106
Serial I/O2
M
i
t
s
u
M
S
b
i
s
3
M
h
0
I
C
i
m
2
R
i
1
O
c
r
8
C
o
c
o
G
M
m
p
r
P
u
t
u
T
e
r
p
R
s
o
U
S
I
N
G
L
E
-
C
H
I
P
1
6
-
B
I
T
C
M
O
O
E
Table 29. Functions of the serial I/O2 input/output pins
Table 29 lists the functions of the serial I/O2 input/output pins
Pin name
Function
Method of selection
S
OUT2
(P9
4
)
Serial data output
Serial data input
Transfer clock output
Transfer clock input
Port P9
4
direction register (bit 4 at address 03F3
16
)= “1”
S
OUT2
P-channel output disable bit (bit 7 at address 0344
16
)= “0” , “1”
S
OUT2
pin control bit (bit 6 at address 0344
16
)= “0” , “1”
(Outputs dummy data when performing reception only)
Port P9
3
direction register (bit 4 at address 03F3
16
)= “0”
Transfer mode select bit (bit 5 at address 0342
16
)= “0”
(Input/output port when transfer mode select bit (bit 5 at address 0342
16
)= “1”)
S
IN2
(P9
3
)
S
CLK21
(P9
5
)
Serial I/O2 synchronous clock select bits (bits 2, 3 at address 0342
16
) = “00” , “01”
Serial I/O2 clock pin select bit (bit 7 at address 0342
16
) = “0”
Serial I/O2 synchronous clock select bits (bits 2, 3 at address 0342
16
) = “01” , “11”
Serial I/O2 clock pin select bit (bit 7 at address 0342
16
) = “0”
Port P9
5
direction register (bit 5 at address 03F3
16
)= “0”
Transfer clock output
Transfer clock input
S
CLK22
(P9
6
)
Serial I/O2 synchronous clock select bits (bits 2, 3 at address 0342
16
) = “00” , “01”
Serial I/O2 clock pin select bit (bit 7 at address 0342
16
) = “1”
Serial I/O2 synchronous clock select bits (bits 2, 3 at address 0342
16
) = “01” , “11”
Serial I/O2 clock pin select bit (bit 7 at address 0342
16
) = “1”
Port P9
6
direction register (bit 6 at address 03F3
16
)= “0”
Set by S
RDY2
S
BUSY2
pin control bits (bits 0 to 3 at address 0344
16
)
S
RDY
input / output
S
RDY2
(P9
0
)
S
BUSY
input / output
S
BUSY2
(P9
1
)
Set by S
RDY2
S
BUSY2
pin control bits (bits 0 to 3 at address 0344
16
)
S
BUSY2
output S
STB2
output function select bit (bit 4 at address 0344
16
)= “0” , “1”
S
STB
input / output
S
STB2
(P9
2
)
Serial I/O2 synchronous clock select bits (bits 2, 3 at address 0342
16
) = “10” , “11”
S
BUSY2
output S
STB2
output function select bit (bit 4 at address 0344
16
)= “0” , “1”
S
OUT2
Output
Either output active or high-impedance can be selected as a S
OUT2
pin state at serial non-transfer by the
S
OUT2
pin control bit (bit 6 of address 0344
16
).
However, when the external synchronous clock is selected, perform the following setup to put the S
OUT2
pin into a high-impedance state.
When the S
CLK2i ( i = 1, 2)
input is “H” after completion of transfer, set the S
OUT2
pin control bit to “1”. When
the S
CLK2i ( i = 1, 2)
input goes to “L” after the start of the next serial transfer, the S
OUT2
pin control bit is
automatically reset to “0” and put into an output active state.