LTC294X.h

00001 #ifndef LTC294X_H
00002 #define LTC294X_H
00003 
00004 #include "mbed.h"
00005 
00006 #define LTC_CONSOLE_OUTOUT 1 /* Set this if you need debug messages on the console;    */
00007                             /* it will have an impact on code-size and power consumption. */
00008 
00009 #if LTC_CONSOLE_OUTOUT
00010 //Serial usb(USBTX, USBRX); // tx, rx
00011 extern Serial  pc;
00012 #define DEBUG(...) { pc.printf(__VA_ARGS__); }
00013 #else
00014 #define DEBUG(...) /* nothing */
00015 #endif /* #if NEED_CONSOLE_OUTPUT */
00016 
00017 //gets a bit position by shifting 1
00018 #define _BV(x) (1 << x)
00019 
00020 // sbi sets a particular bit and cbi clears the bit (target byte-word, bit position)
00021 #define sbi(y,x); y|=_BV(x)
00022 #define cbi(y,x); y&=~_BV(x)
00023 
00024 
00025 //BIT 7-6 ADC MODE SELECTOR
00026 #define ADC_AUTO    0x00
00027 #define ADC_VOLT    0x01
00028 #define ADC_TEMP    0x02
00029 #define ADC_SLEEP   0x03
00030 
00031 //BIT 2-1 AL/CC MODE SELECTOR
00032 #define ALCC_ALERT  0x04
00033 #define ALCC_CCOMP  0x05
00034 #define ALCC_OFF    0x06
00035 
00036 //STATUS REGISTER.. READ BIT VALUES ONLY
00037 #define CHIP_ID             _BV(7)
00038 #define RESERVE             _BV(6)
00039 #define CHARGE_OVUV_ALERT   _BV(5)
00040 #define TEMPERATURE_ALERT   _BV(4)
00041 #define CHARGE_HIGH_ALERT   _BV(3)
00042 #define CHARGE_LOW_ALERT    _BV(2)
00043 #define VOLT_ALERT          _BV(1)
00044 #define UVLO_ALERT          _BV(0)
00045 
00046 
00047 //prescaler options
00048 #define PRESCALE_128               7
00049 #define PRESCALE_64                6
00050 #define PRESCALE_32                5
00051 #define PRESCALE_16                4
00052 #define PRESCALE_8                 3
00053 #define PRESCALE_4                 2
00054 #define PRESCALE_2                 1
00055 #define PRESCALE_1                 0
00056 
00057 //CONTROL REGISTER.. BIT LOCATIONS
00058 #define ADC_VOLT_MODE       7
00059 #define ADC_TEMP_MODE       6
00060 #define PRESCALER_2         5
00061 #define PRESCALER_1         4
00062 #define PRESCALER_0         3
00063 #define ALCC_ALERT_MODE     2
00064 #define ALCC_CHRGC_MODE     1
00065 #define IC_SHUTDOWN         0
00066 
00067 //I2C REGISTER ADDRESSES
00068 #define REG_STATUS          0x00    //  00h A Status R See Below
00069 #define REG_CONTROL         0x01    //  01h B Control R/W 3Ch
00070 #define ACC_MSB             0x02    //  02h C Accumulated Charge MSB R/W 7Fh
00071 #define ACC_LSB             0x03    //  03h D Accumulated Charge LSB R/W FFh
00072 #define CHRG_THH_MSB        0x04    //  04h E Charge Threshold High MSB R/W FFh
00073 #define CHRG_THH_LSB        0x05    //  05h F Charge Threshold High LSB R/W FFh
00074 #define CHRG_THL_MSB        0x06    //  06h G Charge Threshold Low MSB R/W 00h
00075 #define CHRG_THL_LSB        0x07    //  07h H Charge Threshold Low LSB R/W 00h
00076 #define VOLT_MSB            0x08    //  08h I Voltage MSB R XXh
00077 #define VOLT_LSB            0x09    //  09h J Voltage LSB R XXh
00078 #define VOLT_THH            0x0A    //  0Ah K Voltage Threshold High R/W FFh
00079 #define VOLT_THL            0x0B    //  0Bh L Voltage Threshold Low R/W 00h
00080 #define TEMP_MSB            0x0C    //  0Ch M Temperature MSB R XXh
00081 #define TEMP_LSB            0x0D    //  0Dh N Temperature LSB R XXh
00082 #define TEMPERATURE_THH     0x0E    //  0Eh O Temperature Threshold High R/W FFh
00083 #define TEMPERATURE_THL     0x0F    //  0Fh P Temperature Threshold Low R/W 00h
00084 
00085 
00086 /** LTC29421 class.
00087  *  interface LTC29421 coloumb counter on i2c port with interrupt, function name (and battery capacity in Ah Amp-hour).
