Si1133.h

00001 /***************************************************************************//**
00002  * @file Si1133.h
00003  *******************************************************************************
00004  * @section License
00005  * <b>(C) Copyright 2017 Silicon Labs, http://www.silabs.com</b>
00006  *******************************************************************************
00007  *
00008  * SPDX-License-Identifier: Apache-2.0
00009  *
00010  * Licensed under the Apache License, Version 2.0 (the "License"); you may
00011  * not use this file except in compliance with the License.
00012  * You may obtain a copy of the License at
00013  *
00014  * http://www.apache.org/licenses/LICENSE-2.0
00015  *
00016  * Unless required by applicable law or agreed to in writing, software
00017  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00018  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00019  * See the License for the specific language governing permissions and
00020  * limitations under the License.
00021  *
00022  ******************************************************************************/
00023 
00024 #ifndef SI1133_H
00025 #define SI1133_H
00026 
00027 #include "mbed.h"
00028 
00029 /** Si1133 class.
00030  *  Used for taking Light level and UV index measurements.
00031  *
00032  * Example:
00033  * @code
00034  * #include "mbed.h"
00035  * #include "Si1133.h"
00036  *
00037  * //Create an Si1133 object
00038  * Si1133 sensor(PC4, PC5);
00039  *
00040  * int main()
00041  * {
00042  *     //Try to open the Si1133
00043  *     if (sensor.open()) {
00044  *         printf("Device detected!\n");
00045  *
00046  *         while (1) {
00047  *             //Print the current light level
00048  *             printf("Lux = %.3f\n", (float)sensor.get_light_level());
00049  *             //Print the current UV index
00050  *             printf("UV index = %.3f\n", (float)sensor.get_uv_index());
00051  *
00052  *             //Sleep for 0.5 seconds
00053  *             wait(0.5);
00054  *         }
00055  *     } else {
00056  *         error("Device not detected!\n");
00057  *     }
00058  * }
00059  * @endcode
00060  */
00061 class Si1133
00062 {
00063 public:
00064 
00065     /** Create an Si1133 object connected to the specified I2C pins with the specified I2C slave address
00066      *
00067      * @param sda The I2C data pin.
00068      * @param scl The I2C clock pin.
00069      * @param hz The I2C bus frequency (defaults to 400kHz).
00070      */
00071     Si1133(PinName sda, PinName scl, int hz = 400000);
00072 
00073     /**
00074     * Si1133 destructor
00075     */
00076     ~Si1133(void);
00077 
00078     /** Probe for the Si1133 and try to initialize the sensor
00079      *
00080      * @returns
00081      *   'true' if the device exists on the bus,
00082      *   'false' if the device doesn't exist on the bus.
00083      */
00084     bool open();
00085 
00086     /** Measure the current light level (in lux) on the Si1133
00087      *
00088      * @returns The current temperature measurement in Lux.
00089      */
00090     float get_light_level();
00091 
00092     /** Measure the current UV Index on the Si1133
00093      *
00094      * @returns The current UV index measurement.
00095      */
00096     float get_uv_index();
00097 
00098     /** Do a combined measurement and return both the light level and UV index
00099      *
00100      * @param[out] light_level Measured light level in Lux
00101      * @param[out] uv_index Measured UV index
00102      *
00103      * @returns true if measurement was successful
00104      */
00105     bool get_light_and_uv(float *light_level, float *uv_index);
00106 
00107 #ifdef MBED_OPERATORS
00108     /** A shorthand for get_light_level()
00109      *
00110      * @returns The current temperature measurement in Lux.
