal
D31
D00
Big endian mode
Internal External
Reg terminal
address: "0" "2"
D31
AA AA CC
BB BB DD
D16
CC
DD
(1) (2)
External
Reg terminal
address:
"0" "1" "2" "3"
D31
AA AA BB CC DD
D24
BB
CC
DD
(1) (2) (3) (4)
Control
Internal
terminal
Reg
D31
WR0
WR1
D00
Internal
Control
Reg
terminal
address:
D31
WR0
AA
BB
CC
DD
D00
Little endian mode
External
terminal
address: "0" "2"
D31
AA DD BB
BB CC AA
D16 D1 6
CC
DD
(1) (2)
External
terminal
"0" "1" "2" "3"
D31
DD CC BB AA
D24
(1) (2) (3) (4)
Control
terminal
WR0
WR1
Control
terminal
WR0
201