Figure 326. Measuring Time Interval Between Edges On 2 Signals; Timer Input Xor Function (Tim15 Only) - ST STM32L4x6 Reference Manual

General-purpose timers (TIM15/16/17)
28.4.16

Timer input XOR function (TIM15 only)

The TI1S bit in the TIMx_CR2 register, allows the input filter of channel 1 to be connected to
the output of a XOR gate, combining the two input pins TIMx_CH1 and TIMx_CH2.
The XOR output can be used with all the timer input functions such as trigger or input
capture. It is useful for measuring the interval between the edges on two input signals, as
shown in
960/1693
Figure 326.

Figure 326. Measuring time interval between edges on 2 signals

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