File content as of revision 3:782a719f47a5:

#include "AMS_CCS811.h"


AMS_CCS811::AMS_CCS811(I2C * i2c, PinName n_wake_pin) { 
    _n_wake_out = new (std::nothrow) DigitalOut(n_wake_pin);
    _i2c = i2c;
    
    set_defaults();
}
            
AMS_CCS811::AMS_CCS811(I2C * i2c, PinName n_wake_pin, I2C * ens210_i2c) {
    _n_wake_out = new (std::nothrow) DigitalOut(n_wake_pin);
    _i2c = i2c;
    _ens210_i2c = ens210_i2c;
    
    set_defaults();
    
}
              
AMS_CCS811::~AMS_CCS811() {
    delete _n_wake_out;
    delete _addr_out;
    delete _int_data;
}

bool AMS_CCS811::init() {
    return true;
}

bool AMS_CCS811::mode(OP_MODES mode) {
    OP_MODES old = _mode;               // incase the write fails, to roll back
    _mode = mode;
    
    bool success = write_config();
    if (!success)
        _mode = old;
    
    return success;
}

AMS_CCS811::OP_MODES AMS_CCS811::mode() {
    OP_MODES result = _mode;                        // rather not rely on this, but just incase the read fails
    
    read_config_result read_result = read_config();
    if (read_result.success) {
        int mode = (read_result.byte >> 4) & 0b111;
        result = mode > 4 ? INVALID : (OP_MODES)mode;
    } // todo ... add a new "last error" here
    
    return result;
}

bool AMS_CCS811::addr_mode(bool high) { 
    _addr_dir = high;
    if (_addr_out != NULL) *_addr_out = _addr_dir;
    
    update_slave_addr();
    
    return addr_mode() == high;
}

bool AMS_CCS811::addr_mode() {
    if (_addr_out != NULL) {
        _addr_dir = *_addr_out; 
    }
    
    return _addr_dir;
}

bool AMS_CCS811::addr_pin(PinName pin) {
    _addr_out = _addr_out == NULL ? new (std::nothrow) DigitalOut(pin) : new (_addr_out) DigitalOut(pin);
    addr_mode(_addr_dir);
    
    return _addr_out != NULL;
}

bool AMS_CCS811::n_wake_pin(PinName pin) {
    _n_wake_out = _n_wake_out == NULL ? new (std::nothrow) DigitalOut(pin) : new (_n_wake_out) DigitalOut(pin);
    return _n_wake_out != NULL;
}

bool AMS_CCS811::env_data(float humid, float temp) {
    return true;
}


AMS_CCS811::DATA_STATUS AMS_CCS811::has_new_data() {
    return (DATA_STATUS) 0;
}

uint16_t AMS_CCS811::co2_read() {
    return 0;
}

uint16_t AMS_CCS811::tvoc_read() {
    return 0;
}

uint16_t AMS_CCS811::raw_read() {
    return 0;
}

const char * AMS_CCS811::last_error() {
    return "";
}

bool AMS_CCS811::enable_interupt(bool enable) {
    bool old = _int_data_enabled;   // incase the write fails, to roll back
    _int_data_enabled = enable;
    
    bool success = write_config();
    if (!success)
        _int_data_enabled = old;
    
    return success;

}

bool AMS_CCS811::interupt_enabled() {
    bool enabled = _int_data_enabled;                        // rather not rely on this, but just incase the read fails
    
    read_config_result read_result = read_config();
    if (read_result.success) {
        enabled = (read_result.byte >> 3) & 1;
    } // todo ... add a new "last error" here? or maybe the read method itself should set that.
    
    return enabled;
}

bool AMS_CCS811::interrupt_pin(PinName pin) {
    bool success = false;
    
    _int_data = _int_data == NULL ? new (std::nothrow) InterruptIn(pin) : new (_int_data) InterruptIn(pin);
    if (_int_data != NULL) {
        _int_data->fall(callback(this, &AMS_CCS811::_isr_data));
        success = true;
    }
    
    return success;
}




/** Private **/

bool AMS_CCS811::set_defaults() {
    if (_mode == NULL) 
        _mode = CONFIG_OP_MODE;
    if (_addr_dir == NULL)
        _addr_dir = CONFIG_ADDR_DIR;
    if (_int_data_enabled == NULL)
        _int_data_enabled = CONFIG_INTR;
    if (_ens210_poll_split == NULL)
        _ens210_poll_split = CONFIG_ENS210_POLL;
        
    update_slave_addr();
        
    return write_config();
}

void AMS_CCS811::update_slave_addr() {
    slave_addr = addr_mode() ? SLAVE_ADDR_RAW_H : SLAVE_ADDR_RAW_L; 
}
        
void AMS_CCS811::_isr_data() {
    _isr_data_fp.call();
}

bool AMS_CCS811::write_config() {
    char cmd[1] = {0 | (_int_data_enabled << 3) | (_mode << 4)};
    return i2c_write(SYS_MODE, cmd, 1) == 1;
}

AMS_CCS811::read_config_result AMS_CCS811::read_config() {
    read_config_result result;
    char byte[1];
    if (i2c_read(SYS_MODE, byte, 1) == 1) {
        result.success = true;
        result.byte = byte[1];
    }
    
    return result;
}

int AMS_CCS811::i2c_read(char reg_addr, char* output, int len) {
    
    int read_count = 0;
    if (_n_wake_out != NULL) {                                          // check nWAKE pin is set 
        if (_i2c != NULL) {                                             // check I2C interface is set
            _i2c->start();                                              // send start condition for write
            if(_i2c->write(SLAVE_ADDR_W) == 1) {                        // write slave address with write bit
                if(_i2c->write(reg_addr) == 1) {                        // write register address
                    _i2c->start();                                      // send another start condition for read
                    if(_i2c->write(SLAVE_ADDR_R) == 1) {                // write slave address with read bit
                        for (int i = 0; i < len; i++) {                 // read len bytes
                            output[i] = _i2c->read(i < len-1 ? 1 : 0);  // ack all reads aside from the final one (i == len-1)
                            read_count++;
                        }
                    }
                }
            }
            _i2c->stop();                                               // send stop condition 
        }
    }
    
    return read_count;
}

int AMS_CCS811::i2c_write(char reg_addr, char* input, int len) {        // to do... error reporting
    
    int write_count = 0;
    if (_n_wake_out != NULL) {                                          // check nWAKE pin is set
        if (_i2c != NULL) {                                             // check I2C interface is set
            _i2c->start();                                              // send start condition for write
            if(_i2c->write(SLAVE_ADDR_W) == 1) {                        // write slave address
                if(_i2c->write(reg_addr) == 1) {                        // write register address
                    for (int i = 0; i < len; i++) {                     // write len bytes
                        if(_i2c->write(input[i]) == 1) write_count++;   // write each byte, if successful increment count
                    }
                }
            }
            _i2c->stop();                                               // send stop condition 
        }
    }
    
    return write_count;
}