Datasheet
Section 13 8-Bit Timers (TMR) 
Page 832 of 1384    R01UH0310EJ0500 Rev. 5.00 
 Sep 25, 2012 
H8S/2426, H8S/2426R, H8S/2424 Group
13.3.5  Timer Counter Control Register (TCCR) 
TCCR selects the TCNT internal clock source and controls the external reset input. 
Bit  Bit Name  Initial Value  R/W  Description 
7 to 4  ⎯ All 0  R Reserved 
These bits are always read as 0 and cannot be 
modified. 
3  TMRIS  0  R/W  Timer Reset Input Select 
Selects the external reset input, in combination 
with the CCLR1 and CCLR0 bits in TCR. See 
table 13.2. 
2  ⎯ 0  R Reserved 
This bit is always read as 0 and cannot be 
modified. 
1 
0 
ICKS1 
ICKS0 
0 
0 
R/W 
R/W 
Internal Clock Select 1, 0 
These bits select the internal clock source, in 
combination with the CKS2 to CKS0 bits in TCR. 
See table 13.3. 
Table 13.2  Reset Input to TCNT and Clearing Condition 
TCR TCCR 
Bit 1 
CCLR1 
Bit 0 
CCLR0 
Bit 3 
TMRIS 
Description 
0  0  0  Clearing is disabled 
0  1  0  Clear by compare match A 
1  0  0  Clear by compare match B 
1  1  0  Clear by rising edge of external reset input 
0  0  1  Clear by both rising and falling edges of external reset input 
0  1  1  Clear by falling edge of external reset input 
1  0  1  Clear by low level of external reset input 
1  1  1  Clear by high level of external reset input 










