R01UH0823EJ0100 Rev.1.00
Page 1598 of 1823
Jul 31, 2019
RX23W Group
44. 12-Bit A/D Converter (S12ADE)
The following is an example of a rescanning operation in which a group B trigger is input during A/D conversion on
group A. In this example, channels 1 to 3 are selected for group A and channel 0 is selected for group B when operation
on group A is given priority (ADGSPCR.GBRSCN = 1, ADGSPCR.GBRP = 0).
(1) When input of a trigger for group A sets the ADCSR.ADST bit to 1 (A/D conversion start), conversion for the ANn
channels selected in the ADANSA0 and ADANSA1 registers, starting from the channel with the smallest number n.
(2) On completion of A/D conversion on a single channel, the result is stored in the corresponding A/D data register
(ADDRy).
(3) If a group B trigger is input during A/D conversion on group A, A/D conversion on group B can be performed after
the A/D conversion on group A is completed. (However, if group A triggers are input continuously, the scan
operation on group B is canceled by group A and is not performed.)
(4) On completion of the A/D conversion on the group A, an S12ADI0 interrupt request is generated if the setting of the
ADCSR.ADIE bit is 1 (S12ADI0 interrupt upon scanning completion enabled).
(5) On completion of the A/D conversion on the group A, activation of group B for rescanning sets the ADCSR.ADST
bit to 1 automatically.
After that, conversion for the ANn channels of group B selected in the ADANSB0 and ADANSB1 registers,
starting from the channel with the smallest number n.
(6) On completion of A/D conversion on a single channel, the result is stored in the corresponding A/D data register
(ADDRy).
(7) On completion of the rescanning operation on the group B, a GBADI interrupt request is generated if the setting of
the ADCSR.GBADIE bit is 1 (GBADI interrupt upon scanning completion enabled).
(8) The ADST bit retains the value 1 (A/D conversion start) during A/D conversion and is automatically cleared on
completion of conversion, after which the A/D converter enters a wait state.