Renesas RL78 Series User Manual page 361

RL78/G1D
12.6 A/D Converter Operation Modes
The operation of each A/D converter mode is described below. In addition, the procedure for specifying each mode is
described in 12.7 A/D Converter Setup Flowchart.
12.6.1 Software trigger mode (select mode, sequential conversion mode)
<1> In the stop status, the ADCE bit of A/D converter mode register 0 (ADM0) is set to 1, and the system enters the
A/D conversion standby status.
<2> After the software counts up to the stabilization wait time (1 µs), the ADCS bit of the ADM0 register is set to 1 to
perform the A/D conversion of the analog input specified by the analog input channel specification register (ADS).
<3> When A/D conversion ends, the conversion result is stored in the A/D conversion result register (ADCR, ADCRH),
and the A/D conversion end interrupt request signal (INTAD) is generated. After A/D conversion ends, the next
A/D conversion immediately starts.
<4> When ADCS is overwritten with 1 during conversion operation, the current A/D conversion is interrupted, and
conversion restarts. The partially converted data is discarded.
<5> When the value of the ADS register is rewritten or overwritten during conversion operation, the current A/D
conversion is interrupted, and A/D conversion is performed on the analog input respecified by the ADS register.
The partially converted data is discarded.
<6> Even if a hardware trigger is input during conversion operation, A/D conversion does not start.
<7> When ADCS is cleared to 0 during conversion operation, the current A/D conversion is interrupted, and the
system enters the A/D conversion standby status.
<8> When ADCE is cleared to 0 while in the A/D conversion standby status, the A/D converter enters the stop status.
When ADCE = 0, specifying 1 for ADCS is ignored and A/D conversion does not start.
Figure 12-17. Example of Software Trigger Mode (Select mode, Sequential Conversion Mode) Operation Timing
ADCE is set to 1.
<1>
ADCE
ADCS is set to 1 while in the
<2>
The trigger
conversion standby status.
is not
acknowledged.
ADCS
ADS
A/D
Stop
Conversion Data 0
conversion
status
standby (ANI0)
status
ADCR,
ADCRH
INTAD
R01UH0515EJ0120 Rev.1.20
Dec 16, 2016
ADCS is overwritten
<4>
with 1 during A/D
conversion operation.
Data 0
(ANI0)
Conversion is
A/D conversion
<3>
<3>
interrupted
ends and the next
conversion starts.
and restarts.
Data 0 Data 0 Data 0
(ANI0) (ANI0) (ANI0)
Data 0 Data 0
(ANI0) (ANI0)
CHAPTER 12 A/D CONVERTER
A hardware trigger
<6>
is generated
(and ignored).
ADS is rewritten during
<5>
A/D conversion operation
(from ANI0 to ANI1).
Data 1
(ANI1)
<3> <3>
Data 1 Data 1
Data 0
(ANI1) (ANI1)
(ANI0)
Data 1
Data 0
(ANI1)
(ANI0)
ADCE is cleared to 0. <8>
ADCS is cleared to
<7>
0 during A/D
conversion operation.
Conversion is
<3>
interrupted.
Conversion
Data 1
(ANI1) standby
Data 1
(ANI1)
The trigger
is not
acknowledged.
Stop
status
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