Skip to main content
andreaspiezia9
andreaspiezia9
Associate III
October 18, 2013
Question

Alternate function mapping table

  • October 18, 2013
  • 16 replies
  • 12991 views
Posted on October 18, 2013 at 11:04

Hi all,

at page 135 of 

http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/CD00240193.pdf

, I found a note: ''To know which functions are multiplexed on each GPIO pin, refer to the datasheets.'' But I didn't find the datasheet for 

STM32F303VCT6.

At the end, I need to know which value insert in the registers GPIOx_AFRL and GPIOx_AFRH. 

Can someone help me?

Thanks

#lmgtfy #lmgtfy:-stm32-resources #alternate-function-mapping #stm32f303vct6-alternate-function #goes-to-15
    This topic has been closed for replies.

    16 replies

    Tesla DeLorean
    Tesla DeLorean
    Guru
    October 18, 2013
    Posted on October 18, 2013 at 13:34

    http://www.st.com/web/catalog/mmc/FM141/SC1169/SS1576/LN1531/PF252054

    http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00058181.pdf

    Tips, Buy me a coffee, or three.. PayPal Venmo (See Profile) Up vote any posts that you find helpful, it shows what's working..
      andreaspiezia9
      andreaspiezia9Author
      Associate III
      October 21, 2013
      Posted on October 21, 2013 at 09:29

      Hi Clive,

      thank you.

      But I can't find the table with the values used for GPIOx_AFRL (for pin 0 to 7) and GPIOx_AFRH (for pin 8 to 15) configuration in order to select the appropriate alternate function.

      Probably there is something that I didn't understand. 

      Tesla DeLorean
      Tesla DeLorean
      Guru
      October 21, 2013
      Posted on October 21, 2013 at 15:36

      Click on the ''Pg 43'' link provided, navigate to Page 43, observed the table, AF0=0, AF1=1,..AF15=0xF

      0690X00000605FHQAY.png

      Tips, Buy me a coffee, or three.. PayPal Venmo (See Profile) Up vote any posts that you find helpful, it shows what's working..
      andreaspiezia9
      andreaspiezia9Author
      Associate III
      October 21, 2013
      Posted on October 21, 2013 at 16:15

      Thank you Clive,

      now is clear:

      for selecting the AF1, I need to write 0x00000001 both for GPIOx_AFRL and  GPIOx_AFRH as reported at page 147 of 

      http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/CD00240193.pdf

      Tesla DeLorean
      Tesla DeLorean
      Guru
      October 21, 2013
      Posted on October 21, 2013 at 16:26

      You might want to select the Reference Manual for your part, RM0316

      http://www.st.com/st-web-ui/static/active/en/resource/technical/document/reference_manual/DM00043574.pdf

      Tips, Buy me a coffee, or three.. PayPal Venmo (See Profile) Up vote any posts that you find helpful, it shows what's working..
      andreaspiezia9
      andreaspiezia9Author
      Associate III
      November 15, 2013
      Posted on November 15, 2013 at 10:13

      Thanks

      wohler
      wohler
      Visitor II
      December 10, 2013
      Posted on December 10, 2013 at 03:41

      I'm also having difficulty locating such a table for the STM32L152xB. The datasheet has a list of functions for each pin, but no table of how they are mapped to the AFRL/H. Any thoughts?

      Tesla DeLorean
      Tesla DeLorean
      Guru
      December 10, 2013
      Posted on December 10, 2013 at 04:27

      I'm also having difficulty locating such a table for the STM32L152xB. The datasheet has a list of functions for each pin, but no table of how they are mapped to the AFRL/H. Any thoughts?

      http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00277537.pdf

      AFRL describes pins 0-7, AFRH pins 8-15. Each pin source is described by 4-bits, 8x4 = 32-bits in the AFRL/AFRH. The source AFIO[0..15] represents the 4-bit encoding.

      Tips, Buy me a coffee, or three.. PayPal Venmo (See Profile) Up vote any posts that you find helpful, it shows what's working..
      ashish
      ashish
      Visitor II
      December 11, 2013
      Posted on December 11, 2013 at 14:41

      Hello,

      the datasheet you have mentioned above has specified the alternate function  correctly but not in my case of stm32f407vg controller in UM1472 User Manual....its like AF ..

      .USART2_RTS/

      USART4_RX/

      ETH_RMII_REF_CLK/

      ETH_MII_RX_CLK/

      TIM5_CH2/

      TIMM2_CH2/

      ADC123_IN1

      any idea about AFx?

      is it like AF0/AF1/AF2/AF3.........?

      waclawek.jan
      waclawek.jan
      Super User
      December 11, 2013
      Posted on December 11, 2013 at 15:33

      Look into STM32F4xx datasheet, http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00037051.pdf , page 60 and on.

      JW

      Show more replies
      Terms & ConditionsAccessibility statement