STM32F103C8 Peripheral Alternate Function

[markbell9]

Posted on June 14, 2012 at 15:55

On the STM32F103C8 chip I can use the PA9 default alternate function to use either USART1_TX or TIM1_CH2 on that pin depending upon which peripheral is enabled.

If both peripherals are enabled and I am using PA9 as USART1_TX, does this preclude me from using TIM_CH1, TIM_CH3, or TIM_CH4?

This assumes that TIM_CH2 is disabled: TIM1 MOE =1 OSSR = x CC2E = 0 CC2NE = 0 I pretty sure the answer is ''Yes'', but would like confirmation. Thank you. #stm32

[raptorhal2]

Posted on June 14, 2012 at 16:34

Each pin is independent as to alternate function, so the other timer channels are available.

Cheers, Hal

[Andrew Neil]

Posted on June 14, 2012 at 19:43

Many Alternate Functions can be ''re-mapped'' onto different pins...

[Tesla DeLorean]

Posted on June 14, 2012 at 20:04

Many Alternate Functions can be ''re-mapped'' onto different pins...

And sometimes must be otherwise pins clash. This is the case for one of the CAN outputs and a USART CTS or RTS pin. It's in the errata now, but banged my head on it with a 103 design. You need to remap the CAN off in the weeds. PA11 or PA12 as I recall. Definitely review the errata as you floor plan the pin escape of your design.