Question

On STM32L4, some timers have a single timer counter, a single ARR, but four different CCRs (i.e., the timer has four output channels, with one dedicated CCR for each channel). Which of the following statements is FALSE? Choose only one...

O We can generate four timer outputs. However, these timer outputs have exactly the same period.
O These four outputs can be left-edge-aligned, center aligned, and right-edge- aligned, determined by the timer counting mode and the timer output mode.
O The output polarity (active high or active low) can be independently programmed.
O Each timer channel its own dedicated interrupt service routine handler.

Answer 1

The FALSE statement is that each timer channel has its own dedicated interrupt service routine handler, as multiple channels may share the same ISR on the STM32L4.

Step-by-step explanation:

The statement that is FALSE regarding an STM32L4 timer with a single timer counter (ARR), and four Capture/Compare Registers (CCRs) is: "Each timer channel has its own dedicated interrupt service routine handler." While an STM32L4 timer typically has multiple output channels, the interrupt handling for each of those channels is not necessarily dedicated to distinct interrupt service routines (ISRs). Instead, multiple channels can share the same ISR, with the specific channel triggering the interrupt identified within the shared routine.

The other statements provided are true: Timers can generate four outputs with the same period; the outputs' alignment can be determined by the timer counting mode and output mode; and the output polarity can be independently programmed for each channel.