////  SerialInterface.cpp//  2012 by Philip Rosedale for High Fidelity Inc.////  Read interface data from the gyros/accelerometer board using SerialUSB////  Channels are received in the following order (integer 0-4096 based on voltage 0-3.3v)////  0 - AIN 15:  Pitch Gyro (nodding your head 'yes')//  1 - AIN 16:  Yaw Gyro (shaking your head 'no')//  2 - AIN 17:  Roll Gyro (looking quizzical, tilting your head)//  3 - AIN 18:  Lateral acceleration (moving from side-to-side in front of your monitor)//  4 - AIN 19:  Up/Down acceleration (sitting up/ducking in front of your monitor)//  5 - AIN 20:  Forward/Back acceleration (Toward or away from your monitor)// #include "SerialInterface.h" #ifdef __APPLE__#include <regex.h>#include <sys/time.h>#include <string>#endif const int MAX_BUFFER = 255;char serialBuffer[MAX_BUFFER];int serialBufferPos = 0; const int ZERO_OFFSET = 2048;const short NO_READ_MAXIMUM_MSECS = 3000;const short SAMPLES_TO_DISCARD = 100;               //  Throw out the first few samplesconst int GRAVITY_SAMPLES = 60;                     //  Use the first samples to compute gravity vector const bool USING_INVENSENSE_MPU9150 = 1; void SerialInterface::pair() {    #ifdef __APPLE__    // look for a matching gyro setup    DIR *devDir;    struct dirent *entry;    int matchStatus;    regex_t regex;        // for now this only works on OS X, where the usb serial shows up as /dev/tty.usb*    if((devDir = opendir("/dev"))) {        while((entry = readdir(devDir))) {            regcomp(&regex, "tty\\.usb", REG_EXTENDED|REG_NOSUB);            matchStatus = regexec(&regex, entry->d_name, (size_t) 0, NULL, 0);            if (matchStatus == 0) {                char *serialPortname = new char[100];                sprintf(serialPortname, "/dev/%s", entry->d_name);                                initializePort(serialPortname, 115200);                                delete [] serialPortname;            }            regfree(&regex);        }        closedir(devDir);    }    #endif} //  connect to the serial portvoid SerialInterface::initializePort(char* portname, int baud) {#ifdef __APPLE__    _serialDescriptor = open(portname, O_RDWR | O_NOCTTY | O_NDELAY);        printLog("Opening SerialUSB %s: ", portname);        if (_serialDescriptor == -1) {        printLog("Failed.\n");        return;    }        struct termios options;    tcgetattr(_serialDescriptor, &options);        switch(baud) {		case 9600: cfsetispeed(&options,B9600);			cfsetospeed(&options,B9600);			break;		case 19200: cfsetispeed(&options,B19200);			cfsetospeed(&options,B19200);			break;		case 38400: cfsetispeed(&options,B38400);			cfsetospeed(&options,B38400);			break;		case 115200: cfsetispeed(&options,B115200);			cfsetospeed(&options,B115200);			break;		default:cfsetispeed(&options,B9600);			cfsetospeed(&options,B9600);			break;    }        options.c_cflag |= (CLOCAL | CREAD);    options.c_cflag &= ~PARENB;    options.c_cflag &= ~CSTOPB;    options.c_cflag &= ~CSIZE;    options.c_cflag |= CS8;    tcsetattr(_serialDescriptor, TCSANOW, &options);        if (USING_INVENSENSE_MPU9150) {        // block on invensense reads until there is data to read        int currentFlags = fcntl(_serialDescriptor, F_GETFL);        fcntl(_serialDescriptor, F_SETFL, currentFlags & ~O_NONBLOCK);                // there are extra commands to send to the invensense when it fires up                // this takes it out of SLEEP        write(_serialDescriptor, "WR686B01\n", 9);                // delay after the wakeup        usleep(10000);                // this disables streaming so there's no garbage data on reads        write(_serialDescriptor, "SD\n", 3);                // delay after disabling streaming        usleep(10000);                // flush whatever was produced by the last two commands        tcflush(_serialDescriptor, TCIOFLUSH);    }        printLog("Connected.\n");    resetSerial();        active = true; #endif} //  Render the serial interface channel values onscreen as vertical linesvoid SerialInterface::renderLevels(int width, int height) {    char val[40];    if (USING_INVENSENSE_MPU9150) {        //  For invensense gyros, render as horizontal bars        const int LEVEL_CORNER_X = 10;        const int LEVEL_CORNER_Y = 200;                // Draw the numeric degree/sec values from the gyros        sprintf(val, "Yaw   %4.1f", _lastYawRate);        drawtext(LEVEL_CORNER_X, LEVEL_CORNER_Y, 0.10, 0, 1.0, 1, val, 0, 1, 0);        sprintf(val, "Pitch %4.1f", _lastPitchRate);        drawtext(LEVEL_CORNER_X, LEVEL_CORNER_Y + 15, 0.10, 0, 1.0, 1, val, 0, 1, 0);        sprintf(val, "Roll  %4.1f", _lastRollRate);        drawtext(LEVEL_CORNER_X, LEVEL_CORNER_Y + 30, 0.10, 0, 1.0, 1, val, 0, 1, 0);        sprintf(val, "X     %4.3f", _lastAccelX);        drawtext(LEVEL_CORNER_X, LEVEL_CORNER_Y + 45, 0.10, 0, 1.0, 1, val, 0, 1, 0);        sprintf(val, "Y     %4.3f", _lastAccelY);        drawtext(LEVEL_CORNER_X, LEVEL_CORNER_Y + 60, 0.10, 0, 1.0, 1, val, 0, 1, 0);        sprintf(val, "Z     %4.3f", _lastAccelZ);        