SH7708 Datasheet, PDF (325/625 Pages) Renesas Technology Corp – SuperH™ RISC engine

Pφ
External
clock input
pin
TCNT
input clock
TCNT
N+1
N
N–1
Figure 11.5 Count Timing when External Clock Is Operating (Both Edges
Detected)
• On-Chip RTC Clock Operation: Set the TPSC2–TPSC0 bits in TCR to select the on-chip
RTC clock as the timer clock. Figure 11.6 shows the timing.
RTC output
clock
TCNT input
clock
TCNT N + 1
N
N–1
Figure 11.6 Count Timing when On-Chip RTC Clock Is Operating
Input Capture Function: Channel 2 has an input capture function (figure 11.7). When using
the input capture function, set the TCLK pin to input mode with the TCOE bit in the timer
output control register (TOCR) and set the timer operation clock to internal clock or on-chip RTC
clock with the TPCS2–TPCS0 bits in the timer control register (TCR). Also, designate use of the
input capture function and whether to generate interrupts on using it with the IPCE1–IPCE0 bits
in TCR, and designate the use of either the rising or falling edge of the TCLK pin to set the timer
counter (TNCT) value into the input capture register (TCPR) with the CKEG1–CKEG0 bits in
TCR.
The input capture function cannot be used in standby mode.
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