Lack of signals Issue in I2C communication on the STM32G0B1RBT6

[5566]

我现在使用STM32G0B1RBT6的62 63管脚，需要使用他们I2C通讯功能。现在断开这两个端口一切外设，只留下2.2K上拉电阻。为啥示波器上面一直都没有信号，一直都是保持3.3V上拉。但是把这2个端口配置成普通的GPIO又能够电平翻转。

配置成I2C1 发数据，引脚上 测不到时钟信号。

Translation:

I am currently using pins 62 and 63 on the STM32G0B1RBT6 for I2C communication. I have disconnected all external peripherals from these pins, leaving only 2.2kΩ pull-up resistors in place. However, the oscilloscope shows no signal—the line remains held at the 3.3V pull-up level. Interestingly, if I reconfigure these pins as standard GPIOs, I am able to toggle their logic levels.

When I configure them for I2C1 and attempt to transmit data, no clock signal can be detected on the pin.

[mƎALLEm]

Hello ​@5566 and welcome to the ST community,

First, please use English in this community. You should read this when you start a new thread:

Second, you need also to provide more details about the board you are using and share your code and your schematics so other can help you efficiently.

Please read How to write your question to maximize your chances to find a solution.

Thank you for your understanding.

PS: I’ve already translated your request.

[Karl Yamashita]

You need to show some code you used to write/read to the I2C device. Assuming you are using HAL, you also need to check the HAL return status as that will tell you if it was successful or there was some error.

[5566]

Attached are the schematic, layout, and my code. We have now disconnected pins 62 and 63, leaving only the pull-up resistors R6 and R7 in place.  no signals can be measured. We have successfully brought up the UART and RS485 interfaces.

[TDK]

The code you attached doesn’t initialize or use I2C1 at all. It uses a software-based I2C. Since you said toggling is working when they are initialized as GPIO, it’s unclear why this code is shown.

[5566]

We configured the pins for software I2C and as regular GPIOs just to verify that the hardware of these pins is intact. Below is our I2C code. The signal stays constantly high on the oscilloscope, showing a flat 3.3 V line.

[EXUE.2]

Hi,  did you enable the I2C clock? I did not see it in your code.

[5566]

It is inside the zip file I sent you, as shown in the figure.
 

 

[EXUE.2]

I saw it, thanks. since the GPIO function is OK, generally, the greatest possibility is the configurations are not downloaded to its registers, so it is better to check I2C registers value after you run it step by step.

[Saket_Om]

Hello ​@5566 

What is the content of SR register after returning from HAL_I2C_IsDeviceReady.