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Table 15
Timer Interrupts Overview
Sys. Int.
Interrupt
pending
flag
Mode 1
Mode 2
Mode 3
Mode 4
PWM + Counter
Dual Input Capture +
counter
Dual Counter
Single Capture +
counter
Timer
Int. I
(TnA Int.)
TnAPND
TnCNT1 reload from
TnCRA
TnCNT1 reload from
TnCRB
N/A
TnCNT2 underflow
Input capture on TnA
transition
Input Capture on TnB
transition
TnCNT1 underflow
TnCNT2 underflow
TnCNT1 reload from
TnCRA
N/A
TnCNT1 reload from
TnCRA
Input Capture on TnB
transition
N/A
TnCNT2 underflow
TnBPND
TnCPND
TnDPND
N/A
TnCNT2 reload from
TnCRB
Timer
Int. II
(TnB Int.)
Table 16
Timer I/O Functions
I/O
TnAEN
TnBEN
Mode 1
Mode 2
Mode 3
Mode 4
PWM + Counter
Dual Input Capture +
counter
Dual Counter
Single Capture +
counter
TnA
TnAEN=0
TnBEN=X
TnAEN=1
TnBEN=X
No Output
Capture TnCNT1 into
TnCRA
Capture TnCNT1 into
TnCRA and preset
TnCNT1
Capture TnCNT1 into
TnCRB
Capture TnCNT1 into
TnCRB and preset
TnCNT1
No Output toggle
No Output toggle
Toggle Output on
underflow of TnCNT1
Toggle Output on
underflow of TnCNT1
Toggle Output on
underflow of TnCNT1
TnB
TnAEN=X
TnBEN=0
TnAEN=X
TnBEN=1
Ext. Event or Pulse
Accumulate Input
Ext. Event or Pulse
Accumulate Input
Ext. Event or Pulse
Accumulate Input
Ext. Event or Pulse
Accumulate Input
Capture TnCNT2 into
TnCRB
Capture TnCNT2 into
TnCRB and preset
TnCNT2