2013-10-18 02:04 AM
Hi all,
at page 135 of , 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 forSTM32F303VCT6.
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-152013-12-11 06:33 AM
Look into STM32F4xx datasheet, http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00037051.pdf , page 60 and on.
JW2013-12-11 07:09 AM
the datasheet you have mentioned above has specified the alternate function correctly but not in my case of stm32f407vg controller inUM1472User Manual....its like AF ..
Sometimes I wonder if people here are ********... Yes because they are different bloody parts, try Googling YOUR parthttp://www.st.com/web/catalog/mmc/FM141/SC1169/SS1577/LN11/PF252140
andhttp://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00037pdf
STM32F4xx_DSP_StdPeriph_Lib_V1.2.0\Libraries\STM32F4xx_StdPeriph_Driver\inc\stm32f4xx_gpio.h/** @defgroup GPIO_Alternat_function_selection_define
* @{
*/
/**
* @brief AF 0 selection
*/
#define GPIO_AF_RTC_50Hz ((uint8_t)0x00) /* RTC_50Hz Alternate Function mapping */
#define GPIO_AF_MCO ((uint8_t)0x00) /* MCO (MCO1 and MCO2) Alternate Function mapping */
#define GPIO_AF_TAMPER ((uint8_t)0x00) /* TAMPER (TAMPER_1 and TAMPER_2) Alternate Function mapping */
#define GPIO_AF_SWJ ((uint8_t)0x00) /* SWJ (SWD and JTAG) Alternate Function mapping */
#define GPIO_AF_TRACE ((uint8_t)0x00) /* TRACE Alternate Function mapping */
/**
* @brief AF 1 selection
*/
#define GPIO_AF_TIM1 ((uint8_t)0x01) /* TIM1 Alternate Function mapping */
#define GPIO_AF_TIM2 ((uint8_t)0x01) /* TIM2 Alternate Function mapping */
/**
* @brief AF 2 selection
*/
#define GPIO_AF_TIM3 ((uint8_t)0x02) /* TIM3 Alternate Function mapping */
#define GPIO_AF_TIM4 ((uint8_t)0x02) /* TIM4 Alternate Function mapping */
#define GPIO_AF_TIM5 ((uint8_t)0x02) /* TIM5 Alternate Function mapping */
/**
* @brief AF 3 selection
*/
#define GPIO_AF_TIM8 ((uint8_t)0x03) /* TIM8 Alternate Function mapping */
#define GPIO_AF_TIM9 ((uint8_t)0x03) /* TIM9 Alternate Function mapping */
#define GPIO_AF_TIM10 ((uint8_t)0x03) /* TIM10 Alternate Function mapping */
#define GPIO_AF_TIM11 ((uint8_t)0x03) /* TIM11 Alternate Function mapping */
/**
* @brief AF 4 selection
*/
#define GPIO_AF_I2C1 ((uint8_t)0x04) /* I2C1 Alternate Function mapping */
#define GPIO_AF_I2C2 ((uint8_t)0x04) /* I2C2 Alternate Function mapping */
#define GPIO_AF_I2C3 ((uint8_t)0x04) /* I2C3 Alternate Function mapping */
/**
* @brief AF 5 selection
*/
#define GPIO_AF_SPI1 ((uint8_t)0x05) /* SPI1 Alternate Function mapping */
#define GPIO_AF_SPI2 ((uint8_t)0x05) /* SPI2/I2S2 Alternate Function mapping */
#define GPIO_AF_SPI4 ((uint8_t)0x05) /* SPI4 Alternate Function mapping */
#define GPIO_AF_SPI5 ((uint8_t)0x05) /* SPI5 Alternate Function mapping */
#define GPIO_AF_SPI6 ((uint8_t)0x05) /* SPI6 Alternate Function mapping */
/**
* @brief AF 6 selection
*/
#define GPIO_AF_SPI3 ((uint8_t)0x06) /* SPI3/I2S3 Alternate Function mapping */
#define GPIO_AF_SAI1 ((uint8_t)0x06) /* SAI1 Alternate Function mapping */
/**
* @brief AF 7 selection
*/
#define GPIO_AF_USART1 ((uint8_t)0x07) /* USART1 Alternate Function mapping */
#define GPIO_AF_USART2 ((uint8_t)0x07) /* USART2 Alternate Function mapping */
#define GPIO_AF_USART3 ((uint8_t)0x07) /* USART3 Alternate Function mapping */
#define GPIO_AF_I2S3ext ((uint8_t)0x07) /* I2S3ext Alternate Function mapping */
/**
* @brief AF 8 selection
