M30218 Datasheet, PDF (119/179 Pages) Mitsubishi Electric Semiconductor – M30218 Group

A-D converter
Mitsubishi microcomputers
M30218 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 conversion. Table
JA-2 shows the specifications of one-shot mode. Figure JA-4 shows the A-D control register in one-shot mode.
Table JA-2. One-shot mode specifications
Item
Specification
Function
Start 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
Stop condition
•End of A-D conversion (A-D conversion start flag changes to “0”)
•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
000
Symbol
ADCON0
Address
03D616
When reset
00000XXX2
Bit symbol
Bit name
CH0
Analog input pin
select bit
CH1
CH2
MD0
MD1
A-D operation mode
select bit 0
Must always be “0”.
Function
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
b4 b3
0 0 : One-shot mode
RW
ADST
CKS0
A-D conversion start flag
Frequency select bit 0
0 : A-D conversion disabled
1 : A-D conversion started
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
0 01
0
Symbol
ADCON1
Address
03D716
When reset
0016
Bit symbol
Bit name
SCAN0
SCAN1
A-D sweep pin
select bit
Function
Invalid in one-shot mode
MD2
BITS
CKS1
VCUT
A-D operation mode
select bit 1
8/10-bit mode select bit
Frequency select bit1
0 : Any mode other than repeat sweep
mode 1
0 : 8-bit mode
1 : 10-bit mode
0 : fAD/2 or fAD/4 is selected
1 : fAD is selected
Vref connect bit
1 : Vref connected
Must always be “0”.
RW
Note: If the A-D control register is rewritten during A-D conversion, the conversion
result is indeterminate.
Figure JA-4. A-D conversion register in one-shot mode
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