File content as of revision 9:31d4e955ee92:

/**
 * @author Guillermo A Torijano
 * 
 * @section LICENSE
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @section DESCRIPTION
 *
 * Parallax SI1143 Gesture Sensor.
 *
 * Datasheet:
 *
 * http://www.silabs.com/Support%20Documents/TechnicalDocs/Si114x.pdf
 */

#include "SI1143.h"

SI1143::SI1143(PinName sda, PinName scl)
{
    wait_ms(30);
    i2c_ = new I2C(sda, scl);
    // 3.4MHz, as specified by the datasheet, but DO NOT USE.
    //i2c_->frequency(3400000);
    
    restart();
}

void SI1143::restart()
{
    command(RESET);
    wait_ms(30);
    
    //Do this because you have to
    write_reg(HW_KEY,HW_KEY_VAL0);
    
    // Setting up LED Power to FULL JUICE
    write_reg(PS_LED21,0x0F); // Was 0x0A
    write_reg(PS_LED3,0x00);
    //write_reg(PS_LED21,0xAA);
    //write_reg(PS_LED3,0x0A);
    
    //Activate ALS_IR, ALS_VIS, and PS1
    write_reg(PARAM_WR, ALS_IR_TASK + ALS_VIS_TASK + PS1_TASK);
    //write_reg(PARAM_WR, ALS_IR_TASK + ALS_VIS_TASK + PS1_TASK + PS2_TASK + PS3_TASK);
    command(PARAM_SET + (CHLIST & 0x1F));
    
    /*
    // Set PS_RANGE to high signal range
    write_reg(PARAM_WR, 0x04); // 0x24 for high signal, 0x04 for normal
    command(PARAM_SET + (PS_ADC_MISC & 0x1F));
    */
    //Set PS_ADC_COUNTER to lower time between ADC samples
    write_reg(PARAM_WR, 0x00);
    command(PARAM_SET + (PS_ADC_COUNTER & 0x1F));
    
    //Turn up the juice on PS ACD GAIN!
    write_reg(PARAM_WR, 0x00);
    command(PARAM_SET + (PS_ADC_GAIN & 0x1F));
    
    
    write_reg(INT_CFG,0x01); // Configure Interrupts 
    write_reg(IRQ_ENABLE,0x04); // Enable PS1
    write_reg(IRQ_MODE1,0);
    write_reg(IRQ_MODE2,0);
    
    write_reg(MEAS_RATE,0x94); //0x84 - wakes up every 10 ms
    write_reg(PS_RATE,0x08); //0x84 - wakes up every time measurement clock wakes up
    
    //write_reg(PS_ADC_MISC,0x24);
    //write_reg(PS1_ADCMUX,0x03);
}

void SI1143::command(char cmd)
{
    int val;
    
    val = read_reg(RESPONSE,1);
    while(val!=0)
    {
        write_reg(COMMAND,NOP);
        val = read_reg(RESPONSE,1);
    }
    do{
        write_reg(COMMAND,cmd);
        if(cmd==RESET) break;
        val = read_reg(RESPONSE,1);
    }while(val==0);
}

char SI1143::read_reg(/*unsigned*/ char address, int num_data) // Read a register
{
    char tx[1];
    char rx[1];
    
    //i2c_->start();
    tx[0] = address;
    i2c_->write((IR_ADDRESS << 1) & 0xFE, tx, num_data);
    wait_ms(1);
    //i2c_->stop();
    
    //i2c_->start();
    i2c_->read((IR_ADDRESS << 1) | 0x01, rx, num_data);
    wait_ms(1);
    //i2c_->stop();
    
    return rx[0];
}

void SI1143::write_reg(char address, char num_data) // Write a resigter
{  
    char tx[2];
    
    //i2c_->start();
    tx[0] = address;
    tx[1] = num_data;
    i2c_->write((IR_ADDRESS << 1) & 0xFE, tx, 2);
    wait_ms(1);
    //i2c_->stop();   
}

void SI1143::bias(int ready, int repeat)
{
    wait(ready);
    //bias1 = get_ps1(repeat);
    bias1 = 0;
    bias2 = get_ps2(repeat);
    bias3 = get_ps3(repeat);
}

int SI1143::get_ps1(int repeat) // Read the data for the first LED (Used in forced mode)
{
    int stack = 0;
    
    command(PSALS_FORCE);
    
    for(int r=repeat; r>0; r=r-1)
    {
        LowB = read_reg(PS1_DATA0,1);
        HighB = read_reg(PS1_DATA1,1);
        stack = stack + (HighB * 256) + LowB;
    }
    PS1 = stack / repeat;
    
    if(PS1 > bias1)
        PS1 = PS1 - bias1;
    else
        PS1 = 0;
    
    return PS1;
}

void SI1143::start_ps_auto()
{
    command(PS_AUTO);
}    

int SI1143::read_ps1() // Read the data for the first LED (Used in autonomous mode)
{
    

    LowB = read_reg(PS1_DATA0,1);
    HighB = read_reg(PS1_DATA1,1);
    PS1 = (HighB * 256) + LowB;
    
    if(PS1 > bias1)
        PS1 = PS1 - bias1;
    else
        PS1 = 0;
    
    return PS1;
}

int SI1143::get_ps2(int repeat) // Read the data for the second LED
{
    int stack = 0;
    
    command(PSALS_FORCE);
    
    for(int r=repeat; r>0; r=r-1)
    {
        LowB = read_reg(PS2_DATA0,1);
        HighB = read_reg(PS2_DATA1,1);
        stack = stack + (HighB * 256) + LowB;
    }
    PS2 = stack / repeat;
    
    if(PS2 > bias2)
        PS2 = PS2 - bias2;
    else
        PS2 = 0;
    
    return PS2;
}

int SI1143::get_ps3(int repeat) // Read the data for the third LED
{
    int stack = 0;
    
    command(PSALS_FORCE);
    
    for(int r=repeat; r>0; r=r-1)
    {
        LowB = read_reg(PS3_DATA0,1);
        HighB = read_reg(PS3_DATA1,1);
        stack = stack + (HighB * 256) + LowB;
    }
    PS3 = stack / repeat;
    
    if(PS3 > bias3)
        PS3 = PS3 - bias3;
    else
        PS3 = 0;
    
    return PS3;
}

int SI1143::get_vis(int repeat) // Read the data for ambient light
{
    int stack = 0;
    
    command(PSALS_FORCE);
    
    for(int r=repeat; r>0; r=r-1)
    {
        LowB = read_reg(ALS_VIS_DATA0,1);
        HighB = read_reg(ALS_VIS_DATA1,1);
        VIS = stack + (HighB * 256) + LowB;
    }
    VIS = stack / repeat;
    
    return VIS;
}

int SI1143::get_ir(int repeat) // Read the data for infrared light
{
    int stack = 0;
    
    command(PSALS_FORCE);
    
    for(int r=repeat; r>0; r=r-1)
    {
        LowB = read_reg(ALS_IR_DATA0,1);
        HighB = read_reg(ALS_IR_DATA1,1);
        IR = stack + (HighB * 256) + LowB;
    }
    IR = stack / repeat;
    
    return IR;
}

void SI1143::clear_int() // Clear Interrupt register when an interrupt occurs.
{
    write_reg(IRQ_STATUS, 0x3F); // Writes one to every interrupt status, thereby clearing them
}