Si114x.h

00001 #ifndef SI114X_H
00002 #define SI114X_H
00003 
00004 
00005 #include "mbed.h"
00006 /*
00007  * Class to interface with Si114x sensors
00008  *
00009  * Currently only intended for Si1146. Should work also on the Si1145,
00010  * but the extra LED of the Si1147 is not supported. Everyone is welcome
00011  * to add this support and submit a pull request.
00012  *
00013  * Aditionally only synchronous mode is for now supported (no async I2C API is used
00014  * and the sensor is not placed in automatic measurement mode: Each request starts a new
00015  * measurement. Also for this and other issues: Everyone is welcome to submit
00016  * pull requests
00017  *
00018  * For now this is just returning raw values, no scaling is done by the library code
00019 */
00020 class Si114x {
00021     public:
00022     /* Constructor to create new Si114x instance
00023     *
00024     * @param sda SDA pin of the I2C interface
00025     * @param scl SCL pin of the I2C interface
00026     */
00027     Si114x(PinName sda, PinName scl);
00028     
00029     /* Get the measure visible light intensity
00030     *
00031     * @return unsigned short (uint16_t) representing visible light intensity
00032     */
00033     unsigned short getVisibleLight(void);
00034     
00035     /* Get the measure IR light intensity
00036     *
00037     * @return unsigned short (uint16_t) representing IR light intensity
00038     */
00039     unsigned short getIRLight(void);
00040     
00041     /* Get the measure UV intensity
00042     *
00043     * The retval is supposed to be 10 times the UV index. It will be modified
00044     * to return a float representing the UV index once it doesn't claim
00045     * the UV index is 50 outside. 
00046     *
00047     * @return unsigned short (uint16_t) representing UV intensity
00048     */
00049     unsigned short getUVIndex(void);
00050     
00051     /* Perform a proximity measurement
00052     *
00053     * This enabled LEDs (set using setPSLEDs) and performs a 
00054     * reflection measurement. It can be used to obtain (relative)
00055     * proximity, but also to measure for example heartbeat, as in 
00056     * the HelloWorld program.
00057     *
00058     * Currently the code does not substract ambient light (todo)
00059     *
00060     * @param pschannel channel to use for the measurement (1-2)
00061     * @return unsigned short (uint16_t) representing the reflection
00062     */
00063     unsigned short getProximity(char pschannel);
00064     
00065     /* Set the LEDs for a given proximity measurement
00066     *
00067     * The Si1146 has two channels to do measurements with and can control 2 LEDs.
00068     * This function is used to set which LEDs are used for which channel.
00069     * Multiple LEDs can be active at the same time. By default the
00070     * constructor sets LED1 to be active with channel 1 and LED2 to
00071     * be active with channel 2.
00072     *
00073     * @param pschannel channel to set active LEDs for (1-2)
00074     * @param ledmask LEDs to be active for the set channel (bit 0 is LED1, bit1 is LED2)
00075     */
00076     void setPSLEDs(char pschannel, char ledmask);
00077     
00078     /* Verify I2C communication can occur with the sensor
00079     *
00080     * @return true when the sensor is found
00081     */
00082     bool verifyConnection(void);
00083     
00084     protected:
00085     char read_byte(const char reg);
00086     unsigned short read_word(const char reg);
00087     void write_byte(const char reg, const char byte);
00088     void param_set(const char param, const char value);
00089     char param_query(const char param);
00090     void write_cmd(const char cmd);
00091     
00092     I2C i2c;
00093     
00094     bool continious;
00095     };
00096 
00097 #endif