HD64F2149 Datasheet, PDF (389/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

Table 12.6 TMRY 8-Bit Timer Interrupt Sources
Interrupt source
CMIA
CMIB
OVI
Description
Requested by CMFA
Requested by CMFB
Requested by OVF
DTC Activation
Possible
Possible
Not possible
Interrupt Priority
High
Low
12.5 8-Bit Timer Application Example
In the example below, the 8-bit timer is used to generate a pulse output with a selected duty cycle,
as shown in figure 12.12. The control bits are set as follows:
• In TCR, CCLR1 is cleared to 0 and CCLR0 is set to 1 so that the timer counter is cleared by a
TCORA compare-match.
• In TCSR, bits OS3 to OS0 are set to B'0110, causing 1 output at a TCORA compare-match and
0 output at a TCORB compare-match.
With these settings, the 8-bit timer provides output of pulses at a rate determined by TCORA with
a pulse width determined by TCORB. No software intervention is required.
H'FF
TCORA
TCORB
H'00
TCNT
Counter clear
TMO
Figure 12.12 Pulse Output (Example)
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