HD6417615 Hitachi Semiconductor, HD6417615 Datasheet - Page 715

• Manufacturer Part Number: HD6417615
• Description: Hardware Manual
• Manufacturer: Hitachi Semiconductor

Caution on Period Setting: When counter clearing by compare match is set, TCNT is cleared in
the final state in which it matches the TGR value (the point at which the count value matched by
TCNT is updated). Consequently, the actual counter frequency is given by the following formula:
Where
Contention between TCNT Write and Clear Operations: If the counter clear signal is
generated in the T2 state of a TCNT write cycle, TCNT clearing takes precedence and the TCNT
write is not performed.
Figure 16.45 shows the timing in this case.
P
Address
Write signal
Counter clear
signal
TCNT
f =
f
P : Peripheral module clock
N : TGR set value
Figure 16.45 Contention between TCNT Write and Clear Operations
(N + 1)
: Counter frequency
P
N
TCNT write cycle
TCNT address
T1
T2
H'0000
703