
120
A-D converter
Mitsubishi microcomputers
M30218 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(2) Repeat mode
In repeat mode, the pin selected using the analog input pin select bit is used for repeated A-D conversion. Table
32 shows the specifications of repeat mode. Figure 105 shows the A-D control register in repeat mode.
Table 32. Repeat mode specifications
Item
Specification
Function
The pin selected by the analog input pin select bit is used for repeated A-D conversion
Star condition
Writing “1” to A-D conversion start flag
Stop condition
Writing “0” to A-D conversion start flag
Interrupt request generation timing None generated
Input pin
One of AN0 to AN7, as selected
Reading of result of A-D converter Read A-D register corresponding to selected pin
Figure 105. A-D conversion register in repeat mode
A-D control register 0 (Note)
Symbol
Address
When reset
ADCON0
03D616
00000XXX2
Bit name
Function
Bit symbol
b7
b6
b5
b4
b3
b2
b1
b0
Analog input pin
select bit
CH0
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 : fAD/4 is selected
1 : fAD/2 is selected
CKS0
W
R
01
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
1 1 1 : AN7 is selected
b2 b1 b0
0 1 : Repeat mode
b4 b3
Note: If the A-D control register is rewritten during A-D conversion, the conversin
result is indeterminate.
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
Vref connect bit
A-D operation mode
select bit 1
1 : Vref connected
W
R
Invalid in repeat mode
0
1
Frequency select bit 1
0 : fAD/2 or fAD/4 is selected
1 : fAD is selected
CKS1
0 : Any mode other than repeat sweep mode 1
Note: If the A-D control register is rewritten during A-D conversion, the conversn
result is indeterminate.
0
Must always be “0”.