M16C30_02 Datasheet, PDF (135/178 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

A-D Converter
Mitsubishi microcomputers
M16C / 30 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 1.17.2 shows the specifications of one-shot mode. Figure 1.17.4 shows the A-D control regis-
ter in one-shot mode.
Table 1.17.2. One-shot mode specifications
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
Reading of result of A-D converter Read A-D register corresponding to selected pin
A-D control register 0 (Note)
b7 b6 b5 b4 b3 b2 b1 b0
00
Symbol
ADCON0
Address When reset
03D616 00000XXX2
Bit symbol
Bit name
Function
RW
CH0
CH1
CH2
Analog input pin select
bit
b2 b1 b0
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
MD0
MD1
TRG
ADST
A-D operation mode
select bit 0
b4 b3
0 0 : One-shot mode
Trigger select bit
0 : Software trigger
1 : ADTRG trigger
A-D conversion start flag 0 : A-D conversion disabled
1 : A-D conversion started
CKS0
Frequency select bit 0
0: fAD/4 is selected
1: fAD/2 is selected
Note : If the A-D control register is rewritten during A-D conversion, the conversion
result is indeterminate.
A-D control register 1 (Note)
b7 b6 b5 b4 b3 b2 b1 b0
1
000
Symbol
ADCON1
Address
03D716
When reset
0016
Bit symbol
Bit name
Function
RW
Reserved bit
Must always be set to “0”
BITS
CKS1
8/10-bit mode select bit
Frequency select bit1
0 : 8-bit mode
1 : 10-bit mode
0 : fAD/2 or fAD/4 is selected
1 : fAD is selected
VCUT Vref connect bit
1 : Vref connected
OPA0
OPA1
External op-amp
connection mode bit
b7 b6
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
Note: If the A-D control register is rewritten during A-D conversion, the conversion
result is indeterminate.
Figure 1.17.4. A-D conversion register in one-shot mode
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