int TSL2561_OPEN(TSL2561 *sensor) {
char filename[20];
if(sensor->adapter_fd != -1) { // already opened
// TODO: choose a valid errno error
sensor->lasterr = -1;
return -1;
}
snprintf(filename, 20, "/dev/i2c-%d", sensor->adapter_nr);
if ((sensor->adapter_fd = open(filename, O_RDWR)) < 0) { // open the device file (requests i2c-dev kernel module loaded)
sensor->lasterr = errno;
return -1;
}
if (ioctl(sensor->adapter_fd, I2C_SLAVE, sensor->sensor_addr) < 0) { // talk to the requested device
sensor->lasterr = errno;
close(sensor->adapter_fd);
sensor->adapter_fd = -1;
return -1;
}
TSL2561_SETINTEGRATIONTIME(sensor, TSL2561_INTEGRATIONTIME_402MS);
TSL2561_SETGAIN(sensor, TSL2561_GAIN_16X);
/*
TSL2561_ON(sensor);
tsl2561_write8(sensor, 0x81, 0x11);
TSL2561_OFF(sensor);
*/
return 0;
}
int main() {
int rc;
uint16_t broadband, ir;
uint32_t lux=0;
// prepare the sensor
// (the first parameter is the raspberry pi i2c master controller attached to the TSL2561, the second is the i2c selection jumper)
// The i2c selection address can be one of: TSL2561_ADDR_LOW, TSL2561_ADDR_FLOAT or TSL2561_ADDR_HIGH
TSL2561 light1 = TSL2561_INIT(1, TSL2561_ADDR_FLOAT);
// initialize the sensor
rc = TSL2561_OPEN(&light1);
if(rc != 0) {
fprintf(stderr, "Error initializing TSL2561 sensor (%s). Check your i2c bus (es. i2cdetect)\n", strerror(light1.lasterr));
// you don't need to TSL2561_CLOSE() if TSL2561_OPEN() failed, but it's safe doing it.
TSL2561_CLOSE(&light1);
return 1;
}
// set the gain to 1X (it can be TSL2561_GAIN_1X or TSL2561_GAIN_16X)
// use 16X gain to get more precision in dark ambients, or enable auto gain below
rc = TSL2561_SETGAIN(&light1, TSL2561_GAIN_1X);
// set the integration time
// (TSL2561_INTEGRATIONTIME_402MS or TSL2561_INTEGRATIONTIME_101MS or TSL2561_INTEGRATIONTIME_13MS)
// TSL2561_INTEGRATIONTIME_402MS is slower but more precise, TSL2561_INTEGRATIONTIME_13MS is very fast but not so precise
rc = TSL2561_SETINTEGRATIONTIME(&light1, TSL2561_INTEGRATIONTIME_101MS);
// sense the luminosity from the sensor (lux is the luminosity taken in "lux" measure units)
// the last parameter can be 1 to enable library auto gain, or 0 to disable it
rc = TSL2561_SENSELIGHT(&light1, &broadband, &ir, &lux, 1);
printf("Test. RC: %i(%s), broadband: %i, ir: %i, lux: %i\n", rc, strerror(light1.lasterr), broadband, ir, lux);
TSL2561_CLOSE(&light1);
return 0;
}
