cancel
Showing results for 
Search instead for 
Did you mean: 

Do I have to remap I2C1 when the FSMC was used?

jfong
Associate II
Posted on July 03, 2010 at 09:51

Do I have to remap I2C1 when the FSMC was used?

#afio-i2c1-fsmc
13 REPLIES 13
swhite2
Associate III
Posted on May 17, 2011 at 13:57

Looking at the code in  GPIO_PinRemapConfig() (stm32f10x_gpio.c file) you see

  if((GPIO_Remap & 0x80000000) == 0x80000000)

  {

    AFIO->MAPR2 = tmpreg;

  }

  else

  {

    AFIO->MAPR = tmpreg;

  } 

Looking in stm32f10x_gpio.h you see a bunch of remap definitions for the GPIO_Remap argument but only these ones have the MSB set.

#define GPIO_Remap_TIM15            ((uint32_t)0x80000001)  /*!< TIM15 Alternate Function mapping (only for Value line devices) */

#define GPIO_Remap_TIM16            ((uint32_t)0x80000002)  /*!< TIM16 Alternate Function mapping (only for Value line devices) */

#define GPIO_Remap_TIM17            ((uint32_t)0x80000004)  /*!< TIM17 Alternate Function mapping (only for Value line devices) */

#define GPIO_Remap_CEC              ((uint32_t)0x80000008)  /*!< CEC Alternate Function mapping (only for Value line devices) */

#define GPIO_Remap_TIM1_DMA         ((uint32_t)0x80000010)  /*!< TIM1 DMA requests mapping (only for Value line devices) */

#define GPIO_Remap_TIM9             ((uint32_t)0x80000020)  /*!< TIM9 Alternate Function mapping (only for XL-density devices) */

#define GPIO_Remap_TIM10            ((uint32_t)0x80000040)  /*!< TIM10 Alternate Function mapping (only for XL-density devices) */

#define GPIO_Remap_TIM11            ((uint32_t)0x80000080)  /*!< TIM11 Alternate Function mapping (only for XL-density devices) */

#define GPIO_Remap_TIM13            ((uint32_t)0x80000100)  /*!< TIM13 Alternate Function mapping (only for XL-density devices) */

#define GPIO_Remap_TIM14            ((uint32_t)0x80000200)  /*!< TIM14 Alternate Function mapping (only for XL-density devices) */

#define GPIO_Remap_FSMC_NADV        ((uint32_t)0x80000400)  /*!< FSMC_NADV Alternate Function mapping (only for XL-density devices) */

This suggests that only the Value Line and XL families have the AFIO_MAPR2 register. Also the NAVD remap definition has the comment ''only for XL-density devices''.

daviddavid92
Associate II
Posted on May 17, 2011 at 13:57

So it looks like a cockup in earlier devices that has been fixed with this new register in XL devices.....

Chris.

swhite2
Associate III
Posted on May 17, 2011 at 13:57

The technical term for ''cockup'' is ''undocumented feature'' :) That applies to both hardware and firmware.

jfong
Associate II
Posted on May 17, 2011 at 13:57

    So I have to remap the I2C1, or using the software simulated I2C1, to avoid this pin-conflict problem on the 103ZE.