drawtext(LEVEL_CORNER_X, LEVEL_CORNER_Y + 75, 0.10, 0, 1.0, 1, val, 0, 1, 0);                //  Draw the levels as horizontal lines                const int LEVEL_CENTER = 150;        const float ACCEL_VIEW_SCALING = 50.f;        glLineWidth(2.0);        glColor4f(1, 1, 1, 1);        glBegin(GL_LINES);        // Gyro rates        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER, LEVEL_CORNER_Y - 3);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER + _lastYawRate, LEVEL_CORNER_Y - 3);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER, LEVEL_CORNER_Y + 12);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER + _lastPitchRate, LEVEL_CORNER_Y + 12);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER, LEVEL_CORNER_Y + 27);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER + _lastRollRate, LEVEL_CORNER_Y + 27);        // Acceleration        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER, LEVEL_CORNER_Y + 42);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER + (int)((_lastAccelX - _gravity.x)* ACCEL_VIEW_SCALING),                   LEVEL_CORNER_Y + 42);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER, LEVEL_CORNER_Y + 57);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER + (int)((_lastAccelY - _gravity.y) * ACCEL_VIEW_SCALING),                   LEVEL_CORNER_Y + 57);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER, LEVEL_CORNER_Y + 72);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER + (int)((_lastAccelZ - _gravity.z) * ACCEL_VIEW_SCALING),                   LEVEL_CORNER_Y + 72);         glEnd();        //  Draw green vertical centerline        glColor4f(0, 1, 0, 0.5);        glBegin(GL_LINES);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER, LEVEL_CORNER_Y - 6);        glVertex2f(LEVEL_CORNER_X + LEVEL_CENTER, LEVEL_CORNER_Y + 30);        glEnd();    }} void convertHexToInt(unsigned char* sourceBuffer, int& destinationInt) {    unsigned int byte[2];        for(int i = 0; i < 2; i++) {        sscanf((char*) sourceBuffer + 2 * i, "%2x", &byte[i]);    }        int16_t result = (byte[0] << 8);    result += byte[1];        destinationInt = result;}void SerialInterface::readData() {#ifdef __APPLE__        int initialSamples = totalSamples;        if (USING_INVENSENSE_MPU9150) {         unsigned char sensorBuffer[36];                // ask the invensense for raw gyro data        write(_serialDescriptor, "RD683B0E\n", 9);        read(_serialDescriptor, sensorBuffer, 36);                int accelXRate, accelYRate, accelZRate;                convertHexToInt(sensorBuffer + 6, accelZRate);        convertHexToInt(sensorBuffer + 10, accelYRate);        convertHexToInt(sensorBuffer + 14, accelXRate);                const float LSB_TO_METERS_PER_SECOND2 = 1.f / 16384.f * 9.80665f;                                                                //  From MPU-9150 register map, with setting on                                                                //  highest resolution = +/- 2G                _lastAccelX = ((float) accelXRate) * LSB_TO_METERS_PER_SECOND2;        _lastAccelY = ((float) accelYRate) * LSB_TO_METERS_PER_SECOND2;        _lastAccelZ = ((float) -accelZRate) * LSB_TO_METERS_PER_SECOND2;                int rollRate, yawRate, pitchRate;                convertHexToInt(sensorBuffer + 22, rollRate);        convertHexToInt(sensorBuffer + 26, yawRate);        convertHexToInt(sensorBuffer + 30, pitchRate);                //  Convert the integer rates to floats        const float LSB_TO_DEGREES_PER_SECOND = 1.f / 16.4f;     //  From MPU-9150 register map, 2000 deg/sec.        const float PITCH_BIAS = 2.0;                            //  Strangely, there is a small DC bias in the                                                                 //  invensense pitch reading.  Gravity?                _lastRollRate = ((float) rollRate) * LSB_TO_DEGREES_PER_SECOND;        _lastYawRate = ((float) yawRate) * LSB_TO_DEGREES_PER_SECOND;        _lastPitchRate = ((float) -pitchRate) * LSB_TO_DEGREES_PER_SECOND + PITCH_BIAS;                //  Accumulate an initial reading for gravity        //  Use a set of initial samples to compute gravity        if (totalSamples < GRAVITY_SAMPLES) {            _gravity.x += _lastAccelX;            _gravity.y += _lastAccelY;            _gravity.z += _lastAccelZ;        }        if (totalSamples == GRAVITY_SAMPLES) {            _gravity /= (float) totalSamples;            printLog("Gravity: %f\n", glm::length(_gravity));        }         totalSamples++;    }         if (initialSamples == totalSamples) {                timeval now;        gettimeofday(&now, NULL);                if (diffclock(&lastGoodRead, &now) > NO_READ_MAXIMUM_MSECS) {            printLog("No data - Shutting down SerialInterface.\n");            resetSerial();        }    } else {        gettimeofday(&lastGoodRead, NULL);    }#endif} void SerialInterface::resetSerial() {#ifdef __APPLE__    active = false;    totalSamples = 0;    _gravity = glm::vec3(0, 0, 0);        gettimeofday(&lastGoodRead, NULL);    #endif}