SAM4L Datasheet, PDF (809/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

ATSAM4L4/L2
A trigger such as an external event or a software trigger can modify CVn at any time. If a trigger
occurs while CVn is incrementing, CVn then decrements. If a trigger is received while CVn is
decrementing, CVn then increments. See Figure 30-10 on page 809.
RC Compare cannot be programmed to generate a trigger in this configuration.
At the same time, RC Compare can stop the counter clock (CMRn.CPCSTOP = 1) and/or dis-
able the counter clock (CMRn.CPCDIS = 1).
Figure 30-9. WAVSEL = 1 Without Trigger
Counter Value
0xFFFF
Counter decremented by compare match
with 0xFFFF
RC
RB
RA
Waveform Examples
TIOB
TIOA
Time
Figure 30-10. WAVSEL = 1 With Trigger
Counter Value
Counter decremented by compare match with 0xFFFF
0xFFFF
Counter decremented by trigger
RC
RB
Counter incremented by trigger
RA
Waveform Examples
TIOB
Time
TIOA
42023C–SAM–02/2013
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