180
3. APPE NDIX
MITSUBISHI MICROCOMPUTER
3819 Group
3.3 Control registers
3819 Group USER’S MANUAL
Fig. 3.3.3 Structure of Serial I/O automatic transfer data pointer
Fig. 3.3.4 Structure of Serial I/O 1 control register
When an external clock is selected in the serial I/O 1 automatic transfer
mode, the S
RDY1
signal pin is used as the CS signal input pin.
Serial I/O automatic transfer data pointer
b7 b6 b5 b4 b3 b2 b1 b0
B
0
Function
At reset
R W
1
2
3
4
6
7
0
0
Serial I/O automatic transfer data pointer (SIODP) [Address:18
16
]
Nothing is allocated for these bits. These are write disabled bits.
When these bits are read out, the values are "0."
Indicate an address of Serial I/O automatic transfer RAM.
0
5
Serial I/O 1 control register
b7 b6 b5 b4 b3 b2 b1 b0
B
0
Function
At reset
R W
0
1
2
3
4
5
6
7
0
0
0
0
0
0
0
Serial I/O 1 control register (SIO1CON) [Address:19
16
]
Name
Internal synchronous clock
selection bits
Synchronous clock selection
bit
P6
5
/S
OUT1
P-channel output
disable bit
000 : f(X
IN
)/8 or f(X
CIN
)/8
001 : f(X
IN
)/16 or f(X
CIN
)/16
010 : f(X
IN
)/32 or f(X
CIN
)/32
011 : f(X
IN
)/64 or f(X
CIN
)/64
110 : f(X
IN
)/128 or f(X
CIN
)/128
111 : f(X
IN
)/256 or f(X
CIN
)/256
0 : I/O port
1 : S
OUT1
, S
CLK11
, S
CLK12
signal pins
0 : External clock
1 : Internal clock
0 : CMOS output (in output mode)
1 : N-channel open-drain output
(in output mode)
b2 b1b0
Serial I/O 1 port selection bit
(P6
5
,P6
6
,P6
7
)
6
S
RDY1
output selection bit
(P6
7
)
Transfer direction selection
bit
0 : LSB first
1 : MSB first
0 : I/O port
1 : S
RDY1
/CS signal pin (
Note
)
6
6
Valid only in the Serial I/O automatic transfer mode
Note :