ESP32C3 I2C no ack无应答怎么解决？

（一）现象

我使用idf开发esp32c3，使用i2c外设时出现问题。I2C正常发送了出去，但从机没有应答。

我此前使用过nxp的lpc55s69进行过测试，并将这两次的波形使用逻辑分析仪采集出来，区别仅有ACK应答。读取数据的时候现象也是一样的，从机无法作出应答，但时序波形与lpc55s69下实验仅有ack部分有区别。

从机使用AS5600和ADXL345都测试过，现象如上一致。

引脚也更换过多个，包括4、5、6、8、9，都是如此。



实验使用的esp32c3为合宙版。后来又使用安可信的esp32（非c3），额外编写esp32工程，现象依然如此。

实验使用的idf为v4.4-release分支。开发环境ubuntu20.04+vscode+idf4.4

I use idf to program esp32c3, and problem occurred when using i2c. The i2c was send successfully as display in logic analyzer, but no ack receive from slaver.

I had been test the slaver(both adxl345 and as5600) in NXP's lpc55s69, and it work as same as above, except the ack is successfully receive.

I have change the pin of i2c, but it does not work!

the board in this experience is esp32c3 developed by hezhou:


the idf version is v4.4-release.

and I develop it in ubuntu20.04+vscode+idf4.4

（二）代码

      
初始化 init


static esp_err_t i2c_master_init(void)

{

    int i2c_master_port = I2C_MASTER_NUM;



    i2c_config_t conf = {

        .mode = I2C_MODE_MASTER,

        .sda_io_num = I2C_MASTER_SDA_IO,

        .scl_io_num = I2C_MASTER_SCL_IO,

        .sda_pullup_en = GPIO_PULLUP_ENABLE,

        .scl_pullup_en = GPIO_PULLUP_ENABLE,

        .master.clk_speed = I2C_MASTER_FREQ_HZ

    };



    i2c_param_config(i2c_master_port, &conf);



    return i2c_driver_install(i2c_master_port, conf.mode, I2C_MASTER_RX_BUF_DISABLE, I2C_MASTER_TX_BUF_DISABLE, 0);

}



逻辑代码 the logic code

1-自己编写cmd-program by cmd



        // i2c_cmd_handle_t cmd = i2c_cmd_link_create();

        // i2c_master_start(cmd);

        // i2c_master_write_byte(cmd, AS5600_I2C_ADDR << 1 | I2C_MASTER_WRITE, false);

        // i2c_master_write_byte(cmd, 0x00, false);

        // i2c_master_stop(cmd);

        // ret = i2c_master_cmd_begin(0, cmd, 1000 / portTICK_RATE_MS);

        // i2c_cmd_link_delete(cmd);



        // cmd = i2c_cmd_link_create();

        // vTaskDelay(50 / portTICK_PERIOD_MS);

        // i2c_master_start(cmd);

        // i2c_master_write_byte(cmd, AS5600_I2C_ADDR << 1 | I2C_MASTER_READ, false);

        // i2c_master_read_byte(cmd, data, false);

        // i2c_master_stop(cmd);

        // ret = i2c_master_cmd_begin(0, cmd, 1000 / portTICK_RATE_MS);

        // i2c_cmd_link_delete(cmd);



2-调用函数-program by usb the sdk function

        i2c_master_write_to_device(I2C_NUM_0, 0x1D, data, 1, 500 / portTICK_PERIOD_MS);

（三）





基于以上情况，我只能怀疑是不是sda电平在接收ack的时候被主机钳住总线了？

毕竟合宙的板子似乎外部没有接任何器件了，尽只有我挂的adxl345

而且安可信的esp32板子也是同样的情况，难道是有什么配置没有配好吗？

I think the sda might be limited by esp32c3, thus the slaver can't pull it down?