Datasheet

Section 12 8-Bit Timers
Rev. 4.00 Sep 27, 2006 page 367 of 1130
REJ09B0327-0400
12.3.6 Input Capture Operation
TMRX has input capture registers of TICR, TICRR, and TICRF. Narrow pulse width can be
measured with TICRR and TICRF, using one capture operation controlled by the ICST bit in the
TCONRI register of the timer connection. When TMRIX detects a rising and falling edge
successively after the ICST bit has been set to 1, the values of TCNT at that time are transferred to
TICRR and TICRF and ICST bit is cleared to 0.
The TMRIX input signal can be selected by setting other bits in the TCONRI register.
(1) Input capture input timing
Figure 12.9 shows the timing of the input capture operation.
φ
Input capture
signal
TMRIX
TCNTX
TICRR
TICRF
nn
M
mm
n + 1 N N +1
n
N
Figure 12.9 Timing of Input Capture Operation
If the input capture signal enters while TICRR and TICRF are being read, it is internally delayed
one system clock (φ) period. Figure 12.10 shows the timing of this operation.