Datasheet

Rev. 3.00, 03/04, page 593 of 830
17.4 Operation
The D/A converter incorporates two channels of the D/A circuits and can be converted
individually.
When the DAOE bit in DACR is set to 1, D/A conversion is enabled and conversion results are
output.
An example of D/A conversion of channel 0 is shown below. The operation timing is shown in
figure 17.2.
1. Write conversion data to DADR0.
2. When the DAOE0 bit in DACR is set to 1, D/A conversion starts. After the interval of t
DCONV
,
conversion results are output from the analog output pin DA0. The conversion results are
output continuously until DADR0 is modified or the DAOE0 bit is cleared to 0. The output
value is calculated by the following formula:
DADR contents/256
x AVref
3. Conversion starts immediately after DADR0 is modified. After the interval of t
DCONV
,
conversion results are output.
4. When the DAOE bit is cleared to 0, analog output is disabled.
DADR0
write cycle
DACR
write cycle
DADR0
write cycle
DACR
write cycle
Address
φ
DADR0
DAOE0
DA
0
Conversion data (1) Conversion data (2)
High impedance state
Conversion result (1)
Conversion
result (2)
t
DCONV
t
DCONV
[Legend]
t
DCONV
: D/A conversion time
Figure 17.2 D/A Converter Operation Example