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RL78/G1A 
 
CHAPTER  11   A/D  CONVERTER 
R01UH0305EJ0200  Rev.2.00 
 
 
374  
Jul 04, 2013 
11.6.3  Software trigger mode (scan 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
Note
, the ADCS bit of the ADM0 register is set to 1 to 
perform A/D conversion on the four analog input channels specified by scan 0 to scan 3, which are specified by 
the analog input channel specification register (ADS).  A/D conversion is performed on the analog input channels 
in order, starting with that specified by scan 0. 
<3>  A/D conversion is sequentially performed on the four analog input channels, the conversion results are stored in 
the A/D conversion result register (ADCR, ADCRH) each time conversion ends, and the A/D conversion end 
interrupt request signal (INTAD) is generated.  After A/D conversion of the four channels ends, the A/D 
conversion of the channel following the specified channel automatically starts (until all four channels are finished). 
<4>  When ADCS is overwritten with 1 during conversion operation, the current A/D conversion is interrupted, and 
conversion restarts at the first channel.  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 first channel 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. 
 
Note  If a high-accuracy channel is selected as the analog input channel:  Stabilization wait time = 0.5 
μ
If a standard channel is selected as the analog input channel: 
Stabilization wait time = 2 
μ
 
Figure 11-19.  Example of Software Trigger Mode (Scan Mode, Sequential Conversion Mode) Operation Timing 
 
ADCE
ADCS
ADS
INTAD
ADCR,
ADCRH
A/D
conversion
status
ADCE is set to 1.
<1>
ADCE is cleared to 0. <8>
The trigger
is not
acknowledged.
The trigger
is not
acknowledged.
ADCS is set to 1 while in the 
conversion standby status.
<2>
Conversion
standby
Conversion
standby
Stop
status
Stop
status
Data 1
(ANI0)
Data 1
(ANI0)
Data 2
(ANI1)
Data 2
(ANI1)
Data 3
(ANI2)
Data 3
(ANI2)
Data 4
(ANI3)
Data 7
(ANI0)
Data 8
(ANI1)
Data 14
(ANI5)
Data 14
(ANI5)
Data 13
(ANI4)
Data 13
(ANI4)
Data 17
(ANI4)
Data 8
(ANI1)
Data 9
(ANI2)
Data 9
(ANI2)
Data 10
(ANI3)
Data 11
(ANI0)
Data 10
(ANI3)
Data 16
(ANI7)
Data 16
(ANI7)
Data 15
(ANI6)
Data 15
(ANI6)
Data 4
(ANI3)
Data 11
(ANI0)
Data 17
(ANI4)
Data 5
(ANI0)
Data 6
(ANI1)
Data 12
(ANI1)
Data 18
(ANI5)
Conversion is 
interrupted and restarts.
Conversion is 
interrupted and restarts.
Conversion is
interrupted.
A/D conversion ends and the 
next conversion starts.
<3>
ADCS is overwritten 
with 1 during A/D 
conversion operation.
<4>
<3>
<3>
ADS is rewritten during 
A/D conversion operation.
<5>
ADCS is cleared 
to 0 during A/D 
conversion operation.
<7>
A hardware trigger is 
generated (and ignored).
<6>
The interrupt is generated four times.
The interrupt is generated four times.
The interrupt is generated four times.
Data 5 
(ANI0)
ANI4 to ANI7
ANI0 to ANI3
Data 7
(ANI0)