ADS1114: ALERT/RDY Pin for Continuous conversion mode?

Thank you for relying to my query.

So you mean, if I want to read the ADC values from the ADS in a continuous manner, I do not need to employ the ALERT/RDY pin?

I can just use Config Reg, Point to conversion register and then read continuously?

Thanks in advance!

Yaagyanika Gehlot

Joseph,

Thank you for explanation! I think for my application I'd have to use the ALERT/RDY pin.

Do I have to write the config register, hi-threshold and low-threshold register each time before I'm reading from conversion register even if the config register is not to be changed?

Thanks in advance!

Yaagyanika Gehlot

Joseph,

Somehow I'm still not being able to read from the ADS1114.

I'm using STM32F072RBT6 i2c1 as master. If it's okay and not too much trouble, can you please take a look at my code and tell me if I'm doing anything wrong?

unsigned char buffer_Config_Reg[3] = {0x01, 0x82, 0xF7};	//	Config Reg pointer, MSB of Config Reg, LSB of Config Reg
unsigned char buffer_Lo_Thresh_Reg[3] = {0x02, 0x00, 0x00};	//	Lo_Thresh pointer, MSB of Lo_Thresh Reg, LSB of Lo_Thresh Reg
unsigned char buffer_Hi_Thresh_Reg[3] = {0x03, 0xFF, 0xFF};	//	Hi_Thresh pointer, MSB of Hi_Thresh, LSB of Hi_Thresh Reg
unsigned char buffer_Conv_Reg[1] = {0x00};	

void Begin_Transmission (void)
	{	
		HAL_I2C_Master_Transmit(&hi2c1, 0x48<<1, buffer_Config_Reg, 3, 100);	// Write to Config Register with selected FSR
		HAL_I2C_Master_Transmit(&hi2c1, 0x48<<1, buffer_Lo_Thresh_Reg, 3, 100);	// Low Threshold Register for continuous conversion
		HAL_I2C_Master_Transmit(&hi2c1, 0x48<<1, buffer_Hi_Thresh_Reg, 3, 100);	// Access High Threshold Register for continuous conversion	
	}

double Read_Current_Sensor(void)
	{
		HAL_I2C_Master_Transmit(&hi2c1, 0x48<<1, buffer_Conv_Reg, 1, 100);	// Pointing to Conversion register
		HAL_I2C_Master_Receive(&hi2c1,0x48<<1,buffer_receieve,2,100);		// Recieve data from the sensor and store it in buffer[0] and buffer[1]
		rawADC = buffer_receieve[0]<<8 | buffer_receieve[1];			// Combine 2 8-bit into 1 16bit
		Curr_Sensor_ADC_Value = ((rawADC * FSR) / 32767); 		        // ((raw * FSR) / ADC Resolution) 
		return Curr_Sensor_ADC_Value;
	}

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_I2C1_Init();
  
  Begin_Transmission();
  Main_Current = Read_Current_Sensor();
		
	while(1)
	{
		if (HAL_GPIO_ReadPin (GPIOA, GPIO_PIN_3) == 1)  // GPIO PA3 is ALERT/RDY
		{
		         Main_Current = Read_Current_Sensor();
                }
	}
}

Thanks in advance!

Yaagyanika

Oh, I think I forgot to add: 

float FSR = 4.096; 

Thanks.

Yaagyanika.

Yaaganika,

I'm afraid that I'm not very proficient in coding. 

Instead of looking at code, it's far easier to use an oscilloscope and look at the I2C waveforms for SDA and SCL directly. You should be able to match the waveforms you see to the timing diagrams you can find in Figures 30 and 31 of the datasheet.

Once you get some scope shots (or something from a logic analyzer), post the images back here and we can try to debug them.

Joseph Wu