A-D Converter
156
Mitsubishi microcomputers
M16C / 62N Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(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. Table 1.18.2 shows the specifications of one-shot mode. Figure 1.18.4 shows the A-D control regis-
ter in one-shot mode.
Table 1.18.2. One-shot mode specifications
Figure 1.18.4. A-D conversion register in one-shot mode
A-D control register 0 (Note 1)
Symbol
Address
When reset
ADCON0
03D616
00000XXX2
b7
b6
b5
b4
b3
b2
b1
b0
Analog input pin select
bit
Bit symbol
Bit name
Function
CH1
CH2
A-D operation mode
select bit 0
MD0
MD1
Trigger select bit
0 : Software trigger
1 : ADTRG trigger
TRG
ADST
A-D conversion start flag
0 : A-D conversion disabled
1 : A-D conversion started
Frequency select bit 0
0: fAD/4 is selected
1: fAD/2 is selected
CKS0
W
R
0
A-D control register 1 (Note)
Symbol
Address
When reset
ADCON1
03D716
0016
Bit name
Function
Bit symbol
b7
b6
b5
b4
b3
b2
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
OPA0
Vref connect bit
OPA1
A-D operation mode
select bit 1
Set to “0” when this mode is selected
1 : Vref connected
External op-amp
connection mode bit
0 0 : ANEX0 and ANEX1 are not used
0 1 : ANEX0 input is A-D converted
1 0 : ANEX1 input is A-D converted
1 1 : External op-amp connection mode
W
R
Invalid in one-shot mode
0
0 0 0 : AN0 is selected
0 0 1 : AN1 is selected
0 1 0 : AN2 is selected
0 1 1 : AN3 is selected
1 0 0 : AN4 is selected
1 0 1 : AN5 is selected
1 1 0 : AN6 is selected
(Note 2)
1 1 1 : AN7 is selected
(Note 3)
b2 b1 b0
0 0 : One-shot mode
(Note 3)
b4 b3
CH0
b7 b6
1
Note 1: If the A-D control register is rewritten during A-D conversion, the conversion
result is indeterminate.
Note 2: AN00 to AN07 can be used the same as AN0 to AN7.
Note 3: When changing A-D operation mode, set analog input pin again.
Frequency select bit1
0 : fAD/2 or fAD/4 is selected
1 : fAD is selected
CKS1
Note: If the A-D control register is rewritten during A-D conversion, the conversion
result is indeterminate.
Item
Specification
Function
The pin selected by the analog input pin select bit is used for one A-D conversion
Start condition
Writing “1” to A-D conversion start flag
Stop condition
End of A-D conversion (A-D conversion start flag changes to “0”, except
when external trigger is selected)
Writing “0” to A-D conversion start flag
Interrupt request generation timing
End of A-D conversion
Input pin
One of AN0 to AN7, as selected (Note)
Reading of result of A-D converter
Read A-D register corresponding to selected pin
Note : AN00 to AN07 can be used the same as AN0 to AN7.