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CHAPTER 12 10-BIT A/D CONVERTER (
µ
PD780034AS SUBSERIES)
Preliminary User’s Manual U16035EJ1V0UM
(2) A/D conversion by software start
When bit 6 (TRG0) and bit 7 (ADCS0) of the A/D converter mode register 0 (ADM0) are set to 0 and 1, respectively,
A/D conversion of the voltage applied to the analog input pin specified by the analog input channel specification
register 0 (ADS0) starts.
Upon the end of the A/D conversion, the conversion result is stored in the A/D conversion result register 0
(ADCR0), and the interrupt request signal (INTAD0) is generated. After one A/D conversion operation is started
and ended, the next conversion operation is immediately started. A/D conversion operations are repeated until
new data is written to ADS0.
If ADS0 is rewritten during A/D conversion, the converter suspends A/D conversion and A/D conversion of the
new selected analog input channel is started.
If data with ADCS0 set to 0 is written to ADM0 during A/D conversion, the A/D conversion operation stops
immediately.
Figure 12-8. A/D Conversion by Software Start
ADM0 set
ADCS0 = 1, TRG0 = 0
ADS0 rewrite
ADCS0 = 0
A/D conversion
ADCR0
INTAD0
ANIn
ANIn
ANIn
ANIm
ANIm
Stop
ANIn
ANIn
ANIm
Conversion suspended;
Conversion results are not stored
Remarks 1.
n = 0, 1, ......, 7
2.
m = 0, 1, ......, 7