00111      */
00112     operator float();
00113 #endif
00114 
00115 private:
00116     /**
00117     * @name I2C Registers
00118     * @{
00119     */
00120     enum Register {
00121         REG_PART_ID     = 0x00,     /**< Part ID                                                            */
00122         REG_HW_ID       = 0x01,     /**< Hardware ID                                                        */
00123         REG_REV_ID      = 0x02,     /**< Hardware revision                                                  */
00124         REG_HOSTIN0     = 0x0A,     /**< Data for parameter table on PARAM_SET write to COMMAND register    */
00125         REG_COMMAND     = 0x0B,     /**< Initiated action in Sensor when specific codes written here        */
00126         REG_IRQ_ENABLE  = 0x0F,     /**< Interrupt enable                                                   */
00127         REG_RESPONSE1   = 0x10,     /**< Contains the readback value from a query or a set command          */
00128         REG_RESPONSE0   = 0x11,     /**< Chip state and error status                                        */
00129         REG_IRQ_STATUS  = 0x12,     /**< Interrupt status                                                   */
00130         REG_HOSTOUT0    = 0x13,     /**< Captured Sensor Data                                               */
00131         REG_HOSTOUT1    = 0x14,     /**< Captured Sensor Data                                               */
00132         REG_HOSTOUT2    = 0x15,     /**< Captured Sensor Data                                               */
00133         REG_HOSTOUT3    = 0x16,     /**< Captured Sensor Data                                               */
00134         REG_HOSTOUT4    = 0x17,     /**< Captured Sensor Data                                               */
00135         REG_HOSTOUT5    = 0x18,     /**< Captured Sensor Data                                               */
00136         REG_HOSTOUT6    = 0x19,     /**< Captured Sensor Data                                               */
00137         REG_HOSTOUT7    = 0x1A,     /**< Captured Sensor Data                                               */
00138         REG_HOSTOUT8    = 0x1B,     /**< Captured Sensor Data                                               */
00139         REG_HOSTOUT9    = 0x1C,     /**< Captured Sensor Data                                               */
00140         REG_HOSTOUT10   = 0x1D,     /**< Captured Sensor Data                                               */
00141         REG_HOSTOUT11   = 0x1E,     /**< Captured Sensor Data                                               */
00142         REG_HOSTOUT12   = 0x1F,     /**< Captured Sensor Data                                               */
00143         REG_HOSTOUT13   = 0x20,     /**< Captured Sensor Data                                               */
00144         REG_HOSTOUT14   = 0x21,     /**< Captured Sensor Data                                               */
00145         REG_HOSTOUT15   = 0x22,     /**< Captured Sensor Data                                               */
00146         REG_HOSTOUT16   = 0x23,     /**< Captured Sensor Data                                               */
00147         REG_HOSTOUT17   = 0x24,     /**< Captured Sensor Data                                               */
00148         REG_HOSTOUT18   = 0x25,     /**< Captured Sensor Data                                               */
00149         REG_HOSTOUT19   = 0x26,     /**< Captured Sensor Data                                               */
00150         REG_HOSTOUT20   = 0x27,     /**< Captured Sensor Data                                               */
00151         REG_HOSTOUT21   = 0x28,     /**< Captured Sensor Data                                               */
00152         REG_HOSTOUT22   = 0x29,     /**< Captured Sensor Data                                               */
00153         REG_HOSTOUT23   = 0x2A,     /**< Captured Sensor Data                                               */
00154         REG_HOSTOUT24   = 0x2B,     /**< Captured Sensor Data                                               */
00155         REG_HOSTOUT25   = 0x2C,     /**< Captured Sensor Data                                               */
00156     };
00157     /**@}*/
00158 
00159     /**
00160     * @name Parameters
00161     * @{
00162     */
00163     enum Parameter {
00164         PARAM_I2C_ADDR      = 0x00, /**< I2C address                                                        */
