
214
CHAPTER 12 A/D CONVERTER
User
’
s Manual U14701EJ3V0UD
Figure 12-2. A/D Converter Mode Register 0 (ADM0) Format
Address: FF80H After reset: 00H R/W
Symbol
7
6
5
4
3
2
1
0
ADM0
ADCS0
TRG0
FR02
FR01
FR00
EGA01
EGA00
ADCE0
ADCS0
A/D conversion operation control
0
Stop conversion operation.
1
Enable conversion operation.
TRG0
Software start/hardware start selection
0
Software start
1
Hardware start
FR02
FR01
FR00
Conversion time selection
Note 1
0
0
0
144/f
X
(14.4
μ
s)
0
0
1
120/f
X
(Setting prohibited
Note 2
)
0
1
0
96/f
X
(Setting prohibited
Note 2
)
1
0
0
576/f
X
(57.6
μ
s)
1
0
1
480/f
X
(48.0
μ
s)
1
1
0
384/f
X
(38.4
μ
s)
Other than above
Setting prohibited
EGA01
EGA00
External trigger signal, edge specification
0
0
No edge detection
0
1
Falling edge detection
1
0
Rising edge detection
1
1
Both falling and rising edge detection
ADCE0
Control of voltage booster for A/D converter circuit
Note 3
0
Stops operation.
1
Enables operation.
Notes 1.
Set so that the A/D conversion time is 14
μ
s or more.
2.
Setting prohibited because A/D conversion time is less than 14
μ
s.
3.
Before executing A/D conversion (ADCS0 = 1), be sure to start the voltage booster (ADCE0 = 1).
Cautions 1. When rewriting FR00 to FR02 to other than the same data, stop A/D conversion operations
once before performing it.
2. Make sure by using software that a wait time of 14
μ
s (MIN.) elapses between when ADCE0
is set and when ADCS0 is set.
3. Before clearing ADCE0, clear ADCS0.
Remarks 1.
f
X
: Main system clock oscillation frequency
2.
Figures in parentheses are for operation with f
X
= 10 MHz.