CHAPTER 12 A/D CONVERTER
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User’s Manual U11302EJ4V0UM
(2) A/D conversion by software start
When bit 6 (TRG) and bit 7 (CS) of the A/D converter mode register (ADM) are set to 0 and 1, respectively,
A/D conversion starts on the voltage applied to the analog input pins specified by bits 1 to 3 (ADM1 to
ADM3) of ADM.
At the end of A/D conversion, the conversion result is stored in the A/D conversion result register (ADCR)
and the interrupt request signal (INTAD) is generated. After one A/D conversion operation is started and
terminated, the next A/D conversion operation starts immediately. A/D conversion continues repeatedly
until new data is written to ADM.
If data with CS set to 1 is written to ADM again during A/D conversion, the converter suspends its A/D
conversion operation and starts A/D conversion on the newly written data.
If data with CS set to 0 is written to ADM during A/D conversion, the A/D conversion operation stops
immediately.
Figure 12-7. A/D Conversion by Software Start
Remark
n
= 0, 1, ... , 7
m = 0, 1, ... , 7
ANIn
INTAD
ADCR
A/D conversion
ANIn
ANIn
ANIm
ANIm
ANIn
ANIm
Conversion start
CS = 1, TRG = 0
ADM rewrite
CS = 1, TRG = 0
ADM rewrite
CS = 0, TRG = 0
Stop
ANIn
Conversion suspended
Conversion results
are not stored