About the timer signals in the STM32 data sheet

I've been working on a timer recently. When I read the instructions, it was like reading a book written in heaven. I didn't understand where the problem was. I didn't understand how many signals came from. So I took some time to sort it out. I opened the overall block diagram in the STM32 data sheet. Damn, I was dazzled again. First of all, we can see that this diagram has two parts, one is the clock source, and the other is the input and output. The clock source counts to the CNT counter, and then records or compares according to the capture compare register. There are different configurations for recording or comparing. First is the TI signal TI1 TI2 TI3 TI4: This signal is an external signal, which is a signal directly connected to the pin. There is another problem in the diagram. TI1 can be triggered by an external signal of the first channel, or it can be set to trigger the first channel, the second channel, and the third channel XOR. The external signal is sent to the filter and edge detector. [page] TIxFP triggers a valid signal.   TI1FP1 TI1FP2 TI2FP1 TI2FP2 TI3FP3 TI3FP4 TI4FP3 TI4FP4: This is a trigger valid signal. Since the signal directly connected to the pin can be set to high or low edge trigger, after setting, TIxFP is the mark corresponding to whether the signal is valid. ICx mapping signal IC1 IC2 IC3 IC4: channel valid signal, in front of it are TIxFP and TRC signals. It can be seen that TI1FP and TI2FP can correspond to IC1 and IC2, TI3FP and TI4FP can correspond to IC3 and IC4, so that one TIxFP signal can correspond to two ICx or two channels. In this way, PWM input can be realized, and one can calculate the period and the other can calculate the duty cycle. ICx signal is sent to the prescaler Channel interrupt and DMA output signal CC1I CC2I CC3I CC4I: After the ICx signal passes through the prescaler, it can be configured to generate interrupt or DMA output. Prescaler counting signal IC1PS IC2PS IC3PS IC4PS: After the ICx signal passes through the prescaler, it can enter the CCRx counting register. At this time, the CCR can be read in conjunction with the interrupt. OC1REF output valid signal OC1REF OC2REF OC3REF OC4REF: The first output signal when comparing output or PWM output. This signal can be turned into an effective level output to the pin after configuring the high and low levels. Comparison output PWM output level OC1 OC1N OC2 OC2N OC3 OC3N OC4: Signal output to the pin Brake input pin signal BRK Brake input pin signal, after the pin is input, enters the polarity selection. Brake signal BI: Brake signal, after the polarity selection signal is ORed with the clock failure signal, the brake valid signal is obtained. To drive the brake. Update time u Update event signal, generated by software event register or counter overflow. Event update interrupt UI: event update interrupt signal External ETR trigger pin signal ETR: trigger timer dedicated trigger pin connected to external pin ETR signal after edge pre-scaling ETRP: ETR signal after edge pre-scaling ETR valid signal after filtering ETRF: ETRP valid signal after filtering, polarity, and edge Internal trigger ITRx channel signal ITR0 ITR1 ITR2 ITR3: The trigger can be generated by other internal timers, and the timer triggers of timer 1 and timer 8 are different. In the timer chapter table 74 in the data manual, it is reflected that the ITR trigger signal ITRx is set to generate a trigger signal. Enter the next link. TI1 edge detector TI1F_ED: TI1 edge detection signal, in Hall sensor mode, will detect the change of TI1, from the input is TI1F_ED. Whenever one of the three inputs changes, the counter starts counting from 0 again. This generates a time base triggered by any change in the Hall input. TRC: The trigger signal issued after selecting the TI1 edge and internal trigger through the selector. TRGI: Final trigger input. TGI: Trigger input interrupt bit TRGO: Trigger output. As the master mode to send out the trigger signal to control other timers, it should be connected to the ITRx of other timers.