pimoroni-pico/drivers/ltr559/ltr559.cpp

251 lines
7.6 KiB
C++

#include "ltr559.hpp"
#include <algorithm>
namespace pimoroni {
lookup::lookup(std::initializer_list<uint16_t> values) : lut(values) {
}
uint8_t lookup::index(uint16_t value) {
auto it = find(lut.begin(), lut.end(), value);
if(it == lut.end())
return 0;
return it - lut.begin();
}
uint16_t lookup::value(uint8_t index) {
return lut[index];
}
pimoroni::lookup LTR559::lookup_led_current({5, 10, 20, 50, 100});
pimoroni::lookup LTR559::lookup_led_duty_cycle({25, 50, 75, 100});
pimoroni::lookup LTR559::lookup_led_pulse_freq({30, 40, 50, 60, 70, 80, 90, 100});
pimoroni::lookup LTR559::lookup_proximity_meas_rate({10, 50, 70, 100, 200, 500, 1000, 2000});
pimoroni::lookup LTR559::lookup_light_integration_time({100, 50, 200, 400, 150, 250, 300, 350});
pimoroni::lookup LTR559::lookup_light_repeat_rate({50, 100, 200, 500, 1000, 2000});
pimoroni::lookup LTR559::lookup_light_gain({1, 2, 4, 8, 0, 0, 48, 96});
bool LTR559::init() {
if(interrupt != PIN_UNUSED) {
gpio_set_function(interrupt, GPIO_FUNC_SIO);
gpio_set_dir(interrupt, GPIO_IN);
gpio_pull_up(interrupt);
}
reset();
interrupts(true, true);
// 50mA, 100% duty cycle, 30Hz, 1 pulse
proximity_led(50, 100, 30, 1);
// enabled, gain 4x
light_control(true, 4);
// enabled, saturation indicator enabled
proximity_control(true, true);
// 100ms measurement rate
proximity_measurement_rate(100);
// 50ms integration time and repeat rate
light_measurement_rate(50, 50);
light_threshold(0xFFFF, 0x0000);
proximity_threshold(0x7FFF, 0x7FFF);
proximity_offset(0);
return true;
}
void LTR559::reset() {
i2c->set_bits(address, LTR559_ALS_CONTROL, LTR559_ALS_CONTROL_SW_RESET_BIT);
while(i2c->get_bits(address, LTR559_ALS_CONTROL, LTR559_ALS_CONTROL_SW_RESET_BIT)) {
sleep_ms(100);
}
}
i2c_inst_t* LTR559::get_i2c() const {
return i2c->get_i2c();
}
int LTR559::get_address() const {
return address;
}
int LTR559::get_sda() const {
return i2c->get_sda();
}
int LTR559::get_scl() const {
return i2c->get_sda();
}
int LTR559::get_int() const {
return interrupt;
}
uint8_t LTR559::part_id() {
uint8_t part_id;
i2c->read_bytes(address, LTR559_PART_ID, &part_id, 1);
return (part_id >> LTR559_PART_ID_PART_NUMBER_SHIFT) & LTR559_PART_ID_PART_NUMBER_MASK;
}
uint8_t LTR559::revision_id() {
uint8_t revision_id;
i2c->read_bytes(address, LTR559_PART_ID, &revision_id, 1);
return revision_id & LTR559_PART_ID_REVISION_MASK;
}
uint8_t LTR559::manufacturer_id() {
uint8_t manufacturer;
i2c->read_bytes(address, LTR559_MANUFACTURER_ID, &manufacturer, 1);
return manufacturer;
}
bool LTR559::get_reading() {
bool has_updated = false;
uint8_t status;
i2c->read_bytes(address, LTR559_ALS_PS_STATUS, &status, 1);
bool als_int = (status >> LTR559_ALS_PS_STATUS_ALS_INTERRUPT_BIT) & 0b1;
bool ps_int = (status >> LTR559_ALS_PS_STATUS_PS_INTERRUPT_BIT) & 0b1;
bool als_data = (status >> LTR559_ALS_PS_STATUS_ALS_DATA_BIT) & 0b1;
bool ps_data = (status >> LTR559_ALS_PS_STATUS_PS_DATA_BIT) & 0b1;
if(ps_int || ps_data) {
has_updated = true;
uint16_t ps0;
i2c->read_bytes(address, LTR559_PS_DATA, (uint8_t *)&ps0, 2);
ps0 &= LTR559_PS_DATA_MASK;
data.proximity = ps0;
}
if(als_int || als_data) {
has_updated = true;
uint16_t als[2];
i2c->read_bytes(address, LTR559_ALS_DATA_CH1, (uint8_t *)&als, 4);
