HD6433044 Datasheet, PDF (349/867 Pages) Hitachi Semiconductor – Hitachi Single-Chip Microcomputer

Counter setup
Select counter clock
1
No
Type of counting?
Yes
Periodic counting
Select counter clear source 2
Free-running counting
Select output compare
register function
3
Set period
4
Start counter
5
Periodic counter
Start counter
5
Free-running counter
Figure 10-14 Counter Setup Procedure (Example)
1. Set bits TPSC2 to TPSC0 in TCR to select the counter clock source. If an external clock
source is selected, set bits CKEG1 and CKEG0 in TCR to select the desired edge(s) of the
external clock signal.
2. For periodic counting, set CCLR1 and CCLR0 in TCR to have TCNT cleared at GRA
compare match or GRB compare match.
3. Set TIOR to select the output compare function of GRA or GRB, whichever was selected in
step 2.
4. Write the count period in GRA or GRB, whichever was selected in step 2.
5. Set the STR bit to 1 in TSTR to start the timer counter.
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