Toggle SDA Pin on STM32F767ZI

[workingStudent]

Hi there,

I use a stm32 f767zi nucleo board in corporation with a security chip from microchip technology (atecc508a). To send a wake condition over i2c communication I have to set the sda pin for a certain amount of time "low". Is there any function to achieve this?

I've already tried to toggle the SDA Pin with "HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_9)", with no results but as I was told, this isn't working at all, because the pin was already configured.

I've configured my board with STM32CubeMX. PB8 and PB9 is for SCL and SDA of i2c connection.

I would appreciate any help.

Thank you very much.

[waclawek.jan]

Change the pin mode from AF to Out in GPIOx_MODER, perform the toggle using whatever means, and then change it back to AF.

I don't use Cube so don't know if there are any magic incantations to achieve this, but I doubt it.

JW

[BNara.1]

Hi did you find a way to way to send a wake command ? I tried using the HAL_I2C_Master_Transmit function for sending 0x00 to the I2C address, but no luck :(

Kindly share if you have found a way.

Thanks! @workingStudent​