
38B7 Group User’s Manual
APPLICATION
2-79
2.3 Serial I/O
Figure 2.3.56 shows a control procedure of the transmission side, and Figure 2.3.57 shows a control
procedure of the reception side.
Fig. 2.3.56 Control procedure of transmission side
SIO2STS (address 001E16), bit0?
RESET
Communication completion
(address 001D16)
(address 003816)
(address 003716)
(address 000E16), bit6
(address 000F16), bit6
P7 (address 000E16), bit6
1
10 ms has passed ?
Y
N
TB/RB (address 001F16)
The second byte of
a transmission data
1
0
SIO2STS (address 001E16), bit2?
1
0
Initialization
SIO2CON
UARTCON
BRG
P7
P7D
1001X0012
XX001X002
6 – 1
...
..
TB/RB (address 001F16)
The first byte of a
transmission data
P7 (address 000E16), bit6
0
1
0
Port P76 set for communication control
An interval of 10 ms generated by Timer
Communication start
Transmission data write
Transmit buffer empty flag is set to “0”
by this writing.
Transmission data write
Transmit buffer empty flag is set to “0”
by this writing.
Judgment of transferring data from Transmit
buffer register to Transmit shift register
(Transmit buffer empty flag)
Judgment of transferring data from Transmit
buffer register to Transmit shift register
(Transmit buffer empty flag)
Judgment of shift completion of Transmit shift register
(Transmit shift register shift completion flag)
SIO2STS (address 001E16), bit0?
0
1
q X: This bit is not used here. Set it to “0” or “1” arbitrarily.
Serial I/O2 setting
...
..