00165         PARAM_CH_LIST       = 0x01, /**< Channel list                                                       */
00166         PARAM_ADCCONFIG0    = 0x02, /**< ADC config for Channel 0                                           */
00167         PARAM_ADCSENS0      = 0x03, /**< ADC sensitivity setting for Channel 0                              */
00168         PARAM_ADCPOST0      = 0x04, /**< ADC resolution, shift and threshold settings for Channel 0         */
00169         PARAM_MEASCONFIG0   = 0x05, /**< ADC measurement counter selection for Channel 0                    */
00170         PARAM_ADCCONFIG1    = 0x06, /**< ADC config for Channel 1                                           */
00171         PARAM_ADCSENS1      = 0x07, /**< ADC sensitivity setting for Channel 1                              */
00172         PARAM_ADCPOST1      = 0x08, /**< ADC resolution, shift and threshold settings for Channel 1         */
00173         PARAM_MEASCONFIG1   = 0x09, /**< ADC measurement counter selection for Channel 1                    */
00174         PARAM_ADCCONFIG2    = 0x0A, /**< ADC config for Channel 2                                           */
00175         PARAM_ADCSENS2      = 0x0B, /**< ADC sensitivity setting for Channel 2                              */
00176         PARAM_ADCPOST2      = 0x0C, /**< ADC resolution, shift and threshold settings for Channel 2         */
00177         PARAM_MEASCONFIG2   = 0x0D, /**< ADC measurement counter selection for Channel 2                    */
00178         PARAM_ADCCONFIG3    = 0x0E, /**< ADC config for Channel 3                                           */
00179         PARAM_ADCSENS3      = 0x0F, /**< ADC sensitivity setting for Channel 3                              */
00180         PARAM_ADCPOST3      = 0x10, /**< ADC resolution, shift and threshold settings for Channel 3         */
00181         PARAM_MEASCONFIG3   = 0x11, /**< ADC measurement counter selection for Channel 3                    */
00182         PARAM_ADCCONFIG4    = 0x12, /**< ADC config for Channel 4                                           */
00183         PARAM_ADCSENS4      = 0x13, /**< ADC sensitivity setting for Channel 4                              */
00184         PARAM_ADCPOST4      = 0x14, /**< ADC resolution, shift and threshold settings for Channel 4         */
00185         PARAM_MEASCONFIG4   = 0x15, /**< ADC measurement counter selection for Channel 4                    */
00186         PARAM_ADCCONFIG5    = 0x16, /**< ADC config for Channel 5                                           */
00187         PARAM_ADCSENS5      = 0x17, /**< ADC sensitivity setting for Channel 5                              */
00188         PARAM_ADCPOST5      = 0x18, /**< ADC resolution, shift and threshold settings for Channel 5         */
00189         PARAM_MEASCONFIG5   = 0x19, /**< ADC measurement counter selection for Channel 5                    */
00190         PARAM_MEASRATE_H    = 0x1A, /**< Main measurement rate counter MSB                                  */
00191         PARAM_MEASRATE_L    = 0x1B, /**< Main measurement rate counter LSB                                  */
00192         PARAM_MEASCOUNT0    = 0x1C, /**< Measurement rate extension counter 0                               */
00193         PARAM_MEASCOUNT1    = 0x1D, /**< Measurement rate extension counter 1                               */
00194         PARAM_MEASCOUNT2    = 0x1E, /**< Measurement rate extension counter 2                               */
00195         PARAM_THRESHOLD0_H  = 0x25, /**< Threshold level 0 MSB                                              */
00196         PARAM_THRESHOLD0_L  = 0x26, /**< Threshold level 0 LSB                                              */
00197         PARAM_THRESHOLD1_H  = 0x27, /**< Threshold level 1 MSB                                              */
00198         PARAM_THRESHOLD1_L  = 0x28, /**< Threshold level 1 LSB                                              */
00199         PARAM_THRESHOLD2_H  = 0x29, /**< Threshold level 2 MSB                                              */
00200         PARAM_THRESHOLD2_L  = 0x2A, /**< Threshold level 2 LSB                                              */
00201         PARAM_BURST         = 0x2B, /**< Burst enable and burst count                                       */
00202     };
00203     /**@}*/
00204 
00205     /**
00206     * @name Commands
00207     * @{
00208     */
