R01UH0823EJ0100 Rev.1.00
Page 1584 of 1823
Jul 31, 2019
RX23W Group
44. 12-Bit A/D Converter (S12ADE)
44.3
Operation
44.3.1
Scanning Operation
In scanning, A/D conversion is performed sequentially on the analog inputs of the specified channels.
A scan conversion is performed in three operating modes: single scan mode, continuous scan mode, and group scan
mode. Also, conversion modes are divided into high-speed conversion mode and normal conversion mode. In single scan
mode, one or more specified channels are scanned once. In continuous scan mode, one or more specified channels are
scanned repeatedly until the ADCSR.ADST bit is cleared to 0 from 1 by software. In group scan mode, the selected
channels of group A and the selected channels of group B are scanned once after starting to be scanned according to the
respective synchronous trigger.
In single scan mode and continuous scan mode, A/D conversion is performed for ANn channels selected by the
ADANSA0 and ADANSA1 registers, starting from the channel with the smallest number n. In group scan mode, A/D
conversion is performed for ANn channels of group A and group B selected by the ADANSA0, ADANSA1, ADANSB0,
and ADANSB1 registers, respectively, starting from the channel with the smallest number n.
When self-diagnosis is selected, it is executed once at the beginning of each scan and one of the three voltages internally
generated in the 12-bit A/D converter is converted.
When performing A/D conversion of the temperature sensor output or internal reference voltage, execute scanning
individually.
Double trigger mode is to be used with single scan mode or group scan mode. With double trigger mode being enabled,
A/D conversion data of a channel selected by the ADCSR.DBLANS[4:0] bits is duplicated only if the conversion is
started by the synchronous trigger selected by the ADSTRGR.TRSA[5:0] bits.