File content as of revision 47:199042980678:

#include "hardwareIO.h"

HardwareIO IO; // preintantiation of cross-file global object IO

// --------------------------------------  (0) SETUP ALL IO (call this in the setup() function in main program)

Serial pc(USBTX, USBRX); // tx, rx
LocalFileSystem local("local");               // Create the local filesystem under the name "local"

SPI spiDAC(MOSI_PIN, MISO_PIN, SCK_PIN); // mosi, miso, sclk
DigitalOut csDAC(CS_DAC_MIRRORS);

DigitalOut Laser_Red(LASER_RED_PIN); // NOTE: this is NOT the lock in sensing laser (actually, not used yet)
DigitalOut Laser_Green(LASER_GREEN_PIN);
DigitalOut Laser_Blue(LASER_BLUE_PIN);

// Some manual controls over the hardware function:
InterruptIn switchOne(SWITCH_ONE);
DigitalOut ledSwitchOne(LED_SWITCH_ONE);
InterruptIn switchTwo(SWITCH_TWO);
AnalogIn ainPot(POT_ANALOG_INPUT);   // I cannot use this directly because the adc is being used by the locking. We have to re-setup it (see updatePotValue())

// Testing leds (for debugging):
DigitalOut myLed1(LED1); // note: LED1/2/3/4 are defined in mbed.h, and correspond to mbed pins 32, 34, 35 and 37
DigitalOut myLed2(LED2);
DigitalOut myLed3(LED3);
DigitalOut myLed4(LED4);

void HardwareIO::init(void)
{
    setLaserLockinPower(1); // this may be always ON (the IR laser). But we may want to switch it off sometimes...
    Laser_Red = 0; // note: this is not the lockin-laser! (in the future, the lock in laser will be infrared...)
    Laser_Green = 0;
    Laser_Blue = 0;

    // Test leds:
    myLed1=0;
    myLed2=0;
    myLed3=0;
    myLed4=0;

    //Serial Communication setup:
    pc.baud(SERIAL_SPEED);

    // Setup for lock-in amplifier and pwm references:
    setLaserLockinPower(1);// actually this is the Red laser in the hardware
    lockin.init();

    // Setup for DAC control to move the mirrors:
    // Set spi for 8 bit data, high steady state clock,
    // second edge capture, with a 10MHz clock rate:
    csDAC = 1;
    spiDAC.format(16,0);
    spiDAC.frequency(16000000);

    // default initial mirror position:
    writeOutX(CENTER_AD_MIRROR_X);
    writeOutY(CENTER_AD_MIRROR_Y);

    // Load LUT table:
    setLUT();

    // Set interrupts on RAISING edge for button-switch functions:
    // Note: The pin input will be logic '0' for any voltage on the pin below 0.8v, and '1' for any voltage above 2.0v.
    // By default, the InterruptIn is setup with an internal pull-down resistor, but for security and clarity I will do it explicitly here:
    switchOne.mode(PullUp); // pull down seems not very good
    switchTwo.mode(PullUp);
    switchOne.fall(this, &HardwareIO::switchOneInterrupt);  // attach the address of the flip function to the falling edge
    switchTwo.fall(this, &HardwareIO::switchTwoInterrupt);  // attach the address of the flip function to the falling edge
    switchOneState=true;
    switchTwoState=false;
    switchOneChange=false;
    switchTwoChange=false;

    setSwitchOneState(true); //equal to switchOneState=true, plus set led value. False means fixed threshold, true AUTO THRESHOLD (will be the default mode)

    // Read and update pot value:
    // updatePotValue(); // the value will be ajusted in the range 0-255
}

void HardwareIO::setSwitchOneState(bool newstate)
{
    switchOneState=newstate;
    ledSwitchOne=(switchOneState? 1 :0);
}

// these ISR could do more (like debouncing).
// For the time being, I will debounce electrically with a small capacitor.
void HardwareIO::switchOneInterrupt()
{
    switchOneState=!switchOneState;
    ledSwitchOne=(switchOneState? 1 :0); // this switch has a built-in led
    switchOneChange=true;
}
void HardwareIO::switchTwoInterrupt()
{
    switchTwoState=!switchTwoState;
    switchTwoChange=true;
}

bool HardwareIO::switchOneCheck(bool& state)
{
    if (switchOneChange) {
        switchOneChange=false;
        state=switchOneState;
        return(true);
    } else
        return(false);
}

bool HardwareIO::switchTwoCheck(bool& state)
{
    if (switchTwoChange) {
        switchTwoChange=false;
        state=switchTwoState;
        return(true);
    } else return(false);
}

unsigned char HardwareIO::updatePotValue()   // this will update the pot value, and return it too.
{
    //The value will be ajusted in the range 0-255
    //The 0.0v to 3.3v range of the AnalogIn is represented in software as a normalised floating point number from 0.0 to 1.0.
    potValue=(unsigned char )(ainPot*255);

