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CHAPTER 6
16-BIT TIMER/EVENT COUNTER 0
User’s Manual U12790EJ2V0UD
(8) Conflicting operations
(a) If the read period and capture trigger input conflict
If the read period and inputting a capture trigger conflict while 16-bit capture/compare registers 00 and
01 (CR00 and CR01) are used as capture registers, the capture operation takes precedence and the read
data is undefined. However, the interrupt request flags (TMIF00/TMIF01) are set when the valid edge
is detected.
(b) If the match timing of the write period and TM0 conflict
When 16-bit capture/compare registers 00 and 01 (CR00, CR01) are used as capture registers, because
match detection cannot be performed correctly if the match timing of the write period and 16-bit timer
counter 0 (TM0) conflict, do not write to CR00 and CR01 close to the match timing.
(9) Timer operation
<1> Even if 16-bit timer counter 0 (TM0) is read, its value is not captured to 16-bit capture/compare register
01 (CR01).
<2> While the timer is stopped, signals input to the TI00 and TI01 pins are not accepted regardless of the
operating mode of the CPU.
<3> The one-shot pulse output operates correctly only in the free-running mode or the mode in which TM0
is cleared and started at the valid edge of TI00. In the mode in which TM0 is cleared and started on
a match between TM0 and CR00, the one-shot operation cannot be performed because TM0 does not
overflow.
(10) Capture operation
<1>
If the TI00 valid edge is specified as the count clock, a capture operation by the capture register specified
as the trigger for TI00 is not possible.
<2>
If both the rising and falling edges are selected as the valid edges of TI00, CR00 does not perform a capture
operation.
<3>
To ensure the reliability of the capture operation, the capture trigger requires a pulse longer than two cycles
of the count clock selected by prescaler mode register 0 (PRM0).
Figure 6-36. CR01 Capture Operation with Rising Edge Specified
<4>
The capture operation is performed at the fall of the count clock. Interrupt request input (INTTM00,
INTTM01), however, occurs at the rise of the next count clock.
Count clock
TM0
TI00
Rising edge detection
CR01
INTTM01
N–3N–2N–1
N
N+1
N