Renesas SH7709S Manual Do Utilizador
Rev. 5.00, 09/03, page 402 of 760
Auto-Reload Count Operation: Figure 12.3 shows the TCNT auto-reload operation.
TCNT value
TCOR
H'00000000
STR0
−
STR2
UNF
TCOR value set to
TCNT during underflow
TCNT during underflow
Time
Figure 12.3 Auto-Reload Count Operation
TCNT Count Timing:
•
Internal Clock Operation: Set the TPSC2–TPSC0 bits in TCR to select whether peripheral
module clock P
module clock P
φ
or one of the four internal clocks created by dividing it is used (P
φ
/4, P
φ
/16,
P
φ
/64, P
φ
/256). Figure 12.4 shows the timing.
P
φ
Internal
clock
TCNT
input clock
TCNT
N + 1
N
N
−
1
Figure 12.4 Count Timing when Operating on Internal Clock