Renesas 4514 - Manual (Page 145)

APPLICATION
2.4 Serial I/O
2-42 4513/4514 Group User’s Manual
2.4.3 Operation description
Figure 2.4.2 shows the serial I/O connection example, Figure 2.4.3 shows the serial I/O register state, and
Figure 2.4.4 shows the serial I/O transfer timing.
Fig. 2.4.2 Serial I/O connection example
Fig. 2.4.3 Serial I/O register state when transmitting/receiving
S
7
S
6
S
5
S
4
S
3
S
2
S
1
S
0
M 7 M 6 M 5 M 4 M 2 M 3 M 1 M 0
Master (M 7 –M 0 : Transfer data)
Serial I/O register (SI)
S IN pin
S IN pin S OUT pin
S OUT pin
Slave (S 7 –S 0 : Transfer data)
Serial I/O register (SI)
M
7
M
6
M
5
M
4
M
2
M
3
M
1
M
0
M 6 M 5 M 4 M 2 M 3 M 1
M
6
M
5
M
4
M
2
M
3
M
1
S
0
M 7
M 7
M
6
M
5
M
4
M
2
M
3
S
0
M
7
S
7
S
6
S
5
S
4
S
3
S
2
S
1
S
0
S 7 S 6 S 5 S 4 S 3 S 2 S 1 S 0
S
7
S
6
S
5
S
4
S
3
S
2
S
1
S 7 S 6 S 5 S 4 S 3 S 2 S 1 M 0
S 7 S 6 S 5 S 4 S 3 S 2 M 0
M
7
M
6
M
5
M
4
M
2
M
3
M
1
M
0
Transfer data setting
Transfer starts
Falling of clock
Rising of clock
Falling of clock
Transfer completes
∗
∗
∗
∗
S OUT
S CK
S IN
D 5
S CK
S OUT
S IN
D 5
4513/4514 4513/4514
Master (internal clock selected) Slave (external clock selected)
Control signal
Note: The control signal is used to inform the master by the pin level
that the slave is in a ready state to receive.
The 4513/4514 Group does not have a control pin exclusively
used for serial I/O.
Accordingly, if a control signal is required, use the normal input/output ports.