R01UH0823EJ0100 Rev.1.00
Page 1527 of 1823
Jul 31, 2019
RX23W Group
43. Capacitive Touch Sensing Unit (CTSU)
(2) Measurement data transfer request interrupt (CTSURD)
Set DTC or ICU transfer corresponding to the CTSURD interrupt in advance. The CTSURD interrupt is output when
Status 5 transitions to Status 1. Read the measurement result from the CTSUSC and CTSURC counters (
Figure 43.20
Example of DTC Transfer Operation Using CTSURD Interrupt
The measurement result registers (CTSUSC and CTSURC counters) used as transfer sources are allocated at sequential
addresses. Set the operation at interrupt generation as shown below:
Transfer source address: Address of the CTSUSC counter
Handling at the transfer source address: Transfer 2-byte data twice by a single interrupt. (The start address is fixed.)
Transfer destination address: CTSUSC counter data storage address for the minimum channel in the setting data
stored in the RAM.
Handling at the transfer destination address: Transfer 2-byte data twice by a single interrupt. (The start address is
continued from the previous interrupt handling.)
Number of transfers by an interrupt: Specify the number of measurements.
(3) Measurement end interrupt (CTSUFN)
When all channels are measured, an interrupt is generated when Status 1 transitions to Status 0. Use software to confirm
the overflow flags (CTSUST.CTSUSOVF and CTSUROVF flags) and read the measurement results to determine
whether or not the electrode is touched.
Interrupt requests are accepted or disabled in the interrupt control block.
Channel 2
CTSUSC
000A 0918h
000A 091Ah
CTSURC
Write the measurement result of
each channel
CTSU registers
Transfer
Channel 0
Channel 1
RAM
First CTSURD interrupt
Second CTSURD interrupt