A library for ADS1015 and ADS1115 from Texas Instruments.
Dependents: IGGE_Power ADS1015-hello_world ADS1115-hello_world frdm_rtos_Eth ... more
Use like this
#include "mbed.h" #include "Adafruit_ADS1015.h" #include "USBSerial.h" #define SERIAL_BAUD_RATE 9600 I2C i2c(p23, p18); Adafruit_ADS1015 ads(&i2c); USBSerial pc; // USB CDC serial port int main() { uint16_t reading; while (1) { reading = ads.readADC_SingleEnded(0); // read channel 0 pc.printf("reading: %d\r\n", reading); // print reading wait(2); // loop 2 sek } }
Library ported from Arduino at github repository.
Breakout boards from Adafruit: http://learn.adafruit.com/adafruit-4-channel-adc-breakouts/overview
GitHub repository: https://github.com/adafruit/Adafruit_ADS1X15
Diff: Adafruit_ADS1015.cpp.orig
- Revision:
- 5:aa277517f0ad
- Parent:
- 4:6445a678d458
--- a/Adafruit_ADS1015.cpp.orig Sat Oct 11 08:44:20 2014 +0000 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,326 +0,0 @@ -/**************************************************************************/ -/*! - @file Adafruit_ADS1015.cpp - @author K.Townsend (Adafruit Industries) - @license BSD (see LICENSE.txt) - - Ported to mbed by Arve Seljebu - arve0.github.io - - Driver for the ADS1015/ADS1115 ADC - - This is a library for the Adafruit MPL115A2 breakout - ----> https://www.adafruit.com/products/1083 - - Adafruit invests time and resources providing this open source code, - please support Adafruit and open-source hardware by purchasing - products from Adafruit! - - @section HISTORY - - v1.0 - First release - v1.1.1 - Ported to mbed -*/ -/**************************************************************************/ - -#include <mbed.h> -#include "Adafruit_ADS1015.h" - -/**************************************************************************/ -/*! - @brief Writes 16-bits to the specified destination register -*/ -/**************************************************************************/ -void Adafruit_ADS1015::writeRegister(uint8_t i2cAddress, uint8_t reg, uint16_t value) -{ - char cmd[3]; - cmd[0] = (char)reg; - cmd[1] = (char)(value>>8); - cmd[2] = (char)(value & 0xFF); - m_i2c->write(i2cAddress, cmd, 3); -} - -/**************************************************************************/ -/*! - @brief Reads 16-bits from the specified register -*/ -/**************************************************************************/ -uint16_t Adafruit_ADS1015::readRegister(uint8_t i2cAddress, uint8_t reg) -{ - char data[2]; - data[0] = reg; // temporary use this to send address to conversion register - m_i2c->write(i2cAddress, data, 1); - m_i2c->read(i2cAddress, data, 2); - return (data[0] << 8 | data [1]); -} - -/**************************************************************************/ -/*! - @brief Instantiates a new ADS1015 class w/appropriate properties -*/ -/**************************************************************************/ -Adafruit_ADS1015::Adafruit_ADS1015(I2C* i2c, uint8_t i2cAddress) -{ - // shift 7 bit address 1 left: read expects 8 bit address, see I2C.h - m_i2cAddress = i2cAddress << 1; - m_conversionDelay = ADS1015_CONVERSIONDELAY; - m_bitShift = 4; - m_gain = GAIN_TWOTHIRDS; /* +/- 6.144V range (limited to VDD +0.3V max!) */ - m_i2c = i2c; -} - -/**************************************************************************/ -/*! - @brief Instantiates a new ADS1115 class w/appropriate properties -*/ -/**************************************************************************/ -Adafruit_ADS1115::Adafruit_ADS1115(I2C* i2c, uint8_t i2cAddress) -{ - // shift 7 bit address 1 left: read expects 8 bit address, see mbed's I2C.h - m_i2cAddress = i2cAddress << 1; - m_conversionDelay = ADS1115_CONVERSIONDELAY; - m_bitShift = 0; - m_gain = GAIN_TWOTHIRDS; /* +/- 6.144V range (limited to VDD +0.3V max!) */ - m_i2c = i2c; -} - -/**************************************************************************/ -/*! - @brief Sets the gain and input voltage range -*/ -/**************************************************************************/ -void Adafruit_ADS1015::setGain(adsGain_t gain) -{ - m_gain = gain; -} - -/**************************************************************************/ -/*! - @brief Gets a gain and input voltage range -*/ -/**************************************************************************/ -adsGain_t Adafruit_ADS1015::getGain() -{ - return m_gain; -} - -/**************************************************************************/ -/*! - @brief Gets a single-ended ADC reading from the specified channel -*/ -/**************************************************************************/ -uint16_t Adafruit_ADS1015::readADC_SingleEnded(uint8_t channel) -{ - if (channel > 3) { - return 0; - } - - // Start with default values - uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val) - ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val) - ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val) - ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val) - ADS1015_REG_CONFIG_DR_1600SPS | // 1600 samples per second (default) - ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default) - - // Set PGA/voltage range - config |= m_gain; - - // Set single-ended input channel - switch (channel) { - case (0): - config |= ADS1015_REG_CONFIG_MUX_SINGLE_0; - break; - case (1): - config |= ADS1015_REG_CONFIG_MUX_SINGLE_1; - break; - case (2): - config |= ADS1015_REG_CONFIG_MUX_SINGLE_2; - break; - case (3): - config |= ADS1015_REG_CONFIG_MUX_SINGLE_3; - break; - } - - // Set 'start single-conversion' bit - config |= ADS1015_REG_CONFIG_OS_SINGLE; - - // Write config register to the ADC - writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config); - - // Wait for the conversion to complete - wait_ms(m_conversionDelay); - - // Read the conversion results - // Shift 12-bit results right 4 bits for the ADS1015 - return readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift; -} - -/**************************************************************************/ -/*! - @brief Reads the conversion results, measuring the voltage - difference between the P (AIN0) and N (AIN1) input. Generates - a signed value since the difference can be either - positive or negative. -*/ -/**************************************************************************/ -int16_t Adafruit_ADS1015::readADC_Differential_0_1() -{ - // Start with default values - uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val) - ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val) - ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val) - ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val) - ADS1015_REG_CONFIG_DR_1600SPS | // 1600 samples per second (default) - ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default) - - // Set PGA/voltage range - config |= m_gain; - - // Set channels - config |= ADS1015_REG_CONFIG_MUX_DIFF_0_1; // AIN0 = P, AIN1 = N - - // Set 'start single-conversion' bit - config |= ADS1015_REG_CONFIG_OS_SINGLE; - - // Write config register to the ADC - writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config); - - // Wait for the conversion to complete - wait_ms(m_conversionDelay); - - // Read the conversion results - uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift; - if (m_bitShift == 0) { - return (int16_t)res; - } else { - // Shift 12-bit results right 4 bits for the ADS1015, - // making sure we keep the sign bit intact - if (res > 0x07FF) { - // negative number - extend the sign to 16th bit - res |= 0xF000; - } - return (int16_t)res; - } -} - -/**************************************************************************/ -/*! - @brief Reads the conversion results, measuring the voltage - difference between the P (AIN2) and N (AIN3) input. Generates - a signed value since the difference can be either - positive or negative. -*/ -/**************************************************************************/ -int16_t Adafruit_ADS1015::readADC_Differential_2_3() -{ - // Start with default values - uint16_t config = ADS1015_REG_CONFIG_CQUE_NONE | // Disable the comparator (default val) - ADS1015_REG_CONFIG_CLAT_NONLAT | // Non-latching (default val) - ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val) - ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val) - ADS1015_REG_CONFIG_DR_1600SPS | // 1600 samples per second (default) - ADS1015_REG_CONFIG_MODE_SINGLE; // Single-shot mode (default) - - // Set PGA/voltage range - config |= m_gain; - - // Set channels - config |= ADS1015_REG_CONFIG_MUX_DIFF_2_3; // AIN2 = P, AIN3 = N - - // Set 'start single-conversion' bit - config |= ADS1015_REG_CONFIG_OS_SINGLE; - - // Write config register to the ADC - writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config); - - // Wait for the conversion to complete - wait_ms(m_conversionDelay); - - // Read the conversion results - uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift; - if (m_bitShift == 0) { - return (int16_t)res; - } else { - // Shift 12-bit results right 4 bits for the ADS1015, - // making sure we keep the sign bit intact - if (res > 0x07FF) { - // negative number - extend the sign to 16th bit - res |= 0xF000; - } - return (int16_t)res; - } -} - -/**************************************************************************/ -/*! - @brief Sets up the comparator to operate in basic mode, causing the - ALERT/RDY pin to assert (go from high to low) when the ADC - value exceeds the specified threshold. - - This will also set the ADC in continuous conversion mode. -*/ -/**************************************************************************/ -void Adafruit_ADS1015::startComparator_SingleEnded(uint8_t channel, int16_t threshold) -{ - // Start with default values - uint16_t config = ADS1015_REG_CONFIG_CQUE_1CONV | // Comparator enabled and asserts on 1 match - ADS1015_REG_CONFIG_CLAT_LATCH | // Latching mode - ADS1015_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low (default val) - ADS1015_REG_CONFIG_CMODE_TRAD | // Traditional comparator (default val) - ADS1015_REG_CONFIG_DR_1600SPS | // 1600 samples per second (default) - ADS1015_REG_CONFIG_MODE_CONTIN | // Continuous conversion mode - ADS1015_REG_CONFIG_MODE_CONTIN; // Continuous conversion mode - - // Set PGA/voltage range - config |= m_gain; - - // Set single-ended input channel - switch (channel) { - case (0): - config |= ADS1015_REG_CONFIG_MUX_SINGLE_0; - break; - case (1): - config |= ADS1015_REG_CONFIG_MUX_SINGLE_1; - break; - case (2): - config |= ADS1015_REG_CONFIG_MUX_SINGLE_2; - break; - case (3): - config |= ADS1015_REG_CONFIG_MUX_SINGLE_3; - break; - } - - // Set the high threshold register - // Shift 12-bit results left 4 bits for the ADS1015 - writeRegister(m_i2cAddress, ADS1015_REG_POINTER_HITHRESH, threshold << m_bitShift); - - // Write config register to the ADC - writeRegister(m_i2cAddress, ADS1015_REG_POINTER_CONFIG, config); -} - -/**************************************************************************/ -/*! - @brief In order to clear the comparator, we need to read the - conversion results. This function reads the last conversion - results without changing the config value. -*/ -/**************************************************************************/ -int16_t Adafruit_ADS1015::getLastConversionResults() -{ - // Wait for the conversion to complete - wait_ms(m_conversionDelay); - - // Read the conversion results - uint16_t res = readRegister(m_i2cAddress, ADS1015_REG_POINTER_CONVERT) >> m_bitShift; - if (m_bitShift == 0) { - return (int16_t)res; - } else { - // Shift 12-bit results right 4 bits for the ADS1015, - // making sure we keep the sign bit intact - if (res > 0x07FF) { - // negative number - extend the sign to 16th bit - res |= 0xF000; - } - return (int16_t)res; - } -} \ No newline at end of file