File content as of revision 40:5ce51b7e3118:

#include "DW1000.h"

DW1000::DW1000(PinName MOSI, PinName MISO, PinName SCLK, PinName CS, PinName IRQ) : irq(IRQ), spi(MOSI, MISO, SCLK), cs(CS) {
    setCallbacks(NULL, NULL);
    
    deselect();                         // Chip must be deselected first
    spi.format(8,0);                    // Setup the spi for standard 8 bit data and SPI-Mode 0 (GPIO5, GPIO6 open circuit or ground on DW1000)
    spi.frequency(1000000);             // with a 1MHz clock rate (worked up to 49MHz in our Test)
    
    resetAll();                         // we do a soft reset of the DW1000 everytime the driver starts
    loadLDE();                          // important everytime DW1000 initialises/awakes otherwise the LDE algorithm must be turned of or there's receiving malfunction see User Manual LDELOAD on p22 & p158
    
    // Configuration TODO: make method for that
    writeRegister8(DW1000_SYS_CFG, 3, 0x20);    // enable auto reenabling receiver after error
    //writeRegister16(DW1000_TX_FCTRL, 1, 0x2800 | 0x0100 | 0x0080); // use 2048 symbols preable (0x2800), 16MHz pulse repetition frequency (0x0100), 110kbps bit rate (0x0080) see p.69 of DW1000 User Manual
    //writeRegister8(DW1000_SYS_CFG, 2, 0x40);    // enable special receiving option for 110kbps!! (0x40) see p.64 of DW1000 User Manual [DO NOT enable 1024 byte frames (0x03) becuase it generates disturbance of ranging don't know why...]
    
    irq.rise(this, &DW1000::ISR);       // attach interrupt handler to rising edge of interrupt pin from DW1000
}

void DW1000::setCallbacks(void (*callbackRX)(void), void (*callbackTX)(void)) {
    bool RX = false;
    bool TX = false;
    if (callbackRX) {
        DW1000::callbackRX.attach(callbackRX);
        RX = true;
    }
    if (callbackTX) {
        DW1000::callbackTX.attach(callbackTX);
        TX = true;
    }
    setInterrupt(RX,TX);
}

uint32_t DW1000::getDeviceID() {
    uint32_t result;
    readRegister(DW1000_DEV_ID, 0, (uint8_t*)&result, 4);
    return result;
}

uint64_t DW1000::getEUI() {
    uint64_t result;
    readRegister(DW1000_EUI, 0, (uint8_t*)&result, 8);
    return result;
}

void DW1000::setEUI(uint64_t EUI) {
    writeRegister(DW1000_EUI, 0, (uint8_t*)&EUI, 8);
}

float DW1000::getVoltage() {
    uint8_t buffer[7] = {0x80, 0x0A, 0x0F, 0x01, 0x00};             // algorithm form User Manual p57
    writeRegister(DW1000_RF_CONF, 0x11, buffer, 2);
    writeRegister(DW1000_RF_CONF, 0x12, &buffer[2], 1);
    writeRegister(DW1000_TX_CAL, 0x00, &buffer[3], 1);
    writeRegister(DW1000_TX_CAL, 0x00, &buffer[4], 1);
    readRegister(DW1000_TX_CAL, 0x03, &buffer[5], 2);               // get the 8-Bit readings for Voltage and Temperature
    float Voltage = buffer[5] * 0.0057 + 2.3;
    //float Temperature = buffer[6] * 1.13 - 113.0;                 // TODO: getTemperature was always ~35 degree with better formula/calibration see instance_common.c row 391
    return Voltage;
}

uint64_t DW1000::getStatus() {
    return readRegister40(DW1000_SYS_STATUS, 0);
}

uint64_t DW1000::getRXTimestamp() {
    return readRegister40(DW1000_RX_TIME, 0);
}

uint64_t DW1000::getTXTimestamp() {
    return readRegister40(DW1000_TX_TIME, 0);
}

void DW1000::sendString(char* message) {
    sendFrame((uint8_t*)message, strlen(message)+1);
}

void DW1000::receiveString(char* message) {
    readRegister(DW1000_RX_BUFFER, 0, (uint8_t*)message, getFramelength());  // get data from buffer
}

void DW1000::sendFrame(uint8_t* message, uint16_t length) {
    //if (length >= 1021) length = 1021;                            // check for maximim length a frame can have with 1024 Byte frames [not used, see constructor]
    if (length >= 125) length = 125;                                // check for maximim length a frame can have with 127 Byte frames
    writeRegister(DW1000_TX_BUFFER, 0, message, length);            // fill buffer
    
    uint8_t backup = readRegister8(DW1000_TX_FCTRL, 1);             // put length of frame
    length += 2;                                                    // including 2 CRC Bytes
    length = ((backup & 0xFC) << 8) | (length & 0x03FF);
    writeRegister16(DW1000_TX_FCTRL, 0, length);
    
    stopTRX();                                                      // stop receiving
    writeRegister8(DW1000_SYS_CTRL, 0, 0x02);                       // trigger sending process by setting the TXSTRT bit
    startRX();                                                      // enable receiver again
}

void DW1000::startRX() {
    writeRegister8(DW1000_SYS_CTRL, 0x01, 0x01);                    // start listening for preamble by setting the RXENAB bit
}

void DW1000::stopTRX() {
    writeRegister8(DW1000_SYS_CTRL, 0, 0x40);                       // disable tranceiver go back to idle mode
}