/* USING the adc library: 
    // unset fast adc for lockin, and set normal adc for conversion from analog input pin:
    lockin.setADC_forLockin(0);
    adc.setup(POT_ANALOG_INPUT,1);

    wait(1);

    //Measure pin POT_ANALOG_INPUT
    adc.select(POT_ANALOG_INPUT);
    //Start ADC conversion
    adc.start();
    //Wait for it to complete
    while(!adc.done(POT_ANALOG_INPUT));
    potValue=adc.read(POT_ANALOG_INPUT);

    //Unset pin POT_ANALOG_INPUT
    adc.setup(POT_ANALOG_INPUT,0);

    lockin.setADC_forLockin(1);
    // wait(1);
*/

 // Attention! reading using the AnalogIn library seems to break my burst reading mode. So, we need to re-set it: 
    lockin.setADC_forLockin(1);
    
    return(potValue);
}

//write on the first DAC, output A (mirror X)
void HardwareIO::writeOutX(unsigned short value)
{
    if(value > MAX_AD_MIRRORS) value = MAX_AD_MIRRORS;
    if(value < MIN_AD_MIRRORS) value = MIN_AD_MIRRORS;

    value |= 0x7000;
    value &= 0x7FFF;

    csDAC = 0;
    spiDAC.write(value);
    csDAC = 1;
}

//write on the first DAC, output B (mirror Y)
void HardwareIO::writeOutY(unsigned short value)
{
    if(value > MAX_AD_MIRRORS) value = MAX_AD_MIRRORS;
    if(value < MIN_AD_MIRRORS) value = MIN_AD_MIRRORS;

    value |= 0xF000;
    value &= 0xFFFF;

    csDAC = 0;
    spiDAC.write(value);
    csDAC = 1;
}

void HardwareIO::setLaserLockinPower(int powerValue)
{
    if(powerValue > 0) {
        lockin.setLaserPower(true);
    } else {
        lockin.setLaserPower(false);
    }
}

void HardwareIO::setRedPower(int powerValue)
{
    if(powerValue > 0) {
        Laser_Red = 1;
    } else {
        Laser_Red = 0;
    }
}
void HardwareIO::setGreenPower(int powerValue)
{
    if(powerValue > 0) {
        Laser_Green = 1;
    } else {
        Laser_Green = 0;
    }
}
void HardwareIO::setBluePower(int powerValue)
{
    if(powerValue > 0) {
        Laser_Blue = 1;
    } else {
        Laser_Blue = 0;
    }
}


void HardwareIO::setRGBPower(unsigned char color)  // NOTE: this do NOT affect the power of the lockin laser...
{
    // lockin.setLaserPower((color&0x04)>0? true : false);
    Laser_Red=(color&0x04)>>2;
    Laser_Green=(color&0x02)>>1;
    Laser_Blue =color&0x01;
}

// Attention: we should stop the displaying engine lsd before calling this (if we want, otherwise it will continue showing the
// displayed objects/scene, but it will be weird) - this is done in the WRAPPERS methods.
void HardwareIO::showLimitsMirrors(unsigned short pointsPerLine, unsigned short durationSecs)
{
    //unsigned short pointsPerLine=150;
    int shiftX = (MAX_AD_MIRRORS - MIN_AD_MIRRORS) / pointsPerLine;
    int shiftY = (MAX_AD_MIRRORS - MIN_AD_MIRRORS) / pointsPerLine;

    setRGBPower(0x07);// all displaying lasers ON

    //for (int repeat=0; repeat<times; repeat++) {

    Timer t;
    t.start();
    while(t.read_ms()<durationSecs*1000) {

        writeOutX(MIN_AD_MIRRORS);
        writeOutY(MIN_AD_MIRRORS);

        for(int j=0; j<pointsPerLine; j++) {
            wait_us(200);//delay between each points
            writeOutY(j*shiftY + MIN_AD_MIRRORS);
        }

        writeOutX(MIN_AD_MIRRORS);
        writeOutY(MAX_AD_MIRRORS);
        for(int j=0; j<pointsPerLine; j++) {
            wait_us(200);//delay between each points
            writeOutX(j*shiftX + MIN_AD_MIRRORS);
        }

        writeOutX(MAX_AD_MIRRORS);
        writeOutY(MAX_AD_MIRRORS);
        for(int j=0; j<pointsPerLine; j++) {
            wait_us(200);//delay between each points
            writeOutY(-j*shiftX + MAX_AD_MIRRORS);
        }

        writeOutX(MAX_AD_MIRRORS);
        writeOutY(MIN_AD_MIRRORS);
        for(int j=0; j<pointsPerLine; j++) {
            wait_us(200);//delay between each points
            writeOutX(-j*shiftX + MAX_AD_MIRRORS);
        }

