M30218 Datasheet, PDF (123/179 Pages) Mitsubishi Electric Semiconductor – M30218 Group

A-D converter
Mitsubishi microcomputers
M30218 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(5) Repeat sweep mode 1
In repeat sweep mode 1, all pins are used for A-D conversion with emphasis on the pin or pins selected
using the A-D sweep pin select bit. Table JA-6 shows the specifications of repeat sweep mode 1. Figure
JA-8 shows the A-D control register in repeat sweep mode 1.
Table JA-6. Repeat sweep mode 1 specifications
Item
Function
Specification
All pins perform repeat sweep A-D conversion, with emphasis on the pin or
pins selected by the A-D sweep pin select bit
Example : AN0 selected -> AN0 -> AN1 -> AN0 -> AN2 -> AN0 -> AN3, etc
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
Emphasis on the pin AN0 (1 pin), AN0 and AN1 (2 pins), AN0 to AN2 (3 pins), AN0 to AN3 (4 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 1
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
1
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 (1 pins)
0 1 : AN0, AN1 (2 pins)
1 0 : AN0 to AN2 (3 pins)
1 1 : AN0 to AN3 (4 pins)
1 : 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-8. A-D conversion register in repeat sweep mode 1
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