Datasheet
Section 12 8-Bit Timers 
Rev. 6.00 Mar. 18, 2010 Page 452 of 982 
REJ09B0054-0600 
Bit Bit Name 
Initial 
Value 
R/W Description 
3 
2 
OS3 
OS2 
0 
0 
R/W 
R/W 
Output Select 3 and 2 
These bits specify how the timer output level is to be 
changed by a compare-match B of TCORB and 
TCNT. 
00: No change when compare-match B occurs 
01: 0 is output when compare-match B occurs 
10: 1 is output when compare-match B occurs 
11: Output is inverted when compare-match B occurs 
(toggle output) 
1 
0 
OS1 
OS0 
0 
0 
R/W 
R/W 
Output Select 1 and 0 
These bits specify how the timer output level is to be 
changed by a compare-match A of TCORA and 
TCNT. 
00: No change when compare-match A occurs 
01: 0 is output when compare-match A occurs 
10: 1 is output when compare-match A occurs 
11: Output is inverted when compare-match A occurs 
(toggle output) 
Notes:  1.  Not available in the H8S/2237 Group and H8S/2227 Group. 
  2.  Only 0 can be written to this bit, to clear the flag. 
12.4 Operation 
12.4.1 Pulse Output 
Figure 12.2 shows an example of arbitrary duty pulse output. 
1.  Set TCR in CCR1 to 0 and CCLR0 to 1 to clear TCNT by a TCORA compare-match. 
2.  Set OS3 to OS0 bits in TCSR to B'0110 to output 1 by a compare-match A and 0 by compare-
match B. 
By the above settings, waveforms with the cycle of TCORA and the pulse width of TCRB can be 
output without software intervention. 










