Revision 0:4287b7d9c9ca, committed 2018-07-01

Comitter:

daniel_davvid

Date:

Sun Jul 01 12:00:52 2018 +0000

Commit message:

No significant changes

Changed in this revision

diff -r 000000000000 -r 4287b7d9c9ca MAX17043.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MAX17043.cpp	Sun Jul 01 12:00:52 2018 +0000
@@ -0,0 +1,118 @@
+/* MAX17043.cpp
+ * Tested with mbed board: FRDM-KL46Z
+ * Author: Mark Gottscho
+ * mgottscho@ucla.edu
+ */
+
+
+#include "mbed.h"
+#include "MAX17043.h"
+#include <new>
+
+MAX17043::MAX17043(PinName sda, PinName scl, int i2c_addr) : i2c_(*reinterpret_cast<I2C*>(i2cRaw)), __i2c_addr(i2c_addr)
+{
+    // Placement new to avoid additional heap memory allocation.
+    new(i2cRaw) I2C(sda, scl);
+
+    selfInit();
+}
+
+MAX17043::MAX17043(I2C &i2c, int i2c_addr): i2c_(i2c), __i2c_addr(i2c_addr)
+{
+    selfInit();
+}
+
+MAX17043::~MAX17043() { }
+
+void MAX17043::selfInit()
+{
+    __soc = 0;
+    __vcell = 0;
+    reset();
+}
+
+void MAX17043::reset()
+{
+    uint16_t data = RST_CODE;
+    setRegister16b(COMMAND_MSB, data);
+    wait(0.130); //wait 130ms until first readings are valid (125ms est)
+}
+
+uint16_t MAX17043::getVersion()
+{
+    uint8_t data = getRegister(VERSION_MSB);
+    return (data << 8) | (getRegister(VERSION_LSB));
+}
+
+uint16_t MAX17043::getVCell()
+{
+    uint16_t data = getRegister16b(VCELL_MSB);
+    __vcell = data >> 4; //right shift by 4 to throw out the don't care bits
+    return __vcell;
+}
+
+float MAX17043::getFloatVCell()
+{
+    return getVCell() * DIV_VCELL;
+}
+
+uint16_t MAX17043::getSOC()
+{
+    uint8_t data = getRegister(SOC_MSB);
+    __soc =  (data << 8) | (getRegister(SOC_LSB));
+    return __soc;
+}
+
+float MAX17043::getFloatSOC()
+{
+    return getSOC() * DIV_SOC;
+}
+
+
+void MAX17043::setRegister16b(const uint8_t reg_addr, const uint16_t data)
+{
+    uint8_t dataMSB = (data >> 8) & 0x00FF;
+    uint8_t dataLSB = data & 0x00FF;
+    uint8_t payload[3] = {reg_addr, dataMSB, dataLSB};
+    __writeReg(payload, 3);
+}
+void MAX17043::setRegister(const uint8_t reg_addr, const uint8_t data)
+{
+    uint8_t payload[2] = {reg_addr, data};
+    __writeReg(payload, 2);
+}
+
+uint8_t MAX17043::getRegister(const uint8_t reg_addr)
+{
+    uint8_t data;
+    __readReg(reg_addr, &data, 1);
+    return data;
+}
+
+uint16_t MAX17043::getRegister16b(const uint8_t reg_addr)
+{
+    uint8_t payload[2];
+    __readReg(reg_addr, payload, 2);
+    uint16_t data = (payload[0] << 8) | (payload[1]);
+    return data;
+}
+int MAX17043::__readReg(const uint8_t reg_addr, uint8_t *data, int len)
+{
+    int retval = 0;
+
+    retval = i2c_.write(__i2c_addr, (char *) &reg_addr, 1, true);
+    if (retval != 0) {
+        return retval;
+    }
+    retval = i2c_.read(__i2c_addr, (char *) data, len);
+
+    return retval;
+}
+
+int MAX17043::__writeReg(const uint8_t *data, int total_len)
+{
+    int retval = 0;
+    retval = i2c_.write(__i2c_addr, (char *) data, total_len);
+
+    return retval;
+}

diff -r 000000000000 -r 4287b7d9c9ca MAX17043.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MAX17043.h	Sun Jul 01 12:00:52 2018 +0000
@@ -0,0 +1,113 @@
+/* MAX17043.h
+ * Tested with mbed board: FRDM-KL46Z
+ * Author: Mark Gottscho
+ * mgottscho@ucla.edu
+ */
+ 
+#ifndef MAX17043_H
+#define MAX17043_H
+
+#include "mbed.h"
+ 
+/**
+* This class allows for easy control over a MAX17043 LiPo fuel gauge IC.
+*/
+class MAX17043 {
+    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.
+         */
+        MAX17043(PinName sda, PinName scl, int i2c_addr=0x6c);
+        MAX17043(I2C &i2c, int i2c_addr=0x6c);
+        
+        /**
+         *
+         */
+        ~MAX17043();
+        
+        /**
+         * Initializes the device to some preferred state.
+         */
+        void selfInit();
+        
+        /**
+         * Performs a software reset of the device.
+         */
+        void reset();
+        
+        /**
+         * @returns the IC version code
+         */
+        uint16_t getVersion();
+        
+        /**
+         * @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 battery voltage raw ADC value
+         */
+        uint16_t getVCell();
+        
+        /**
+         * @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 battery voltage as floating point
+         */
+        float getFloatVCell();
+        
+        /**
+         * @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 battery state of charge as computed by the ModelGauge algorithm. High byte: units of %. Low byte: units of 1/256%.
+         */
+        uint16_t getSOC();
+        
+        /**
+         * @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 battery state of charge in %, as a floating point #
+         */
+        float getFloatSOC(); 
+        
+        uint8_t getRegister(const uint8_t reg_addr);
+        uint16_t getRegister16b(const uint8_t reg_addr);
+        void setRegister(const uint8_t reg_addr, const uint8_t data);
+        void setRegister16b(const uint8_t reg_addr, const uint16_t data);
+        int __writeReg(const uint8_t *data, int total_len);
+        int __readReg(const uint8_t reg_addr, uint8_t *data, int len);
+        
+    private:
+    
+        I2C &i2c_;
+        char i2cRaw[sizeof(I2C)];
+        
+        int __i2c_addr;
+        uint16_t __soc;
+        uint16_t __vcell;
+    
+        ///////////////// CONSTANTS /////////////////////
+        
+        //Device register addresses
+        static const uint8_t VCELL_MSB =            0x02; //Read only
+        static const uint8_t VCELL_LSB =            0x03; //Read only
+        static const uint8_t SOC_MSB =              0x04; //Read only
+        static const uint8_t SOC_LSB =              0x05; //Read only
+        static const uint8_t MODE_MSB =             0x06; //Write only
+        static const uint8_t MODE_LSB =             0x07; //Write only
+        static const uint8_t VERSION_MSB =          0x08; //Read only
+        static const uint8_t VERSION_LSB =          0x09; //Read only
+        static const uint8_t CONFIG_MSB =           0x0C; //Read/write
+        static const uint8_t CONFIG_LSB =           0x0D; //Read/write
+        static const uint8_t COMMAND_MSB =          0xFE; //Write only
+        static const uint8_t COMMAND_LSB =          0xFF; //Write only
+        
+        static const uint16_t RST_CODE =            0x5400; //reset code for COMMAND 16-bit register
+    
+        //Levels
+        static const float DIV_VCELL =              1.25e-3; //1.25 mV/level
+        static const float DIV_SOC =                0.00390625; //1/256% / level
+};
+
+ 
+ #endif
\ No newline at end of file