M30218 Datasheet, PDF (122/179 Pages) Mitsubishi Electric Semiconductor – M30218 Group

A-D converter
Mitsubishi microcomputers
M30218 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(4) Repeat sweep mode 0
In repeat sweep mode 0, the pins selected using the A-D sweep pin select bit are used for repeat sweep
A-D conversion. Table JA-5 shows the specifications of repeat sweep mode 0. Figure JA-7 shows the A-
D control register in repeat sweep mode 0.
Table JA-5. Repeat sweep mode 0 specifications
Item
Specification
Function
The pins selected by the A-D sweep pin select bit are used for repeat sweep A-D conversion
Start 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
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 (at any time)
A-D control register 0 (Note)
b7 b6 b5 b4 b3 b2 b1 b0
011
Symbol
ADCON0
Address
03D616
When reset
00000XXX2
Bit symbol
Bit name
Function
CH0
Analog input pin select bit Invalid in repeat sweep mode 0
RW
CH1
CH2
MD0
MD1
A-D operation mode
select bit 0
Must always be “0”.
b4 b3
1 1 : Repeat sweep mode 0
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 conversion result
is indeterminate.
A-D control register 1 (Note)
b7 b6 b5 b4 b3 b2 b1 b0
001
0
Symbol
ADCON1
Address
03D716
When reset
0016
Bit symbol
SCAN0
SCAN1
MD2
BITS
CKS1
VCUT
Bit name
A-D sweep pin select bit
A-D operation mode
select bit 1
8/10-bit mode select bit
Frequency select bit 1
Vref connect bit
Function
When repeat sweep mode 1 is selected
b1 b0
0 0 : AN0, AN1 (2 pins)
0 1 : AN0 to AN3 (4 pins)
1 0 : AN0 to AN5 (6 pins)
1 1 : AN0 to AN7 (8 pins)
1 : 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”.
RW
Note: If the A-D control register is rewritten during A-D conversion, the conversion result
is indeterminate.
Figure JA-7. A-D conversion register in repeat sweep mode 0
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