
2-37
3802 GROUP USER’S MANUAL
APPLICATION
2.3 Serial I/O
Fig. 2.3.22 Control procedure at a receiving side [Communication using a clock synchronous
serial I/O]
Pass 2 ms
RESET
Initialization
.
SIO1CON (Address : 1A
16
)
1111
X
11
X
2
TB/RB (Address : 18
16
)
Dummy data
S
RDY1
output
S
RDY1
signal is output by writing data to
the TB/RB.
Using the
S
RDY1
, the transmit enabled bit
(bit4) of the SIO1CON is set to “1.”
An interval of 2 ms is generated by a timer.
Y
N
Check a completion of receiving
(Receive buffer full flag)
SIO1STS (Address : 19
16
), bit1
1
0
Read out reception data from
TB/RB (Address : 18
16
)
Receive the first byte data.
A Receive buffer full flag is set to “0” by reading data.
Check a completion of receiving
(Receive buffer full flag)
SIO1STS (Address : 19
16
), bit1
1
0
Read out reception data from
TB/RB (Address : 18
16
)
Receive the second byte data.
A Receive buffer full flag is set to “0” by reading data.
X
: This bit is not used in this application.
Set it to “0” or “1.” It’s value can be disregarded.
G