R01UH0823EJ0100 Rev.1.00
Page 605 of 1823
Jul 31, 2019
RX23W Group
23. Multi-Function Timer Pulse Unit 2 (MTU2a)
23.6.17
Contention between Overflow/Underflow and Counter Clearing
If an overflow/underflow and counter clearing occur simultaneously, the TCNT counter clearing takes precedence and
the corresponding TCIV interrupt is not generated. If an overflow and counter clearing due to an input capture occur
simultaneously, an input capture interrupt signal is output and an overflow interrupt signal is not output.
shows the operation timing when a TGR compare match is specified as the clearing source and the TGR
register is set to FFFFh.
Figure 23.109
Contention between Overflow and Counter Clearing
23.6.18
Contention between TCNT Write Operation and Overflow/Underflow
If TCNT up-count or down-count in a TCNT write cycle and an overflow or an underflow occurs, the TCNT write
operation takes precedence. The corresponding interrupt is not generated.
shows the operation timing when there is contention between TCNT write operation and overflow.
Figure 23.110
Contention between TCNT Write Operation and Overflow
TCNT count clock
TCIV interrupt signal
Counter clear signal
TCNT
Not generated
FFFFh
0000h
PCLK
TCNT
Interrupt signal
PCLK
Not generated
FFFFh
M
TCNT write data
Written by CPU