    }
    t.stop();
    Laser_Green=0;
}

void HardwareIO::scan_serial(unsigned short pointsPerLine)
{
    //scan the total surface with a custom resolution
    //send the lockin value for each point as a byte on the serial port to the PC
    //use "scanSLP_save" to see the data on processing

    int shiftX = (MAX_AD_MIRRORS - MIN_AD_MIRRORS) / pointsPerLine;
    int shiftY = (MAX_AD_MIRRORS - MIN_AD_MIRRORS) / pointsPerLine;

    for(int j=0; j<pointsPerLine; j++) {
        writeOutX(MIN_AD_MIRRORS);
        writeOutY(j*shiftY + MIN_AD_MIRRORS);

        wait_us(300);//begining of line delay
        for(int i=0; i<pointsPerLine; i++) {
            writeOutX(i*shiftX + MIN_AD_MIRRORS);

            wait_us(200);//delay between each points

            // SEND A VALUE BETWEEN 0 and 255:
            pc.putc(int(255.0*lockin.getMedianValue()/4095));//printf("%dL",int(valueLockin*255));//pc.putc(int(lockin*255));//
        }
    }
}

//load Look-up Table from LUT.TXT file
//or create the file with scanLUT() if not existing.
void HardwareIO::setLUT()
{

    FILE *fp = fopen(LUT_FILENAME, "r");  // Open file on the local file system for writing
    if(fp) {
        //load the file into the lut table; keep the SAME resolution!
        fread(lut,sizeof(uint16),LUT_RESOLUTION*LUT_RESOLUTION,fp);
        fclose(fp);
    } else {
        //fclose(fp);
        //if the file "LUT.TXT" doesn't exist, create one with scanLUT()
        lockin.setLaserPower(true);
        scanLUT();
    }

}

//scan the total surface with a fixed 2^x resolution
//create the Look-Up Table used to "flatten" the scan according to the position
//
//To Do: maybe detect high frequency to be sure the area is clean and empty?
void HardwareIO::scanLUT()
{

    //reset lut table
    for(int j=0; j<LUT_RESOLUTION; j++) {
        for(int i=0; i<LUT_RESOLUTION; i++) {
            lut[i][j] =0;
        }
    }

    int delayScanning = 300; //in us

    //define the distance between each points (from 0 to 4096) and the offset (here 0)
    float shiftX = 1.0*(MAX_AD_MIRRORS - MIN_AD_MIRRORS) / (LUT_RESOLUTION-1);
    float shiftY = 1.0*(MAX_AD_MIRRORS - MIN_AD_MIRRORS) / (LUT_RESOLUTION-1);
    float offsetX = MIN_AD_MIRRORS;
    float offsetY = MIN_AD_MIRRORS;

    //move the mirrors to the first position
    writeOutX(MAX_AD_MIRRORS);
    writeOutY(MIN_AD_MIRRORS);
    wait_us(500);

    float x, y;

    //scan the surface NB_SCANS times
    //the total value in lut[i][j] shouldn't exceed uint16 !!!
    for(int loop=0; loop<NB_SCANS; loop++) {
        for(int j=0; j<LUT_RESOLUTION; j++) {
            y = shiftY*j + offsetY ;
            writeOutY(int(y));
            //scan from right to left
            for(int i=LUT_RESOLUTION-1; i>=0; i--) {
                x = shiftX*i + offsetX;
                writeOutX(int(x));
                wait_us(delayScanning);
                lut[i][j] += lockin_read();
            }
            //re-scan from left to right
            for(int i=0; i<LUT_RESOLUTION; i++) {
                x = shiftX*i + offsetX;
                writeOutX(int(x));
                wait_us(delayScanning);
                lut[i][j] += lockin_read();
            }
        }
    }


    //save tab in file
    FILE *fp;
#ifdef LUT_FILENAME
    fp = fopen(LUT_FILENAME, "w");  // Open file on the local file system for writing
    fwrite(lut,sizeof(uint16),LUT_RESOLUTION*LUT_RESOLUTION,fp);
    fclose(fp); //close the file (the mBed will appear connected again)
#endif

