STM32C071FBP6 Pin muxing issue

[Sumanth_Veeyes]

I am using STM32C071FBP6N MCU TSSOP 20 pin package for one of our project.
I am observing Pin_20 is muxed with lot of other pins like PB3/PB4/PB5/PB6. if i select PB3 as GPIO_Output using STM32CubeMx and generated a code. If i try to toggle the pin but its not working at all, none of the peripheral on that pin for PB3 is working. But if i select PB6 as GPIO_Output i can able to toggle or modify.
This issue is not only with Pin_20, same with Pin_1 also which shares with PB7/PB8, only PB7 is working.

I have tried with multiple chips what could be wrong in this scenario??

[Ghofrane GSOURI]

Hello @Sumanth_Veeyes 

Could you please provide your IOC in order to check your configuration and code .

I will be waiting for your feedback.

THX

Ghofrane

[Sumanth_Veeyes]

Here is the IOC generated using CubeMx for your reference

[TDK]

CubeMX assumes SECURE_MUXING_EN = 0 when it generates code, which is not the default.

Solved: STM32C092FCP6 SPI, SCK Pin remapping by CubeMX - STMicroelectronics Community

 

You can only use one muxed pin at a time if SECURE_MUXING_EN is enabled. Probably the settings in SYSCFG_CFGR3 are not being set up correctly by CubeMX. PB3 and PB7 are enabled by default which explains why they are working.

 

[Sumanth_Veeyes]

Without using CubeMX how can i hardcode SYS_CFG3 to use PB3??

[Ghofrane GSOURI]

Hello @Sumanth_Veeyes 

By checking the Firmware , you need to call the following HAL function 

 * @brief Set Pin Binding
 * @param pin_binding specifies which pin will bind a specific GPIO
 * for each die package
 * This parameter can be a value of @ref HAL_BIND_CFG
 * @retval None
 */
void HAL_SYSCFG_SetPinBinding(uint32_t pin_binding)
{
 /* Check the parameter */
 assert_param(IS_HAL_SYSCFG_PINBINDING(pin_binding));
 LL_SYSCFG_ConfigPinMux(pin_binding);
}

in your case : the parameter will be 

#define HAL_BIND_TSSOP20_PIN20_PB3 LL_PINMUX_TSSOP20_PIN20_PB3 /*!< STM32C071 TSSOP20 package, Pin20 assigned to GPIO PB3 */

So add this call in your code 

uint32_t pin_binding = HAL_BIND_TSSOP20_PIN20_PB3;
HAL_SYSCFG_SetPinBinding(pin_binding );

I will be waiting for your feedback.

THX

Ghofrane