R01UH0823EJ0100 Rev.1.00
Page 655 of 1823
Jul 31, 2019
RX23W Group
24. Port Output Enable 2 (POE2a)
24.3.3
High-Impedance Control Using Registers
The high-impedance of the MTU complementary PWM output and MTU0 pins can be directly controlled by writing to
the software port output enable register (SPOER).
Setting the SPOER.CH34HIZ bit to 1 places the MTU complementary PWM output pins (MTU3 and MTU4) specified
by the POECR2 register in the high-impedance.
Setting the SPOER.CH0HIZ bit to 1 places the MTU0 output pins specified by port output enable control register 1
(POECR1) in the high-impedance.
24.3.4
High-Impedance Control on Detection of Stopped Oscillation
When the oscillation stop detection function in the clock generation circuit detects stopped oscillation while the
ICSR3.OSTSTE bit is 1, the MTU complementary PWM output pins specified by the POECR2 register and the MTU0
output pins specified by the POECR1 register are placed in the high-impedance.
24.3.5
High-Impedance Control in Response to Receiving an Event Signal from the
ELC
The MTU complementary PWM output and MTU0 pins can be placed in the high-impedance state in response to an
event signal from the ELC.
To control the high-impedance state of the MTU complementary PWM output and MTU0 pins, preset the corresponding
register (POECR1 or POECR2) to enable the high-impedance state. When an event signal is received from the ELC, the
corresponding bit (SPOER.CH0HIZ or SPOER.CH34HIZ) is set to 1, and the MTU complementary PWM output pins or
MTU0 pins are placed in the high-impedance state.
24.3.6
Release from the High-Impedance
Pins for complementary PWM output from MTU and pins for MTU0 which have been placed in the high-impedance due
to input-level detection can be released from that state by either returning them to their initial state with a reset or
clearing all of the ICSR1.POE3F, POE1F and POE0F flags and the ICSR2.POE8F flag. Note, however, that when low-
level sampling is selected by the ICSR1.POE3M[1:0], POE1M[1:0], and POE0M[1:0] bits, and the ICSR2.POE8M[1:0]
bits, if a high level is being input to the corresponding pin from among POE0#, POE1#, POE3# and POE#8 but has not
yet been detected, writing 0 to the flag is ignored (the flag is not cleared).
MTU complementary PWM output pins which have been placed in the high-impedance due to output-level comparison
can be released from that state by either returning them to their initial state with a reset or clearing the OCSR1.OSF1
flag. Note, however, that if the inactive level is not yet being output from the MTU complementary PWM output pins,
writing 0 to the flag is ignored (the flag is not cleared). Inactive-level outputs can be obtained by setting the MTU
registers.
For MTU complementary PWM output pins and pins for MTU0 that have been placed in the high-impedance because
oscillation by the clock generation circuit has stopped, clearing the ICSR3.OSTSTF or ICSR3.OSTSTE bit releases the
pins from the high-impedance.
For MTU complementary PWM output pins and pins for MTU0 that have been placed in the high-impedance by the
SPOER.CH34HIZ or SPOER.CH0HIZ bit, clearing the corresponding bits (SPOER.CH34HIZ and SPOER.CH0HIZ)
releases the pins from the high-impedance.