*/
#define GPIO_AF_UART4 ((uint8_t)0x08) /* UART4 Alternate Function mapping */
#define GPIO_AF_UART5 ((uint8_t)0x08) /* UART5 Alternate Function mapping */
#define GPIO_AF_USART6 ((uint8_t)0x08) /* USART6 Alternate Function mapping */
#define GPIO_AF_UART7 ((uint8_t)0x08) /* UART7 Alternate Function mapping */
#define GPIO_AF_UART8 ((uint8_t)0x08) /* UART8 Alternate Function mapping */
/**
* @brief AF 9 selection
*/
#define GPIO_AF_CAN1 ((uint8_t)0x09) /* CAN1 Alternate Function mapping */
#define GPIO_AF_CAN2 ((uint8_t)0x09) /* CAN2 Alternate Function mapping */
#define GPIO_AF_TIM12 ((uint8_t)0x09) /* TIM12 Alternate Function mapping */
#define GPIO_AF_TIM13 ((uint8_t)0x09) /* TIM13 Alternate Function mapping */
#define GPIO_AF_TIM14 ((uint8_t)0x09) /* TIM14 Alternate Function mapping */
#define GPIO_AF9_I2C2 ((uint8_t)0x09) /* I2C2 Alternate Function mapping (Only for STM32F401xx Devices) */
#define GPIO_AF9_I2C3 ((uint8_t)0x09) /* I2C3 Alternate Function mapping (Only for STM32F401xx Devices) */
/**
* @brief AF 10 selection
*/
#define GPIO_AF_OTG_FS ((uint8_t)0xA) /* OTG_FS Alternate Function mapping */
#define GPIO_AF_OTG_HS ((uint8_t)0xA) /* OTG_HS Alternate Function mapping */
/**
* @brief AF 11 selection
*/
#define GPIO_AF_ETH ((uint8_t)0x0B) /* ETHERNET Alternate Function mapping */
/**
* @brief AF 12 selection
*/
#if defined (STM32F40_41xxx)
#define GPIO_AF_FSMC ((uint8_t)0xC) /* FSMC Alternate Function mapping */
#endif /* STM32F40_41xxx */
#if defined (STM32F427_437xx) || defined (STM32F429_439xx)
#define GPIO_AF_FMC ((uint8_t)0xC) /* FMC Alternate Function mapping */
#endif /* STM32F427_437xx || STM32F429_439xx */
#define GPIO_AF_OTG_HS_FS ((uint8_t)0xC) /* OTG HS configured in FS, Alternate Function mapping */
#define GPIO_AF_SDIO ((uint8_t)0xC) /* SDIO Alternate Function mapping */
/**
* @brief AF 13 selection
*/
#define GPIO_AF_DCMI ((uint8_t)0x0D) /* DCMI Alternate Function mapping */
/**
* @brief AF 14 selection
*/
#define GPIO_AF_LTDC ((uint8_t)0x0E) /* LCD-TFT Alternate Function mapping */
/**
* @brief AF 15 selection
*/
#define GPIO_AF_EVENTOUT ((uint8_t)0x0F) /* EVENTOUT Alternate Function mapping */
2015-11-19 04:32 AM
hi clive,
I am learning new so I wonder, why use alternative function and when alternative function.2015-11-19 05:35 AM
I am learning new so I wonder, why use alternative function and when alternative function.
There are more peripherals with inputs and outputs than there are pins on the device. The ability to multiplex (mux) them to different pins provides some degree of flexibility in the peripherals and devices used. Routing every function to every pin would require a ridiculous amount of silicon, so the the choices are limited, you might have to juggle things to get the set of functionality you want. It's not possible to use all peripherals at once, it's a general purpose device, and most people only need a subset for their designs.When using external memory buses, and LCD, these soak up a lot of pins, and often require much higher pin count devices.2015-11-19 06:29 AM
2015-11-19 07:39 AM
so I mean, using LCD pins can use any purpose at the same time, am I right??
I'm not sure why this is so complicated. NO, you have multiple choices, but you only get to pick ONE function. Think of it like a Volume Knob with specific, discrete settings, 0..152015-11-20 06:43 AM