Unde
A-D Converter
deeopmen
Mitsubishi microcomputers
M30201 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
93
(1) One-shot mode
In one-shot mode, the pin selected using the analog input pin select bit is used for one-shot A-D conver-
sion. (See Table 1.31.) Figure 1.85 shows the A-D control register in one-shot mode.
Table 1.31. One-shot mode specifications
Figure 1.85. A-D conversion register in one-shot mode
Item
Specification
Function
Start condition
Stop condition
The pin selected by the analog input pin select bit is used for one A-D conversion
Writing “1” to A-D conversion start flag
End of A-D conversion (A-D conversion start flag changes to “0”)
Writing “0” to A-D conversion start flag
End of A-D conversion
One of AN
0
to AN
7
, as selected (Note)
Read A-D register corresponding to selected pin
Note : AN
50
to AN
54
can be used in the same way as for AN
0
to AN
4
.
Interrupt request generation timing
Input pin
Reading of result of A-D converter
A-D control register 0 (Note 1)
b7
b6
b5
b4
b3 b2
0
0 0
Symbol
ADCON0
Address
03D6
16
When reset
00000XXX
2
b1
b0
Analog input pin select bit
0
is selected
0 0 1 : AN
1
is selected
0 1 0 : AN
2
is selected
0 1 1 : AN
3
is selected
1 0 0 : AN
4
is selected
1 0 1 : AN
5
is selected
1 1 0 : AN
6
is selected
1 1 1 : AN
7
is selected
(Note 2)
CH0
Bit symbol
Bit name
Function
CH1
CH2
A-D operation mode
select bit 0
MD0
MD1
ADST
A-D conversion start flag
0 : A-D conversion disabled
1 : A-D conversion started
Frequency select bit 0
0 : f
AD
/4 is selected
1 : f
AD
/2 is selected
CKS0
W
R
A-D control register 1 (Note)
b7
b6
b5
b4
b3 b2
0
0
1
Symbol
ADCON1
Address
03D7
16
When reset
00
16
Bit name
Function
Bit symbol
b1
b0
A-D sweep pin select bit
SCAN0
SCAN1
MD2
BITS
8/10-bit mode select bit
0 : 8-bit mode
1 : 10-bit mode
VCUT
Vref connect bit
ADGSEL0
A-D operation mode
select bit 1
1 : Vref connected
A-D input group select bit
W
R
b2 b1 b0
b4 b3
0 : Port P6 group is selected
1 : Port P5 group is selected
Note 1: If the A-D control register is rewritten during A-D conversion, the conversion result is indeterminate.
Note 2: AN
50
to AN
54
can be used in the same way as for AN
0
to AN
4
.
Frequency select bit 1
0 : f
AD
/2 or f
AD
/4 is selected
1 : f
AD
is selected
CKS1
Note: If the A-D control register is rewritten during A-D conversion, the conversion result is indeterminate.
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
Set this bit to “0”.
Set this bit to “0”.
Invalid in one-shot mode
Set this bit to “0” in this mode.