
A-D Converter
M30240 Group
Rev.1.00 Sep 24, 2003 Page 232 of 360
Figure 2.77: A-D converter related registers (2)
Figure 2.78: A-D converter related registers (3)
A-D control register 1 (Note)
Symbol
Address
When reset
ADCON1
03D716
0016
Bit name
Function
Bit symbol
b7
b6
b5
b4
b3
b2
b1
b0
A-D sweep pin select bit
SCAN0
SCAN1
MD2
BITS
8/10-bit mode select bit
0 : 8-bit mode
1 : 10-bit mode
VCUT
Vref connect bit
A-D operation mode
select bit 1
0 : Any mode other than repeat sweep
mode 1
1 : Repeat sweep mode 1
0 : Vref not connected
1 : Vref connected
Reserved bit
W
R
When single sweep and repeat sweep
mode 0 are selected
0 0 : AN 0, AN1 (2 pins)
0 1 : AN 0 to AN3 (4 pins)
1 0 : AN 0 to AN5 (6 pins)
1 1 : AN 0 to AN7 (8 pins)
b1 b0
When repeat sweep mode 1 is selected
0 0 : AN 0 (1 pin)
0 1 : AN 0, AN1 (2 pins)
1 0 : AN 0 to AN2 (3 pins)
1 1 : AN 0 to AN3 (4 pins)
b1 b0
Always set to "0"
Frequency select bit 1
0 : fAD/2 or fAD/4 is selected
1 : fAD is selected
CKS1
Note: If the A-D control register is rewritten during A-D conversion, the conversion result is
indeterminate.
00
A-D control register 1 (Note)
Symbol
Address
When reset
ADCON1
03D716
0016
Bit name
Function
Bit symbol
b7
b6
b5
b4
b3
b2
b1
b0
A-D sweep pin select bit
SCAN0
SCAN1
MD2
BITS
8/10-bit mode select bit
0 : 8-bit mode
1 : 10-bit mode
VCUT
Vref connect bit
A-D operation mode
select bit 1
0 : Any mode other than repeat sweep
mode 1
1 : Repeat sweep mode 1
0 : Vref not connected
1 : Vref connected
Reserved bit
W
R
When single sweep and repeat sweep
mode 0 are selected
0 0 : AN 0, AN1 (2 pins)
0 1 : AN 0 to AN3 (4 pins)
1 0 : AN 0 to AN5 (6 pins)
1 1 : AN 0 to AN7 (8 pins)
b1 b0
When repeat sweep mode 1 is selected
0 0 : AN 0 (1 pin)
0 1 : AN 0, AN1 (2 pins)
1 0 : AN 0 to AN2 (3 pins)
1 1 : AN 0 to AN3 (4 pins)
b1 b0
Always set to "0"
Frequency select bit 1
0 : fAD/2 or fAD/4 is selected
1 : fAD is selected
CKS1
Note: If the A-D control register is rewritten during A-D conversion, the conversion result is
indeterminate.
00
A-D control register 2 (Note)
Symbol
Address
When reset
ADCON2
03D416
XXXX00002
b7
b6
b5
b4
b3
b2
b1
b0
A-D conversion method
select bit
0 : Without sample and hold
1 : With sample and hold
Bit symbol
Bit name
Function
R W
Note: If the A-D control register is rewritten during A-D conversion, the conversion
result is indeterminate.
Nothing is assigned.
In an attempt to write to these bits, write “0”. The value, if read, turns out to
be “0”.
A-D register i
Symbol
Address
When reset
ADi(i=0 to 7)
03C016 to 03CF16
Indeterminate
Eight low-order bits of A-D conversion result
Function
R W
(b15)
b7
b0
(b8)
During 10-bit mode
Two high-order bits of A-D conversion result
Nothing is assigned.
In an attempt to write to these bits, write “0”. The value, if
read, turns out to be “0”.
During 8-bit mode
When read, the content is indeterminate
SMP
Reserved bit
Always set to “0”
000