Bend labs ADS Sensor STM32 ST HAL/Cube MX Library

Features

• Polling mode
• Ready for multi-devices use

Features to be implemented in future

• Address management
• Interrupt mode
• Provide an example application with Nucleo F401
• Provide easier FreeRTOS compatibility

Example

With the CubeMX project (.ioc file) provided generating the code

A Nucleo F401RE is required.

The example shows the concurrent use of 3 devices and have been tested with one and two axis devices.

We assume that you:

• You redirected the printf function to write on an known output (USART1 for this kind of Nucleo)
• You enabled

1. Generate the CubeMX project
2. Redirect the printf function to write on the output you want (ITM, or UART)
3. Enable float printf by adding "-u _printf_float" in the Linker flags
4. Add the following code section in Src/freertos.c :

#include "i2c.h"
#include "ads_hal.h"
#include "ads.h"

#define USING_ONE_AXIS_SENSORS 1
#define USING_TWO_AXIS_SENSORS 0

#if USING_ONE_AXIS_SENSORS
    #define SENSOR_1_ADDRESS 0x08
#elif USING_TWO_AXIS_SENSORS
    #define SENSOR_1_ADDRESS 0x10
#endif

#if USING_ONE_AXIS_SENSORS
    #define SENSOR_2_ADDRESS 0x09
#elif USING_TWO_AXIS_SENSORS
    #define SENSOR_2_ADDRESS 0x11
#endif

#if USING_ONE_AXIS_SENSORS
    #define SENSOR_3_ADDRESS 0x0A
#elif USING_TWO_AXIS_SENSORS
    #define SENSOR_3_ADDRESS 0x12
#endif

char getChar();
void calibrate(ads_handler_t * h)
{
	char c;
	c = getChar();

	ads_calibrate(h, 0, 0);
  if (h->type == ADS_TWO_AXIS)
  {
    printf("Good. Now press a key when the sensor is straight from base but 90 degrees up from table (along Y axis)\n");

    c = getChar();

    ads_calibrate(h, ADS_CALIBRATE_PERP, 90);
  }
  printf("Good. Now press a key when the sensor is flat on table but bent at 90 degrees (along X axis)\n");
  c = getChar();

  ads_calibrate(h, 1, 90);

  printf("Calibration complete.\n");
}
char getChar()
{
	uint8_t buf[0];
    HAL_StatusTypeDef res1;

    do {
    	res1 = HAL_UART_Receive(&huart2, buf, 1, 0x0A);
		  if (ads_poll_data(&ads1))
		  {
			  printf("%.1f\n", ads1.data[0]);
		  }
    } while (res1 != HAL_OK);
    return buf[0];
}

5. Place the following code section in the StartDefaultTask generated by CubeMX:

	ads_handler_t ads1;
	ads_handler_t ads2;
	ads_handler_t ads3;

	bool getDataFlag = true;

	/* Let the HAL know which i2c handler is being used */
	ads_hal_set_i2c_handler(&hi2c1);

	/* Set parameters */
	memset(&ads1, 0, sizeof(ads_handler_t));
	ads1.comSize = ADS_TRANSFER_SIZE_ONE_AXIS;
	ads1.sps = ADS_100_HZ;
	ads1.i2c_address = SENSOR_1_ADDRESS;
	ads1.reset_pin = GPIO_PIN_0;
	ads1.reset_port = (void*) GPIOC;
	ads1.interrupt_mode = 0; //disable the interrupt mode

	memset(&ads2, 0, sizeof(ads_handler_t));
	ads2.comSize = ADS_TRANSFER_SIZE_ONE_AXIS;
	ads2.sps = ADS_100_HZ;
	ads2.i2c_address = SENSOR_2_ADDRESS;
	ads2.reset_pin = GPIO_PIN_1;
	ads2.reset_port = (void*) GPIOC;
	ads2.interrupt_mode = 0; //disable the interrupt mode

	memset(&ads3, 0, sizeof(ads_handler_t));
	ads3.comSize = ADS_TRANSFER_SIZE_ONE_AXIS;
	ads3.sps = ADS_100_HZ;
	ads3.i2c_address = SENSOR_3_ADDRESS;
	ads3.reset_pin = GPIO_PIN_2;
	ads3.reset_port = (void*) GPIOC;
	ads3.interrupt_mode = 0; //disable the interrupt mode

	ads_init(&ads1); /* Init */
	ads_init(&ads2); /* Init */
	ads_init(&ads3); /* Init */
	osDelay(150);

  /* Infinite loop */
  for(;;)
  {
	  if (getDataFlag)
	  {
		  if (ads_poll_data(&ads1))
		  {
			  printf("%.1f\n", ads1.data[0]);
		  }
		  if (ads_poll_data(&ads2))
		  {
			  printf("%.1f\n", ads2.data[0]);
		  }
		  if (ads_poll_data(&ads3))
		  {
			  printf("%.1f\n", ads3.data[0]);
		  }
	  }
    osDelay(100);

    // Quick way to get an input from the user to see if we need to calibrate or enable/disable the stream
    memset(tbuf, 0, 16);
    HAL_StatusTypeDef res1;
    res1 = HAL_UART_Receive(&huart2, tbuf, 1, 0x0A);
    if (res1 == HAL_OK)
    {
    	printf("Input: %c\n", tbuf[0]);
    	if (tbuf[0] == 'a')
    	{
    		ads_calibrate(&ads1, ADS_CALIBRATE_FIRST, 0);
    		ads_calibrate(&ads2, ADS_CALIBRATE_FIRST, 0);
    	}
    	else if (tbuf[0] == 'b')
    	{
    		ads_calibrate(&ads1, ADS_CALIBRATE_FLAT, 90);
    		ads_calibrate(&ads2, ADS_CALIBRATE_FLAT, 90);
    	}
    	else if (tbuf[0] == 'c')
    	{
    		calibrate(&ads1);
    	}
    	else if (tbuf[0] == 'd')
    	{
    		getDataFlag = 1;
    	}
    	else if (tbuf[0] == 'e')
    	{
    		getDataFlag = 0;
    	}
    }
  }
}