upd70f3017ay Renesas Electronics Corporation., upd70f3017ay Datasheet - Page 320

• Manufacturer Part Number: upd70f3017ay
• Description: V850/sa1tm 32-/16-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

(1) A/D conversion by hardware start
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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 A/D conversion has been completed, the result of the conversion is stored in the A/D conversion result
register (ADCR), and an interrupt request signal (INTAD) is generated. Once in 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 A/D 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.
Caution Be sure to make the input interval of the external trigger signal higher than the conversion time
A/D conversion
External trigger
input signal
Remarks 1.
INTAD
ADCR
specified by the FR2 to FR0 bits of the ADM register + 6 CPU clocks.
2.
Figure 11-4. A/D Conversion by Hardware Start (with Falling Edge Specified)
Rewriting ADS
ADCS = 1, TRG = 1
n = 0, 1, ..., 11
m = 0, 1, ..., 11
Standby
status
CHAPTER 11 A/D CONVERTER
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User’s Manual U12768EJ4V1UD
ANIn
ANIn
Standby
status
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Rewriting ADS
ADCS = 1, TRG = 1
Standby
status
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ANIm
ANIm
ANIm
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