SH7720 Datasheet, PDF (569/1524 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 14 Timer Unit (TMU)
(3) TCNT Count Timing
1. Internal clock
Set the bits TPSC2 to TPSC0 in TCR to select one of the four internal clocks created by
dividing a peripheral module clock (Pφ/4, Pφ/16, Pφ/64, Pφ/256). Figure 14.4 shows the
timing.
Pφ
Divided
clock
TCNT
input clock
TCNT
N+1
N
N–1
Figure 14.4 Count Timing when Internal Clock is Operating
2. Internal RTC clock
Set the bits TPSC2 to TPSC0 in TCR to select the RTC output clock as a clock for timer.
Figure 14.5 shows the timing.
RTC output
clock
TCNT input
clock
TCNT
N+1
N
N-1
Figure 14.5 Count Timing when RTC Clock is Operating
Rev. 3.00 Jan. 18, 2008 Page 507 of 1458
REJ09B0033-0300