Channel Selection And Self-Diagnosis (Without Channel-Dedicated Sample-And-Hold Circuits) - Renesas RX100 Series User Manual

RX13T Group
26.3.2.3 Channel Selection and Self-Diagnosis (Without Channel-Dedicated Sample-
and-Hold Circuits)
When channels and self-diagnosis are selected, A/D conversion is performed once for the reference voltage supplied to
the 12-bit A/D converter as below. After that, A/D conversion is performed only once on the analog input of the selected
channels.
(1) A/D conversion for self-diagnosis is started when the ADCSR.ADST bit is set to 1 (A/D conversion start) by
software, or synchronous or asynchronous trigger input.
(2) When A/D conversion for self-diagnosis is completed, A/D conversion result is stored into the A/D self-diagnosis
data register (ADRD), and A/D conversion is performed for ANn channels selected by the ADANSA0 register,
starting from the channel with the smallest number n.
(3) Each time A/D conversion of a single channel is completed, the A/D conversion result is stored into the
corresponding A/D data register (ADDRy).
(4) When A/D conversion of all the selected channels is completed, a scan end interrupt request is generated if the
ADCSR.ADIE bit is 1 (interrupt generation upon scanning completion enabled).
(5) The ADST bit remains 1 (A/D conversion start) during A/D conversion, and is automatically cleared to 0 when A/D
conversion of all the selected channels is completed. Then the 12-bit A/D converter enters a wait state.
A/D conversion
started
ADST
Reference
voltage
Waiting for conversion
(x0, x½, x1)
Channel 0
Waiting for conversion
(AN000)
Channel 3
Waiting for conversion
(AN003)
ADRD
ADDR0
ADDR3
Scan end
interrupt
Note 1.
Figure 26.4 Example of Operation in Single Scan Mode
(Basic Operation: AN000, AN003 Selected + Self-Diagnosis)
R01UH0822EJ0100 Rev.1.00
Jul 31, 2019
Scanning performed once
*1
Set
(1)
A/D conversion time
A/D conversion for
self-diagnosis
A/D conversion 1
Stored (2)
A/D conversion for self-diagnosis result
indicates the instruction is executed by software.
(5)
Waiting for conversion
A/D conversion 2
Stored (3)
A/D conversion result 1
Stored (3)
A/D conversion result 2
(4)
Interrupt generated
26. 12-Bit A/D Converter (S12ADF)
Waiting for conversion
Waiting for conversion
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