A-D Converter
Mitsubishi microcomputers
M16C / 6N0 / 6N1 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
163
Figure 1.17.6. A-D conversion register in single sweep mode
Item
Specification
Function
The pins selected by the A-D sweep pin select bit are used for one-by-one A-D conversion.
Start condition
Writing "1" to A-D converter 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
AN0 and AN1 (2 pins), AN0 to AN3 (4 pins), AN0 to AN5 (6 pins), or AN0 to AN7 (8 pins)
Reading of result of A-D
converter
Read A-D register corresponding to selected pin
A-D control register 0 (Note)
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
CKS0
W
R
0
1
A-D control register 1 (Note 1)
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 (Note 2)
When single sweep and repeat sweep mode
0 are selected:
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
0 : Set to "0" when this mode is selected
1 : VREF connected
External op-amp
connection mode bit
(Note 4)
0 0 : ANEX0 and ANEX1 are not used
1 0 : AN0 to AN5 (6 pins)
1 1 : AN0 to AN7 (8 pins)
0 1 : AN0 to AN3 (4 pins)
0 0 : AN0, AN1 (2 pins)
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 single sweep mode
0
1 0 : Single sweep mode
b4 b3
CH0
b7 b6
b1 b0
1
Frequency select bit1
(Note 3)
0 : fAD2/2 or fAD2/4 is selected
CKS1
1 : fAD2 is selected
0 : f2AD/4 is selected
1 : f2AD/2 is selected
Note: If the A-D control register is rewritten during A-D conversion, the conversion
result is indeterminate.
Note 1: If the A-D control register is rewritten during A-D conversion, the conversion
result is indeterminate.
Note 2: AN00 to AN07 and AN20 to AN27 can be used in the same way as AN0 to AN7.
Note 3: Divide the frequency if f(XIN) exceeds 10MHz, and make AD frequency
equal to or less than 10MHz.
Note 4: Neither "01" nor "10" can be selected with the external op-amp connection
mode bit.
(3) Single sweep mode
In single sweep mode, the pins selected using the A-D sweep pin select bit are used for one-by-one A-D
conversion. Table 1.17.4 shows the specifications of single sweep mode. Figure 1.17.6 shows the A-D
control register in single sweep mode.
Table 1.17.4. Single sweep mode specifications