M30218 Datasheet, PDF (120/179 Pages) Mitsubishi Electric Semiconductor – M30218 Group

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
JA-3 shows the specifications of repeat mode. Figure JA-5 shows the A-D control register in repeat mode.
Table JA-3. 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
A-D control register 0 (Note)
b7 b6 b5 b4 b3 b2 b1 b0
001
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 1 : Repeat mode
RW
ADST
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 conversin
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
Function
SCAN0 A-D sweep pin select bit Invalid in repeat mode
RW
SCAN1
MD2
BITS
CKS1
VCUT
A-D operation mode
select bit 1
8/10-bit mode select bit
Frequency select bit 1
Vref connect bit
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
1 : Vref connected
Must always be “0”.
Note: If the A-D control register is rewritten during A-D conversion, the conversn
result is indeterminate.
Figure JA-5. A-D conversion register in repeat mode
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