RL78/G1P
CHAPTER 9 A/D CONVERTER
R01UH0895EJ0100 Rev.1.00
278
Nov 29, 2019
9.6.8 Hardware trigger no-wait mode (scan mode, one-shot 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
place the system in the hardware trigger standby status (and conversion does not start at this stage). Note that,
while in this status, A/D conversion does not start even if ADCS is set to 1.
<3> If a hardware trigger is input while ADCS = 1, A/D conversion is performed 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.
<4> 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.
<5> After A/D conversion of the four channels ends, the ADCS bit remains set to 1, and the system enters the A/D
conversion standby status.
<6> If a hardware trigger is input during conversion operation, the current A/D conversion is interrupted, and
conversion restarts at the first channel. The partially converted data is discarded.
<7> 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.
<8> 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.
<9> 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. However, the A/D converter does not stop in this status.
<10> When ADCE is cleared to 0 while in the A/D conversion standby status, the A/D converter enters the stop status.
When ADCS = 0, inputting a hardware trigger 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
s
If a standard channel is selected as the analog input channel:
Stabilization wait time = 2
s
Figure 9-24. Example of Hardware Trigger No-Wait Mode (Scan Mode, One-Shot Conversion Mode)
Operation Timing
ADCS is cleared
to 0 during A/D
conversion
operation.
The trigger is not
acknowledged.
ADCS retains
the value 1.
<4>
ANI0 to ANI3
<9>
ADCE
Hardware
trigger
ADCS
ADS
A/D
conversion
status
ADCR,
ADCRH
INTAD
<1> ADCE is set to 1.
<2> ADCS is set to 1.
A hardware trigger
is generated.
A hardware trigger is
generated during A/D
conversion operation.
ADCE is cleared to 0. <10>
The trigger is not
acknowledged.
Trigger
standby
status
ANI4 to ANI7
ADS is rewritten
during A/D
conversion operation.
Conversion is
interrupted
and restarts.
Stop
status
Conversion
standby
Conversion
standby
Conversion
standby
Conversion
standby
Conversion
standby
Data 1
(ANI0)
Data 1
(ANI0)
Data 5
(ANI0)
Data 7
(ANI0)
Data 11
(ANI0)
Data 5
(ANI0)
Data 2
(ANI1)
Data 2
(ANI1)
Data 6
(ANI1)
Data 8
(ANI1)
Data 8
(ANI1)
Data 12
(ANI1)
Data 3
(ANI2)
Data 3
(ANI2)
Data 9
(ANI2)
Data 9
(ANI2)
Data 4
(ANI3)
Data 4
(ANI3)
Data 10
(ANI3)
Data 10
(ANI3)
Data 11
(ANI0)
Data 13
(ANI4)
Data 13
(ANI4)
Data 14
(ANI5)
Data 14
(ANI5)
Data 15
(ANI6)
Data 15
(ANI6)
Data 16
(ANI7)
Data 16
(ANI7)
Data 17
(ANI4)
Data 19
(ANI4)
Data 17
(ANI4)
Data 18
(ANI5)
Data 20
(ANI5)
Data 20
(ANI5)
Data 21
(ANI6)
Stop
status
The interrupt is generated four times.
<3>
<3>
<3>
<5>
<5>
<4>
<4>
<8>
<5>
<3>
<6>
ADCS is overwritten
with 1 during A/D
conversion operation.
<7>
A/D
conversion
ends.
Conversion is
interrupted
and restarts.
Conversion is
interrupted
and restarts.
Conversion is
interrupted.
The interrupt is generated four times.
The interrupt is generated four times.
Data 19
(ANI4)
Data 7
(ANI0)