2-33
3802 GROUP USER’S MANUAL
APPLICATION
2.3 Serial I/O
2.3.5 Serial I/O application examples
(1) Communication using a clock synchronous serial I/O (transmit/receive)
Outline :
2-byte data is transmitted and received through the clock synchronous serial I/O. The
RDY
signal is used for communication control.
_____
Figure 2.3.17 shows a connection diagram, and Figure 2.3.18 shows a timing chart.
Fig. 2.3.17 Connection diagram [Communication using a clock synchronous serial I/O]
Specifications :
The Serial I/O1 is used (clock synchronous serial I/O is selected)
Synchronous clock frequency : 125 kHz (f(X
IN
) = 4 MHz is divided by 32)
The
S
RDY1
(receivable signal) is used.
The receiving side outputs the
S
RDY1
signal at intervals of 2 ms (generated by
timer), and 2-byte data is transferred from the transmitting side to the receiving
side.
Fig. 2.3.18 Timing chart [Communication using a clock synchronous serial I/O]
D
0
D
4
D
2
D
1
D
6
D
5
D
7
D
3
D
0
D
4
D
2
D
1
D
6
D
5
D
7
D
3
D
0
D
1
T
X
D
S
CLK1
S
RDY1
2 ms
P4
1
/
INT
0
S
CLK1
T
X
D
3802 group
S
RDY1
S
CLK
R
X
D
3802 group
Transmitting side
Receiving side