
2-26
3802 GROUP USER’S MANUAL
APPLICATION
2.3 Serial I/O
A count value of Baud rate generator is set.
Function
Baud rate generator (BRG) [Address : 1C
16
]
B
0
Baud rate generator
b7 b6 b5 b4 b3 b2 b1 b0
At reset
R W
1
2
3
4
5
6
7
Fig. 2.3.6 Structure of Baud rate generator
Fig. 2.3.7 Structure of Serial I/O2 control register
Serial I/O2 control register (SIO2CON) [Address : 1D
16
]
B
0
Internal synchronous clock
selection bits
Serial I/O2 control register
b7 b6 b5 b4 b3 b2 b1 b0
Function
At reset
R W
0
1
2
3
0
0
0
Name
4
5
6
7
0
0
0
S
RDY2
output enable bit
0 : I/O port (P5
1
, P5
2
)
1 : S
OUT2
, S
CLK2
output pin
0 : I/O port (P5
3
)
1 :
S
RDY2
output pin
0 : LSB first
1 : MSB first
0 : External clock
1 : Internal clock
In output mode
0 0 0 : f(X
IN
)/8
0 0 1 : f(X
IN
)/16
0 1 0 : f(X
IN
)/32
0 1 1 : f(X
IN
)/64
1 1 0 : f(X
IN
)/128
1 1 1 : f(X
IN
)/256
Transfer direction selection bit
Serial I/O2 port selection bit
Serial I/O2 synchronous clock
selection bit
P5
1
/S
OUT2
P-channel
output disable bit
b2 b1 b0
0 : CMOS output
1 : N-channel open-drain output
0