HD6433045 HITACHI [Hitachi Semiconductor], HD6433045 Datasheet - Page 560

• Manufacturer Part Number: HD6433045
• Description: Hitachi Single-Chip Microcomputer
• Manufacturer: HITACHI [Hitachi Semiconductor]

16.3 Operation
The D/A converter has two built-in D/A conversion circuits that can perform conversion
independently.
D/A conversion is performed constantly while enabled in DACR. If the DADR0 or DADR1 value
is modified, conversion of the new data begins immediately. The conversion results are output
when bits DAOE0 and DAOE1 are set to 1.
An example of D/A conversion on channel 0 is given next. Timing is indicated in figure 16-2.
1.
2.
3.
4.
Data to be converted is written in DADR0.
Bit DAOE0 is set to 1 in DACR. D/A conversion starts and DA
converted result is output after the conversion time. The output value is (DADR0
contents/256)
modified or the DAOE0 bit is cleared to 0.
If the DADR0 value is modified, conversion starts immediately, and the result is output after
the conversion time.
When the DAOE0 bit is cleared to 0, DA
ø
Address
bus
DADR0
DAOE0
DA
Legend
t
DCONV
0
: D/A conversion time
DADR0
write cycle
High-impedance state
V
Figure 16-2 Example of D/A Converter Operation
REF
. Output of this conversion result continues until the value in DADR0 is
DACR
write cycle
Conversion data 1
t
DCONV
0
becomes an input pin.
550
Conversion
result 1
DADR0
write cycle
0
t
DCONV
becomes an output pin. The
Conversion data 2
Conversion
result 2
DACR
write cycle