SH7080_09 Datasheet, PDF (684/1622 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family

Section 11 Multi-Function Timer Pulse Unit 2 (MTU2)
11.7.3 Caution on Period Setting
When counter clearing on 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:
• Channels 0 to 4
MPφ
f=
(N + 1)
• Channel 5
MPφ
f=
N
Where
f:
Counter frequency
MPφ: MTU2 peripheral clock operating frequency
N: TGR set value
11.7.4 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 11.121 shows the timing in this case.
MPφ
TCNT write cycle
T1 T2
Address
TCNT address
Write signal
Counter clear
signal
TCNT
N
H'0000
Figure 11.121 Contention between TCNT Write and Clear Operations
Rev. 4.00 Dec. 15, 2009 Page 624 of 1558
REJ09B0181-0400