R01UH0823EJ0100 Rev.1.00
Page 1585 of 1823
Jul 31, 2019
RX23W Group
44. 12-Bit A/D Converter (S12ADE)
44.3.2
Single Scan Mode
44.3.2.1
Basic Operation
In basic operation of single scan mode, A/D conversion is performed once on the analog input of the specified channels
as below.
(1) When the ADCSR.ADST bit is set to 1 (A/D conversion start) by software, synchronous trigger, or asynchronous
trigger input, A/D conversion is performed for ANn channels selected by the ADANSA0 and ADANSA1 registers,
starting from the channel with the smallest number n.
(2) 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).
(3) When A/D conversion of all the selected channels is completed, an S12ADI0 interrupt request is generated if the
ADCSR.ADIE bit is 1 (S12ADI0 interrupt upon scanning completion enabled).
(4) 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.
Figure 44.5
Example of Operation in Single Scan Mode (Basic Operation: AN004, AN005, AN006 Selected)
ADST
A/D conversion
started
Waiting for conversion
Waiting for conversion
Waiting for conversion
A/D conversion 1
Set
*1
(1)
(2)
Stored
Waiting for conversion
A/D conversion result 1
Waiting for conversion
A/D conversion result 2
A/D conversion result 3
A/D conversion time
Scanning performed once
(2)
(2)
(3)
(4)
Waiting for conversion
A/D conversion 2
A/D conversion 3
Stored
Stored
Note 1.
indicates the instruction is executed by software.
S12ADI0
ADDR4
ADDR5
ADDR6
Channel 4
(AN004)
Channel 5
(AN005)
Channel 6
(AN006)