h8s-2169 Renesas Electronics Corporation., h8s-2169 Datasheet - Page 687

• Manufacturer Part Number: h8s-2169
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

19.3
The D/A converter module has two built-in D/A converter circuits that can operate independently.
D/A conversion is performed continuously whenever enabled by the D/A control register (DACR).
When a new value is written in DADR0 or DADR1, conversion of the new value begins
immediately. The converted result is output by setting the DAOE0 or DAOE1 bit to 1.
An example of conversion on channel 0 is given next. Figure 19.2 shows the timing.
Address
DADR0
DAOE0
DA0
t
DCONV
Software writes the data to be converted in DADR0.
D/A conversion begins when the DAOE0 bit in DACR is set to 1. After the elapse of the
conversion time, analog output appears at the DA0 pin. The output value is AVref
value)/256.
This output continues until a new value is written in DADR0 or the DAOE0 bit is cleared to 0.
If a new value is written in DADR0, conversion begins immediately. Output of the converted
result begins after the conversion time.
When the DAOE0 bit is cleared to 0, DA0 becomes an input pin.
: D/A conversion time
Operation
DADR0
write cycle
High-impedance state
DACR
write cycle
Figure 19.2 D/A Conversion (Example)
Conversion data (1)
t
DCONV
Conversion result (1)
Rev. 3.00 Jan 18, 2006 page 659 of 1044
DADR0
write cycle
t
DCONV
Section 19 D/A Converter
Conversion data (2)
Conversion result (2)
REJ09B0280-0300
DACR
write cycle
(DADR