ADS1015 Module

This module contains the Zerynth driver for Texas Instruments ADS101x precision Analog-to-Digital Converters with I2C interface (datasheet).

Example:

from texas.ads1015 import ADS1015

...

ads = ads1015.ADS1015(I2C0, addr = 0x49, clk=400000)

ads.set(ch = 4, pga = 1)
value1 = ads.get_raw_data()

ads.set(ch = 3, pga = 4)
value2 = ads.get_raw_data()

ADS1015 class

class ADS1015(i2cdrv, addr = 0x48, clk = 100000)

Creates an instance of the ADS1015 class. This class allows the control of all ADS1013, ADS1014, and ADS1015 devices.

Parameters:

• i2cdrv – I2C Bus used ‘(I2C0, ...)’
• addr – Slave address, default 0x48
• clk – Clock speed, default 100 kHz

set(os = 0, ch = 4, pga = 2, mode = 0, sps = 4, cmode = 0, cpol = 0, clat = 0, cque = 3)

Sets the device’s configuration register.

Parameters:

• os : sets the Operational Status od the device. It can only be written when in power-down state and has no effect when a conversion is ongoing, available values are:

  • 0 : No effect
  • 1 : Start a single conversion (when in power-down state)

• ch : (ADS1015 only) Configure the input multiplexer.

  ch	positive channel	negative channel
  0	AIN0	AIN1
  1	AIN0	AIN3
  2	AIN1	AIN3
  3	AIN2	AIN3
  4	AIN0	GND
  5	AIN1	GND
  6	AIN2	GND
  7	AIN3	GND

• pga : (ADS1014 and ADS1015 only) PGA Gain selection.

  pga	Gain	ADC full-scale range
  0	1/3	± 6.144 V
  1	1/2	± 4.096 V
  2	1	± 2.048 V
  3	2	± 1.024 V
  4	4	± 0.512 V
  5	8	± 0.256 V
  6	8	± 0.256 V
  7	8	± 0.256 V

• mode : sets the device operating mode. Available values are:

  • 0 : Continuous-conversion mode.
  • 1 : Single-shot mode or power-down state

• sps : Data rate setting.

  sps	Samples per second
  0	128
  1	250
  2	490
  3	920
  4	1600
  5	2400
  6	3300
  7	3300

• cmode : (ADS1014 and ADS1015 only) Comparator operating mode.

  • 0 : Traditional comparator.
  • 1 : Window comparator.

• cpol : (ADS1014 and ADS1015 only) Set the polarity of the ALERT/RDY pin.

  • 0 : Active low.
  • 1 : Active high.

• clat : (ADS1014 and ADS1015 only) Controls whether the ALERT/RDY pin latches.

  • 0 : Nonlatching comparator.
  • 1 : Latching comparator.

• cque : (ADS1014 and ADS1015 only) Comparator queue and disable.

  cque	effect
  0	Assert ALERT/RDY pin after one conversion exceeding the threshold
  1	Assert ALERT/RDY pin after two conversion exceeding the threshold
  2	Assert ALERT/RDY pin after four conversion exceeding the threshold
  3	Disable comparator and set ALERT/RDY pin to high-impedance

set_threshold(low, high)

Set the upper and lower threshold values used by the comparator. The comparator is implemented as a digital comparator; therefore, the valuese must be updated whenever the PGA settings are changed.

Available values for both low and high parameters are 12-bit signed intergers, from -2048 to 2047.

get_raw_data()

Return the conversion result as an 12-bit signed integer. A positive full-scale input produces an output of 2047, a negative full-scale input produces an output of -2048.