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CHAPTER 13 A/D CONVERTER
User’s Manual U12697EJ3V0UM
Figure 13-4. Basic Operations of A/D Converter
A/D conversion is performed continuously until bit 7 (ADCS) of A/D converter mode register (ADM) is reset 0 by
software.
If a write operation to ADM or the A/D converter input selection register (ADIS) is performed during A/D conversion,
the conversion operation is initialized and conversion starts from the beginning if the ADCS bit is set 1.
RESET input makes A/D conversion result register (ADCR) undefined.
If bit 0 (ADCE) of the A/D converter mode register is not set to 1, the value of the first A/D conversion is undefined
immediately after A/D conversion starts. Poll the A/D conversion end interrupt request (INTAD) and take measures
such as discarding the first A/D conversion result.
SAR
ADCR
INTAD
A/D converter
operation
Sampling time
Sampling
A /D conversion
Conversion
time
Undefined
80H
C0H
or
40H
Conversion
result
Conversion
result