#ifdef LUT_H_FILENAME
    //save tab in Human readable file (not used by the program, this is just for checking)
    // NOTE: we divide the content of the lut table by NB_SCANS, for easy reading (values should be between 0-4095)
    fp = fopen(LUT_H_FILENAME, "w");  // Open file on the local file system for writing
    fprintf(fp, "scan resolution: %d x %d\r\n",LUT_RESOLUTION, LUT_RESOLUTION);
    for(int j=0; j<LUT_RESOLUTION; j++) {
        for(int i=0; i<LUT_RESOLUTION; i++) {
            fprintf(fp, "X=%d,\tY=%d,\tI=%d\t \r\n", int(shiftX*i + offsetX), int(shiftY*j + offsetY), int(1.0*lut[i][j]/NB_SCANS) );
        }
    }
    fclose(fp); //close the file (the mBed will appear connected again)
#endif

}


//Return the lockin value "corrected with the Look-UpTable" - this means a RATIO between two reflectivities (and normally, this is <1).
float HardwareIO::lockInCorrectedValue(unsigned short x, unsigned short y)
{
//*******Correction using DIRECT approximation
#ifdef LUT_DIRECT
    return 2.0* NB_SCANS * lockin_read() / (lut[x >> LUT_BITS_SHIFT][y >> LUT_BITS_SHIFT]); // 2 * NB_SCANS is the number of recorded sample added to one position of the LUT (scan is performed twice: left-right and right-left)
#endif

//*******Correction using BILINEAR approximation
#ifdef LUT_BILINEAR
    unsigned short X = x >> LUT_BITS_SHIFT; //mirror "x" is 12bits, LUT "X" needs 4bits when lut is 17x17
    unsigned short Y = y >> LUT_BITS_SHIFT; //mirror "y" is 12bits, LUT "Y" needs 4bits when lut is 17x17
    float dx = 1.0*(x & LUT_BITS_MASK)/(LUT_BITS_MASK+1); //weight to apply on X (mask with 255 and norm)
    float dy = 1.0*(y & LUT_BITS_MASK)/(LUT_BITS_MASK+1); //weight to apply on Y (mask with 255 and norm)

    //Wheighted mean approximation of the Look-Up Table at the position (x,y):
    float wmLUT = (1-dy)*( (1-dx)*lut[X][Y] + dx*lut[X+1][Y] ) + dy*( (1-dx)*lut[X][Y+1] + dx*lut[X+1][Y+1] );

    return 2.0* NB_SCANS * lockin_read() / wmLUT;// 2 * NB_SCANS is the number of recorded sample added to one position of the LUT (scan is performed twice: left-right and right-left)
#endif

//*******Correction using LINEAR approximation
#ifdef LUT_LINEAR
    unsigned short X = x >> LUT_BITS_SHIFT; //mirror "x" is 12bits, LUT "X" needs 4bits when lut is 17x17
    unsigned short Y = y >> LUT_BITS_SHIFT; //mirror "y" is 12bits, LUT "Y" needs 4bits when lut is 17x17
    float dx = 1.0*(x & LUT_BITS_MASK)/(LUT_BITS_MASK+1); //weight to apply on X (mask with 255 and norm)
    float dy = 1.0*(y & LUT_BITS_MASK)/(LUT_BITS_MASK+1); //weight to apply on Y (mask with 255 and norm)
    float linearLUT, dzx, dzy;

    if(dx>dy) { //if the position is on the "top-right" triangle
        dzx = (lut[X+1][Y] - lut[X][Y]) * dx;
        dzy = (lut[X+1][Y+1] - lut[X+1][Y]) * dy;
    } else { //if the position is on the "bottom-left" triangle
        dzy = (lut[X][Y+1] - lut[X][Y]) * dy;
        dzx = (lut[X+1][Y+1] - lut[X][Y+1]) * dx;
    }

    //linear approximation of the Look-Up Table at the position (x,y):
    linearLUT = lut[X][Y] + dzx + dzy;
    return 2.0* NB_SCANS * lockin_read() / linearLUT; // 2 * NB_SCANS is the number of recorded sample added to one position of the LUT (scan is performed twice: left-right and right-left)

#endif

//*******No corrections, just return the value divided by 4096 (this means we are assuming that the surface is everywhere perfectly reflective - we supposedly get the max value always)
#ifdef NO_LUT
    return 1.0* lockin_read()/4096;
#endif

}