Mark Gottscho
A compilation of some hardware sensors and their shared programming interfaces.
Diff: INA219.h
- Revision:
- 0:8d34cc2ff388
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/INA219.h Sun Mar 16 01:48:59 2014 +0000
@@ -0,0 +1,251 @@
+/* INA219.h
+ * Tested with mbed board: FRDM-KL46Z
+ * Author: Mark Gottscho
+ * mgottscho@ucla.edu
+ */
+
+ #ifndef INA219_H
+ #define INA219_H
+
+ #include "mbed.h"
+ #include "I2CSensor.h"
+ #include "PeriodicSensor.h"
+
+ /**
+ * This class allows for easy control over a INA219 current/power sensing IC.
+ */
+class INA219 : public I2CSensor, public PeriodicSensor {
+ public:
+ /**
+ * @param sda the pin identifier for SDA I2C signal
+ * @param scl the pin identifier for SCL I2C signal
+ * @param i2c_addr the 8-bit I2C address for this device. Note that LSB is a don't care.
+ */
+ INA219(PinName sda, PinName scl, int i2c_addr);
+
+ /**
+ * Destroys this object
+ */
+ ~INA219();
+
+ /**
+ * Initializes the device to some nice state.
+ */
+ void selfInit();
+
+ /**
+ * Performs a software reset of the device.
+ */
+ void reset();
+
+ /**
+ * Sets the bus voltage range to either 16V or 32V.
+ * @param enable if true, sets the bus voltage range to 32V. Else, sets it to 16V.
+ */
+ void setBusVoltageRange32V(bool enable);
+
+ /**
+ * @returns true if the bus voltage range is set to 32V. if false, bus voltage range is 16V.
+ */
+ bool isBusVoltageRange32V();
+
+ /**
+ * Sets the PGA amplifier gain for shunt voltage measurement.
+ * @param gain the gain level to set. Allowed values: 1, 2, 4, 8. Default is 8. Any other values will have no effect.
+ */
+ void setShuntAmpGain(unsigned int gain);
+
+ /**
+ * Gets the PGA amplifier gain for shunt voltage measurement.
+ * @returns the gain level
+ */
+ unsigned int getShuntAmpGain();
+
+ /**
+ * Sets the resolution and sample averaging of the bus or shunt ADC.
+ * If resolution is set, sample averaging is disabled.
+ * If sample averaging is set, resolution setting is disabled.
+ * @param shunt if true, sets for shunt ADC. if false, sets for bus ADC.
+ * @param resolution if true, sets ADC resolution using the third parameter. if false, sets the ADC sample averaging
+ * using the third parameter.
+ * @param value if resolution is true, then this is the resolution in bits to use. Allowed values:
+ * 9, 10, 11, or 12 bits.
+ * If resolution is false, then this is the number of samples to average in each data sample. Allowed values:
+ * 2, 4, 8, 16, 32, 64, or 128 samples.
+ * Any other values will cause this method to have no effect. Default is 12-bit resolution mode.
+ */
+ void setADCResolutionAndAveraging(bool shunt, bool resolution, unsigned int value);
+
+ /**
+ * Gets the resolution or number of samples in an average of the bus or shunt ADC.
+ * @param shunt if true, gets for shunt ADC. if false, gets for bus ADC.
+ * @param resolution sets this to true if the return value represents resolution in bits. else, sets it to false if return
+ * value represents sample averaging in # samples.
+ */
+ unsigned int getADCResolutionAndAveraging(bool shunt, bool &resolution);
+
+ /**
+ * Sets the operating mode of the device. If all parameters are false, the device powers down.
+ * If shuntVoltage and busVoltage are false but continuous is true, the device remains on but
+ * the ADC is powered down.
+ * @param shuntVoltage if true, samples the shunt voltage.
+ * @param busVoltage if true, samples the bus voltage.
+ * @param continuous if true, samples continuously, otherwise only on triggered reads.
+ */
+ void setMode(bool shuntVoltage, bool busVoltage, bool continuous);
+
+ /**
+ * Gets the operating mode of the device. If all parameters are false, the device is powered down.
+ * If shuntVoltage and busVoltage are false but continuous is true, the device is on but
+ * the ADC is powered down.
+ * @param shuntVoltage sets true if shunt voltage is being measured.
+ * @param busVoltage sets true if bus voltage is being measured.
+ * @param continuous sets true if continuous readings are being done.
+ */
+ void getMode(bool &shuntVoltage, bool &busVoltage, bool &continuous);
+
+ /**
+ * Gets the shunt voltage across the current sensing resistor.
+ * @param sampleNow if true, queries the device for the sample and returns it. if false, gets the last queried value.
+ * The latter is preferred if this object is set up to sample using interrupts.
+ * @returns 16-bit integer representing the shunt voltage.
+ */
+ int16_t getShuntVoltage(bool sampleNow);
+
+ /**
+ * Gets the shunt voltage across the current sensing resistor.
+ * @param sampleNow if true, queries the device for the sample and returns it. if false, gets the last queried value.
+ * The latter is preferred if this object is set up to sample using interrupts.
+ * @returns the shunt voltage in Volts
+ */
+ float getShuntVoltageFloat(bool sampleNow);
+
+
+ /**
+ * Gets the bus voltage at the negative terminal of the current sensing resistor (V-).
+ * @param sampleNow if true, queries the device for the sample and returns it. if false, gets the last queried value.
+ * The latter is preferred if this object is set up to sample using interrupts.
+ * @returns 16-bit integer representing the bus voltage.