// PRIVATE Methods ------------------------------------------------------------------------------------
void DW1000::loadLDE() {                                            // initialise LDE algorithm LDELOAD User Manual p22
    writeRegister16(DW1000_PMSC, 0, 0x0301);                        // set clock to XTAL so OTP is reliable
    writeRegister16(DW1000_OTP_IF, 0x06, 0x8000);                   // set LDELOAD bit in OTP
    wait_us(150);
    writeRegister16(DW1000_PMSC, 0, 0x0200);                        // recover to PLL clock
}

void DW1000::resetRX() {    
    writeRegister8(DW1000_PMSC, 3, 0xE0);   // set RX reset
    writeRegister8(DW1000_PMSC, 3, 0xF0);   // clear RX reset
}

void DW1000::resetAll() {
    writeRegister8(DW1000_PMSC, 0, 0x01);   // set clock to XTAL
    writeRegister8(DW1000_PMSC, 3, 0x00);   // set All reset
    wait_us(10);                            // wait for PLL to lock
    writeRegister8(DW1000_PMSC, 3, 0xF0);   // clear All reset
}


void DW1000::setInterrupt(bool RX, bool TX) {
    writeRegister16(DW1000_SYS_MASK, 0, RX*0x4000 | TX*0x0080);  // RX good frame 0x4000, TX done 0x0080
}

void DW1000::ISR() {
    uint64_t status = getStatus();
    if (status & 0x4000) {                                          // a frame was received
        callbackRX.call();
        writeRegister16(DW1000_SYS_STATUS, 0, 0x6F00);              // clearing of receiving status bits
    }
    if (status & 0x80) {                                            // sending complete
        callbackTX.call();
        writeRegister8(DW1000_SYS_STATUS, 0, 0xF8);                 // clearing of sending status bits
    }
}

uint16_t DW1000::getFramelength() {
    uint16_t framelength = readRegister16(DW1000_RX_FINFO, 0);      // get framelength
    framelength = (framelength & 0x03FF) - 2;                       // take only the right bits and subtract the 2 CRC Bytes
    return framelength;
}

// SPI Interface ------------------------------------------------------------------------------------
uint8_t DW1000::readRegister8(uint8_t reg, uint16_t subaddress) {
    uint8_t result;
    readRegister(reg, subaddress, &result, 1);
    return result;
}

uint16_t DW1000::readRegister16(uint8_t reg, uint16_t subaddress) {
    uint16_t result;
    readRegister(reg, subaddress, (uint8_t*)&result, 2);
    return result;
}

uint64_t DW1000::readRegister40(uint8_t reg, uint16_t subaddress) {
    uint64_t result;
    readRegister(reg, subaddress, (uint8_t*)&result, 5);
    result &= 0xFFFFFFFFFF;                                 // only 40-Bit
    return result;
}

void DW1000::writeRegister8(uint8_t reg, uint16_t subaddress, uint8_t buffer) {
    writeRegister(reg, subaddress, &buffer, 1);
}

void DW1000::writeRegister16(uint8_t reg, uint16_t subaddress, uint16_t buffer) {
    writeRegister(reg, subaddress, (uint8_t*)&buffer, 2);
}

void DW1000::readRegister(uint8_t reg, uint16_t subaddress, uint8_t *buffer, int length) {
    setupTransaction(reg, subaddress, false);
    for(int i=0; i<length; i++)                             // get data
        buffer[i] = spi.write(0x00);
    deselect();
}

void DW1000::writeRegister(uint8_t reg, uint16_t subaddress, uint8_t *buffer, int length) {
    setupTransaction(reg, subaddress, true);
    for(int i=0; i<length; i++)                             // put data
        spi.write(buffer[i]);
    deselect();
}

void DW1000::setupTransaction(uint8_t reg, uint16_t subaddress, bool write) {
    reg |=  (write * DW1000_WRITE_FLAG);                                        // set read/write flag
    select();
    if (subaddress > 0) {                                                       // there's a subadress, we need to set flag and send second header byte
        spi.write(reg | DW1000_SUBADDRESS_FLAG);
        if (subaddress > 0x7F) {                                                // sub address too long, we need to set flag and send third header byte
            spi.write((uint8_t)(subaddress & 0x7F) | DW1000_2_SUBADDRESS_FLAG); // and 
            spi.write((uint8_t)(subaddress >> 7));
        } else {
            spi.write((uint8_t)subaddress);
        }
    } else {
        spi.write(reg);                                                         // say which register address we want to access
    }
}

void DW1000::select() {     // always called to start an SPI transmission
    irq.disable_irq();      // disable interrupts from DW1000 during SPI becaus this leads to crashes!      TODO: if you have other interrupt handlers attached on the micro controller, they could also interfere.
    cs = 0;                 // set Cable Select pin low to start transmission
}
void DW1000::deselect() {   // always called to end an SPI transmission
    cs = 1;                 // set Cable Select pin high to stop transmission
    irq.enable_irq();       // reenable the interrupt handler
}