A/D Conversion By Hardware Start (With Falling Edge Specified) - NEC V850/SA1 mPD703015 Preliminary User's Manual

(1) A/D conversion by hardware start
A/D conversion is on standby if bit 6 (TRG) and bit 7 (ADCS) of the A/D converter mode register (ADM) are set to
1. When an external trigger signal is input, the A/D converter starts converting the voltage applied to the analog
input pin specified by the analog input channel specification register (ADS) into a digital signal.
When the A/D conversion has been completed, the result of the conversion is stored to the A/D conversion result
register (ADCR), and an interrupt request signal (INTAD) is generated. Once the A/D conversion has been
started and completed, conversion is not started again unless a new external trigger signal is input.
If data with ADCS set to 1 is written to ADM during conversion, the conversion under execution is stopped, and
the A/D converter stands by until a new external trigger signal is input. If the external trigger signal is input, A/D
conversion is executed again from the beginning.
If data with ADCS set to 0 is written to ADM during A/D conversion, the conversion is immediately stopped.
Figure 11-6. A/D Conversion by Hardware Start (with falling edge specified)
External trigger
input signal
Rewriting ADS
ADCS = 1, TRG = 1
A/D conversion
ADCR
INTAD
Remarks 1. n = 0, 1, ..., 11
2. m = 0, 1, ..., 11
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CHAPTER 11
Standby
ANIn ANIn
status
ANIn
A/D CONVERTER
Rewriting ADS
ADCS = 1, TRG = 1
Standby Standby
ANIn
status status
ANIn ANIn
ANIm ANIm ANIm
ANIm ANIm