+ */
+ int16_t getBusVoltage(bool sampleNow);
+
+ /**
+ * Gets the bus voltage across the current sensing resistor.
+ * @param sampleNow if true, queries the device for the sample and returns it. if false, gets the last queried value.
+ * The latter is preferred if this object is set up to sample using interrupts.
+ * @returns the bus voltage in Volts
+ */
+ float getBusVoltageFloat(bool sampleNow);
+
+ /**
+ * Gets the power consumed by the load. Note that calling this method with sampleNow == true
+ * will also implicitly sample current as well, which can be retrieved with a call to
+ * getCurrent(false) after calling getPower(true).
+ * @param sampleNow if true, queries the device for the sample and returns it. if false, gets the last queried value.
+ * The latter is preferred if this object is set up to sample using interrupts.
+ * @returns 16-bit integer representing power consumption of the load.
+ */
+ int16_t getPower(bool sampleNow);
+
+ /**
+ * Gets the power consumed by the load. Note that calling this method with sampleNow == true
+ * will also implicitly sample current as well, which can be retrieved with a call to
+ * getCurrentFloat(false) after calling getPowerFloat(true).
+ * @param sampleNow if true, queries the device for the sample and returns it. if false, gets the last queried value.
+ * The latter is preferred if this object is set up to sample using interrupts.
+ * @returns the load power in Watts
+ */
+ float getPowerFloat(bool sampleNow);
+
+ /**
+ * Gets the current sunk by the load.
+ * @param sampleNow if true, queries the device for the sample and returns it. if false, gets the last queried value.
+ * The latter is preferred if this object is set up to sample using interrupts.
+ * @returns 16-bit integer representing current sunk by the load.
+ */
+ int16_t getCurrent(bool sampleNow);
+
+ /**
+ * Gets the current delivered to the load
+ * @param sampleNow if true, queries the device for the sample and returns it. if false, gets the last queried value.
+ * The latter is preferred if this object is set up to sample using interrupts.
+ * @returns the load current in Amperes
+ */
+ float getCurrentFloat(bool sampleNow);
+
+ /**
+ * Gets the calibration configuration setting for current range.
+ * @returns 16-bit unsigned integer representing calibration register value
+ */
+ uint16_t getCalibration();
+
+ private:
+ /**
+ * Interrupt service routine for fetching power data from the device.
+ */
+ virtual void __sample_data_ISR();
+
+ /**
+ * Sets the calibration register of the device so that current and power measurements can be made. NOTE: This is a custom method for my project.
+ */
+ void __calibrate();
+
+ /////////////////////// VARIABLES //////////////////////////
+ bool __bus_voltage_range_32V;
+ unsigned int __shunt_amp_gain;
+ unsigned int __shunt_resolution;
+ unsigned int __shunt_num_samples_in_average;
+ unsigned int __bus_resolution;
+ unsigned int __bus_num_samples_in_average;
+ bool __active;
+ bool __measure_shunt_voltage;
+ bool __measure_bus_voltage;
+ bool __continuous_measurements;
+
+ volatile int16_t __shunt_voltage;
+ volatile int16_t __bus_voltage;
+ volatile int16_t __power;
+ volatile int16_t __shunt_current;
+ volatile uint16_t __calibration;
+
+ float __current_div; //Amps/level
+ float __power_div; //Watts/level
+
+
+
+ /////////////////////// CONSTANTS //////////////////////////
+
+ //Device register addresses
+ const static uint8_t CONFIG = 0x00;
+ const static uint8_t SHUNT_VOLTAGE = 0x01;
+ const static uint8_t BUS_VOLTAGE = 0x02;
+ const static uint8_t POWER = 0x03;
+ const static uint8_t CURRENT = 0x04;
+ const static uint8_t CALIBRATION = 0x05;
+
+ //Register masks
+ const static uint16_t CONFIG_RST_MASK = 0x8000; //b1000 0000 0000 0000
+ const static uint16_t CONFIG_BRNG_MASK = 0x2000; //b0010 0000 0000 0000
+ const static uint16_t CONFIG_PG_MASK = 0x1800; //b0001 1000 0000 0000
+ const static uint16_t CONFIG_BADC_MASK = 0x0780; //b0000 0111 1000 0000
+ const static uint16_t CONFIG_SADC_MASK = 0x0078; //b0000 0000 0111 1000
+ const static uint16_t CONFIG_MODE_MASK = 0x0007; //b0000 0000 0000 0111
+
+ //No masks needed for SHUNT_VOLTAGE register
+
+ const static uint16_t BUS_VOLTAGE_BD_MASK = 0xFFF8; //b1111 1111 1111 1000
+ const static uint16_t BUS_VOLTAGE_CNVR_MASK = 0x0002; //b0000 0000 0000 0010
+ const static uint16_t BUS_VOLTAGE_OVF_MASK = 0x0001; //b0000 0000 0000 0001
+
+ //No masks needed for POWER register
+
+ const static uint16_t CURRENT_CSIGN_MASK = 0x8000; //b1000 0000 0000 0000
+ const static uint16_t CURRENT_CD_MASK = 0x7FFF; //b0111 1111 1111 1111
+
+ const static uint16_t CALIBRATION_FS_MASK = 0xFFFE; //b1111 1111 1111 1110
+
+ const static float SHUNT_VOLTAGE_DIV = 0.00001; //10uV / level
+ const static float BUS_VOLTAGE_DIV = 0.004; //4mV / level
+};
+
+#endif
\ No newline at end of file