AT32F425
Series Reference Manual
2022.03.30
Page 191
Ver 2.01
Figure 14-6
General-purpose timer block diagram
Input filter
XOR
DIV Prescaler
Prescaler
C2IRAW
C3IRAW
C4IRAW
C1IFP1
TMRX_CH4
TMRX_CH3
TMRX_CH2
TMRX_CH1
TMRx_CH1
TMRx_CH2
TMRx_CH3
TMRx_CH4
C1INC
+/- CNT counter
Period register
Stop, clear, or up/down
Edge detector
Input filter
CxDT
Input
CxDT
Output
C4ORAW
C3ORAW
C2ORAW
C1ORAW
Output
control
Output
control
Output
control
Output
control
C1OUT
C2OUT
C3OUT
C4OUT
Polarity selection
edge detector
prescaler
IS3
IS2
IS1
IS0
C21FP1
TMRx_EXT
Trigger
control
Slave mode
controller
Encoder
interface
Reset,enable,up/down,count
TRGOUT,to
ADC
C1IRAW
14.2.3 TMR2 and TMR3 functional overview
14.2.3.1 Count clock
The count clock of TMR2~TMR5 can be provided by the internal clock (CK_INT), external clock (external
clock mode A and B) and internal trigger input (ISx)
Internal clock (CK_INT)
By default, the CK_INT divided by a prescaler is used to drive the counter to start counting.
Figure 14-7
Control circuit with CK_INT divided by 1
CK_INT
TMREN
COUNTER
12
11
13
14
15
16
00
01
02
03
04
05
06
07
External clock
(
TRGIN/EXT
)
The counter clock can be provided by two external clock sources, namely, TRGIN and EXT
signals.
When SMSEL=3’111, external clock mode A is selected. Set the STIS[2: 0] bit to select TRGIN signal to
drive the counter to start counting.
When ECMBEN=1,
external clock mode B is selected. The counter starts counting driven by EXT
signal.
Figure 14-8
Block diagram of external clock mode A
EXT
C1IFP2
C1IFP1
C1INC
ISx
CK_DIV
Trigger select
Slave mode
control
External clock
control
CI1RAW
Filter
Edge
detector
C2IF_Rising
C2IF_Falling
Polarity
selection