Conversion On External Trigger And Trigger Polarity; Table 76. Configuring The Trigger Polarity; Table 77. External Trigger For Regular Channels - ST STM32F423 Reference Manual

RM0430
13.6

Conversion on external trigger and trigger polarity

Conversion can be triggered by an external event (e.g. timer capture, EXTI line). If the
EXTEN[1:0] control bits (for a regular conversion) or JEXTEN[1:0] bits (for an injected
conversion) are different from "0b00", then external events are able to trigger a conversion
with the selected polarity.
and JEXTEN[1:0] values and the trigger polarity.
Trigger detection disabled
Detection on the rising edge
Detection on the falling edge
Detection on both the rising and falling edges
Note: The polarity of the external trigger can be changed on the fly.
The EXTSEL[3:0] and JEXTSEL[3:0] control bits are used to select which out of 16 possible
events can trigger conversion for the regular and injected groups.
Table 77
TIM1_CH1 event
TIM1_CH2 event
TIM1_CH3 event
TIM2_CH2 event
TIM2_CH3 event
TIM2_CH4 event
TIM2_TRGO event
TIM3_CH1 event
TIM3_TRGO event
TIM4_CH4 event
TIM5_CH1 event
TIM5_CH2 event
TIM5_CH3 event
TIM8_CH1 event
TIM8_TRGO event
EXTI line11
Table 76

Table 76. Configuring the trigger polarity

Source
gives the possible external trigger for regular conversion.

Table 77. External trigger for regular channels

Source
Internal signal from on-chip timers
External pin
provides the correspondence between the EXTEN[1:0]
Type
RM0430 Rev 8
Analog-to-digital converter (ADC)
EXTEN[1:0] / JEXTEN[1:0]
00
01
10
11
EXTSEL[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
345/1324
365