00088  *
00089  * Example:
00090  * @code
00091  * #include "mbed.h"
00092  * #include "LTC29421.h"
00093  *
00094  * LTC29421 ltc(PTC9, PTC8, PTA4, &interrDOWN, 0.560);
00095  * 
00096  * int main() {
00097  *     float chLevel = ltc.accumulatedCharge();
00098  * }
00099  * @endcode
00100  */
00101  
00102 class LTC29421{
00103 public:
00104     /** create LTC29421 instance based on I2C, WARNING! use setPrescAndBattCap() to set Battery Capacity
00105      *
00106      * @param pin sda
00107      * @param pin scl
00108      * @param pin al/cc interrupt
00109      */
00110     LTC29421(PinName, PinName, PinName, void (*interruptFunc)(void));
00111 
00112     /** create LTC29421 instance based on I2C, 
00113      *  this will computer internal M prescale value and set internal max charge level
00114      *
00115      * @param pin sda
00116      * @param pin scl
00117      * @param pin al/cc interrupt
00118      * @param float battery capacity in Ah (Amp-hour)
00119      */
00120     LTC29421(PinName, PinName, PinName, void (*interruptFunc)(void), float);
00121     
00122 
00123     /** select an ADC measurement option for voltage / temperature
00124      *
00125      * @param ADC_x
00126      */
00127     void setADCMode(int);
00128 
00129     /** select a prescaler value (not required if object initialized with battery capacity 
00130      *
00131      * @param PRESCALE_x
00132      */
00133     void setPrescaler(int);
00134 
00135     /** returns prescale value in integer
00136      *
00137      * @returns int prescale value
00138      */
00139     int getPrescaler();
00140 
00141     /** configure the AL/CC interrupt: TODO works as Alarm only
00142      *
00143      * @param ALCC_x
00144      */
00145     void configALCC(int);
00146 
00147     /** shutsdown the analog section of LTC2942, also used to read accumulated charge registers
00148      *
00149      * @param none
00150      */
00151     void shutdown();
00152 
00153     /** wakes the analog section of LTC2942
00154      *
00155      * @param none
00156      */
00157     void wake();
00158 
00159     /** wakes the analog section of LTC2942
00160      *
00161      * @param none
00162      */
00163   
00164     /** amend the battery capacity, also computers prescaler M and adjusts internal Max battery capacity
00165      *
00166      * @param battery capacity in Ah (Amp-hour)
00167      */
00168     void setPrescAndBattCap(float);
00169 
00170     /** returns the 2 Byte accumulated charge register
00171      *
00172      * @return accumulated charge read as 2 byte hex value
00173      */
00174     int accumulatedChargeReg();
00175 
00176     /** write into the 2 Byte accumulated charge register
00177      *
00178      * @param accumulated charge write as 2 byte hex value
00179      */
00180     void accumulatedChargeReg(int);
00181 
00182     /** reads the accumulated charge register as a percent value computed from max battery capacity
00183      *
00184      * @return accumulated charge read as percent
00185      */
00186     float accumulatedCharge();
00187 
00188     /** writes the accumulated charge register as a percent value computed from max battery capacity
00189      *  use this to initialise the battery capacity if known, 
00190      *  or set it to 50% or set it to 100% if battery capacity reaches max
00191      * 
00192      *  @param accumulated charge as percent (0-100)
00193      */
00194     void accumulatedCharge(float);
00195 
00196     /** set low battery capacity threshhold
00197      *
00198      * @param float percent remaining value(0-100)
00199      */
00200     void setChargeThresholdLow(float);
00201 
00202     /** set high battery capacity threshhold
00203      *
00204      * @param float percent remaining value(0-100)
00205      */
00206     void setChargeThresholdHigh(float);    
00207     
00208     /** obtains battery voltage at (sense-) pin
00209      *  if required ADC is set 
00210      *
00211      * @return battery level in Volts
00212      */
00213     float voltage();
00214 
00215     /** set low battery level threshhold
00216      *
00217      * @param Voltage level in Volts
00218      */
00219     void setVoltageThresholdLow(float);
00220 
00221     /** set high battery level threshhold
00222      *
00223      * @param Voltage level in Volts
00224      */
00225     void setVoltageThresholdHigh(float);
00226     
00227     /** obtains IC temperature, if required ADC is set 
00228      *
00229      * @return temperature in centigrade
00230      */
00231     float temperature();
00232 
00233     /** set IC temperature low threshold
00234      *
00235      * @param temperauture in centigrade
00236      */
00237     void setTemperatureThresholdLow(float);
00238 
00239     /** set IC temperature high threshold
00240      *
00241      * @param temperauture in centigrade
00242      */
00243     void setTemperatureThresholdHigh(float);
00244     
00245 
00246     /** reads all LTC2942 register values prints on serial terminal
00247      *
00248      * @param none
00249      */
00250     void readAll();
00251 
00252     /** reads the status register first
00253      *  uses the ARA alert response protocol for SMBus to clear AL/CC pin
00254      *   
00255      *  int resp = ic.alertResponse();
00256      *      if((resp & TEMPERATURE_ALERT) == TEMPERATURE_ALERT) {   }
00257      *
00258      * @return STATUS register
00259      */
00260     int alertResponse();
00261 
00262 private:
00263     char getStatusReg();
00264     char getControlReg();
00265     void setControlReg(char);
00266 
00267     I2C _i2c;
00268     InterruptIn _alcc;
00269     
00270     char _addr;
00271     float _battCap;
00272     float _battMax;
00273     float _presc;
00274 };
00275 
00276 
00277 #endif