Introduction - If you have any usage issues, please Google them yourself
The source code for the STM32 timer routine use, the main test Timer 2 functions. Development environment realviewMDK set the timer 2 output compare mode, four-channel comparison of each set different values, so generate an interrupt for each channel a different frequency. In the interrupt handler, respectively, the corresponding LED flip, which can be observed four different frequencies of flashing LED. Flicker frequency by approaching slowly: LD5, LD6, LD4, LD3.