00209     enum Command {
00210         CMD_RESET_CMD_CTR   = 0x00, /**< Resets the command counter                                         */
00211         CMD_RESET           = 0x01, /**< Forces a Reset                                                     */
00212         CMD_NEW_ADDR        = 0x02, /**< Stores the new I2C address                                         */
00213         CMD_FORCE_CH        = 0x11, /**< Initiates a set of measurements specified in CHAN_LIST parameter   */
00214         CMD_PAUSE_CH        = 0x12, /**< Pauses autonomous measurements                                     */
00215         CMD_START           = 0x13, /**< Starts autonomous measurements                                     */
00216         CMD_PARAM_SET       = 0x80, /**< Sets a parameter                                                   */
00217         CMD_PARAM_QUERY     = 0x40, /**< Reads a parameter                                                  */
00218     };
00219     /**@}*/
00220 
00221     /**
00222     * @name Responses
00223     * @{
00224     */
00225     enum Response {
00226         RSP0_CHIPSTAT_MASK  = 0xE0, /**< Chip state mask in Response0 register                              */
00227         RSP0_COUNTER_MASK   = 0x1F, /**< Command counter and error indicator mask in Response0 register     */
00228         RSP0_SLEEP          = 0x20, /**< Sleep state indicator bit mask in Response0 register               */
00229     };
00230     /**@}*/
00231 
00232     /**
00233      * @brief
00234      *    Structure to store the data measured by the Si1133
00235      */
00236     typedef struct {
00237         uint8_t     irq_status;     /**< Interrupt status of the device    */
00238         int32_t     ch0;            /**< Channel 0 measurement data        */
00239         int32_t     ch1;            /**< Channel 1 measurement data        */
00240         int32_t     ch2;            /**< Channel 2 measurement data        */
00241         int32_t     ch3;            /**< Channel 3 measurement data        */
00242     } Samples_t;
00243 
00244     /**
00245      * @brief
00246      *    Structure to store the calculation coefficients
00247      */
00248     typedef struct {
00249         int16_t     info;           /**< Info                              */
00250         uint16_t    mag;            /**< Magnitude                         */
00251     } Coeff_t;
00252 
00253     /**
00254      * @brief
00255      *    Structure to store the coefficients used for Lux calculation
00256      */
00257     typedef struct {
00258         Coeff_t   coeff_high[4];   /**< High amplitude coeffs */
00259         Coeff_t   coeff_low[9];    /**< Low amplitude coeffs  */
00260     } LuxCoeff_t;
00261 
00262     /* Forward-declare constant coefficient table */
00263     static const LuxCoeff_t lk;
00264     static const Coeff_t uk[];
00265 
00266     /* Private functions */
00267     uint32_t read_register(enum Register reg, uint8_t *data);
00268     uint32_t write_register(enum Register reg, uint8_t data);
00269     uint32_t write_register_block(enum Register reg, uint8_t length, uint8_t *data);
00270     uint32_t read_register_block(enum Register reg, uint8_t length, uint8_t *data);
00271     uint32_t get_irq_status(uint8_t *irq_status);
00272     uint32_t wait_until_sleep(void);
00273     uint32_t reset(void);
00274     uint32_t reset_cmd_counter (void);
00275     uint32_t send_cmd(enum Command command);
00276     uint32_t force_measurement (void);
00277     uint32_t pause_measurement (void);
00278     uint32_t start_measurement (void);
00279     uint32_t set_parameter (enum Parameter address, uint8_t value);
00280     uint32_t read_parameter (enum Parameter address);
00281     uint32_t init (void);
00282     uint32_t deinit (void);
00283     uint32_t measure (Samples_t *samples);
00284     int32_t  get_uv (int32_t uv);
00285     int32_t  get_lux (int32_t vis_high, int32_t vis_low, int32_t ir);
00286     uint32_t measure_lux_uv (float *lux, float *uvi);
00287     uint32_t get_measurement (float *lux, float *uvi);
00288     uint32_t get_hardware_id (uint8_t *hardware_id);
00289 
00290     int32_t calculate_polynomial_helper (int32_t input, int8_t fraction, uint16_t mag, int8_t  shift);
00291     int32_t calculate_polynomial (int32_t x, int32_t y, uint8_t input_fraction, uint8_t output_fraction, uint8_t num_coeff, const Coeff_t *kp);
00292 
00293     /* Member variables */
00294     I2C m_I2C;
00295 };
00296 
00297 #endif