Datasheet

Rev.6.00 Oct.28.2004 page 438 of 1016
REJ09B0138-0600H
Bit 5—Timer Overflow Interrupt Enable (OVIE): Selects whether OVF interrupt requests (OVI) are enabled or
disabled when the OVF flag of TCSR is set to 1.
Bit 5
OVIE Description
0 OVF interrupt requests (OVI) are disabled (Initial value)
1 OVF interrupt requests (OVI) are enabled
Bits 4 and 3—Counter Clear 1 and 0 (CCLR1 and CCLR0): These bits select the method by which TCNT is cleared:
by compare match A or B, or by an external reset input.
Bit 4
CCLR1
Bit 3
CCLR0 Description
0 0 Clear is disabled (Initial value)
1 Clear by compare match A
1 0 Clear by compare match B
1 Clear by rising edge of external reset input
Bits 2 to 0—Clock Select 2 to 0 (CKS2 to CKS0): These bits select whether the clock input to TCNT is an internal or
external clock.
Three internal clocks can be selected, all divided from the system clock (ø): ø/8, ø/64, and ø/8192. The falling edge of the
selected internal clock triggers the count.
When use of an external clock is selected, three types of count can be selected: at the rising edge, the falling edge, and
both rising and falling edges.
Some functions differ between channel 0 and channel 1.
Bit 2
CKS2
Bit 1
CKS1
Bit 0
CKS0 Description
0 0 0 Clock input disabled (Initial value)
1 Internal clock, counted at falling edge of ø/8
1 0 Internal clock, counted at falling edge of ø/64
1 Internal clock, counted at falling edge of ø/8192
1 0 0 For channel 0: count at TCNT1 overflow signal*
For channel 1: count at TCNT0 compare match A*
1 External clock, counted at rising edge
1 0 External clock, counted at falling edge
1 External clock, counted at both rising and falling edges
Note: * If the count input of channel 0 is the TCNT1 overflow signal and that of channel 1 is the TCNT0 compare match
signal, no incrementing clock is generated. Do not use this setting.