用hal库驱动3个ADS1115采集电压，并通过串口发送

首先，需要在STM32CubeMX中配置好串口和I2C外设，并使能对应的GPIO引脚。具体步骤如下：

1. 打开STM32CubeMX软件，选择对应的芯片型号。

2. 在Pinout & Configuration选项卡中，选择对应的引脚模式。对于USART串口，需要选择Alternate Function，对应的引脚根据具体的芯片不同而有所不同。对于I2C外设，需要选择I2C模式，对应的引脚为SDA和SCL。

3. 在Configuration选项卡中，使能对应的外设，例如USART和I2C。

4. 配置ADS1115的寄存器，使其工作在连续采样模式下，并设置采样速率、增益等参数。

5. 使用HAL库中的I2C和USART驱动函数，读取ADS1115的数据，并将数据通过串口发送。

下面是一份参考代码，仅供参考：

#include "main.h"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"

#define ADS1115_ADDR 0x90

I2C_HandleTypeDef hi2c1;
UART_HandleTypeDef huart2;

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART2_UART_Init(void);
static void MX_I2C1_Init(void);
void ADS1115_Init(uint8_t addr);
uint16_t ADS1115_Read(uint8_t addr, uint8_t channel);
void USART_SendString(char* str);

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_USART2_UART_Init();
  MX_I2C1_Init();

  ADS1115_Init(ADS1115_ADDR);

  char buf[32];

  while (1)
  {
    uint16_t val1 = ADS1115_Read(ADS1115_ADDR, 0);
    uint16_t val2 = ADS1115_Read(ADS1115_ADDR, 1);
    uint16_t val3 = ADS1115_Read(ADS1115_ADDR, 2);

    sprintf(buf, "%d %d %d\r\n", val1, val2, val3);
    USART_SendString(buf);

    HAL_Delay(1000);
  }
}

void ADS1115_Init(uint8_t addr)
{
  uint8_t config[3];

  config[0] = 0x01; // Pointer to Config register
  config[1] = 0xC5; // 250SPS, FSR=4.096V
  config[2] = 0x83; // Continuous conversion, AIN0

  HAL_I2C_Master_Transmit(&hi2c1, addr, config, 3, HAL_MAX_DELAY);
}

uint16_t ADS1115_Read(uint8_t addr, uint8_t channel)
{
  uint8_t config[3];

  switch (channel)
  {
    case 0:
      config[1] = 0x83; // Continuous conversion, AIN0
      break;
    case 1:
      config[1] = 0xD3; // Continuous conversion, AIN1
      break;
    case 2:
      config[1] = 0xE3; // Continuous conversion, AIN2
      break;
    case 3:
      config[1] = 0xF3; // Continuous conversion, AIN3
      break;
  }

  config[0] = 0x01; // Pointer to Config register
  config[2] = 0x83; // Continuous conversion, AIN0

  HAL_I2C_Master_Transmit(&hi2c1, addr, config, 3, HAL_MAX_DELAY);
  HAL_Delay(10);

  uint8_t data[2];
  HAL_I2C_Master_Receive(&hi2c1, addr, data, 2, HAL_MAX_DELAY);

  uint16_t result = (data[0] << 8) | data[1];
  return result;
}

void USART_SendString(char* str)
{
    HAL_UART_Transmit(&huart2, (uint8_t*) str, strlen(str), HAL_MAX_DELAY);
}

void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  __HAL_RCC_PWR_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI|RCC_OSCILLATORTYPE_LSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.LSIState = RCC_LSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
  {
    Error_Handler();
  }
}

static void MX_I2C1_Init(void)
{
  hi2c1.Instance = I2C1;
  hi2c1.Init.Timing = 0x2000090E;
  hi2c1.Init.OwnAddress1 = 0;
  hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c1.Init.OwnAddress2 = 0;
  hi2c1.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
  hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
  if (HAL_I2C_Init(&hi2c1) != HAL_OK)
  {
    Error_Handler();
  }
}

static void MX_USART2_UART_Init(void)
{
  huart2.Instance = USART2;
  huart2.Init.BaudRate = 115200;
  huart2.Init.WordLength = UART_WORDLENGTH_8B;
  huart2.Init.StopBits = UART_STOPBITS_1;
  huart2.Init.Parity = UART_PARITY_NONE;
  huart2.Init.Mode = UART_MODE_TX_RX;
  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart2.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart2) != HAL_OK)
  {
    Error_Handler();
  }
}

static void MX_GPIO_Init(void)
{
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();
}

void Error_Handler(void)
{
  __disable_irq();
  while (1)
  {
  }
}

这是一个简单的示例代码，实际应用中需要根据自己的具体需求进行修改和完善。