data.als0 = als[1];
data.als1 = als[0];
data.gain = this->lookup_light_gain.value((status >> LTR559_ALS_PS_STATUS_ALS_GAIN_SHIFT) & LTR559_ALS_PS_STATUS_ALS_GAIN_MASK);
data.ratio = 101.0f;
if((uint32_t)data.als0 + data.als1 > 0) {
data.ratio = (float)data.als1 * 100.0f / ((float)data.als1 + data.als0);
}
uint8_t ch_idx = 3;
if(this->data.ratio < 45)
ch_idx = 0;
else if(data.ratio < 64)
ch_idx = 1;
else if (data.ratio < 85)
ch_idx = 2;
float lux = ((int32_t)data.als0 * ch0_c[ch_idx]) - ((int32_t)data.als1 * ch1_c[ch_idx]);
lux /= (float)this->data.integration_time / 100.0f;
lux /= (float)this->data.gain;
data.lux = lux / 10000.0f;
}
return has_updated;
}
void LTR559::interrupts(bool light, bool proximity) {
uint8_t buf = 0;
buf |= 0b1 << LTR559_INTERRUPT_POLARITY_BIT;
buf |= (uint8_t)light << LTR559_INTERRUPT_ALS_BIT;
buf |= (uint8_t)proximity << LTR559_INTERRUPT_PS_BIT;
i2c->write_bytes(address, LTR559_INTERRUPT, &buf, 1);
}
void LTR559::proximity_led(uint8_t current, uint8_t duty_cycle, uint8_t pulse_freq, uint8_t num_pulses) {
current = lookup_led_current.index(current);
duty_cycle = lookup_led_duty_cycle.index(duty_cycle);
duty_cycle <<= LTR559_PS_LED_DUTY_CYCLE_SHIFT;
pulse_freq = lookup_led_pulse_freq.index(pulse_freq);
pulse_freq <<= LTR559_PS_LED_PULSE_FREQ_SHIFT;
uint8_t buf = current | duty_cycle | pulse_freq;
i2c->write_bytes(address, LTR559_PS_LED, &buf, 1);
buf = num_pulses & LTR559_PS_N_PULSES_MASK;
i2c->write_bytes(address, LTR559_PS_N_PULSES, &buf, 1);
}
void LTR559::light_control(bool active, uint8_t gain) {
uint8_t buf = 0;
gain = lookup_light_gain.index(gain);
buf |= gain << LTR559_ALS_CONTROL_GAIN_SHIFT;
if(active)
buf |= (0b1 << LTR559_ALS_CONTROL_MODE_BIT);
else
buf &= ~(0b1 << LTR559_ALS_CONTROL_MODE_BIT);
i2c->write_bytes(address, LTR559_ALS_CONTROL, &buf, 1);
}
void LTR559::proximity_control(bool active, bool saturation_indicator) {
uint8_t buf = 0;
i2c->read_bytes(address, LTR559_PS_CONTROL, &buf, 1);
if(active)
buf |= LTR559_PS_CONTROL_ACTIVE_MASK;
else
buf &= ~LTR559_PS_CONTROL_ACTIVE_MASK;
if(saturation_indicator)
buf |= 0b1 << LTR559_PS_CONTROL_SATURATION_INDICATOR_ENABLE_BIT;
else
buf &= ~(0b1 << LTR559_PS_CONTROL_SATURATION_INDICATOR_ENABLE_BIT);
i2c->write_bytes(address, LTR559_PS_CONTROL, &buf, 1);
}
void LTR559::light_threshold(uint16_t lower, uint16_t upper) {
lower = __builtin_bswap16(lower);
upper = __builtin_bswap16(upper);
i2c->write_bytes(address, LTR559_ALS_THRESHOLD_LOWER, (uint8_t *)&lower, 2);
i2c->write_bytes(address, LTR559_ALS_THRESHOLD_UPPER, (uint8_t *)&upper, 2);
}
void LTR559::proximity_threshold(uint16_t lower, uint16_t upper) {
lower = uint16_to_bit12(lower);
upper = uint16_to_bit12(upper);
i2c->write_bytes(address, LTR559_PS_THRESHOLD_LOWER, (uint8_t *)&lower, 2);
i2c->write_bytes(address, LTR559_PS_THRESHOLD_UPPER, (uint8_t *)&upper, 2);
}
void LTR559::light_measurement_rate(uint16_t integration_time, uint16_t rate) {
data.integration_time = integration_time;
integration_time = lookup_light_integration_time.index(integration_time);
rate = lookup_light_repeat_rate.index(rate);
uint8_t buf = 0;
buf |= rate;
buf |= integration_time << LTR559_ALS_MEAS_RATE_INTEGRATION_TIME_SHIFT;
i2c->write_bytes(address, LTR559_ALS_MEAS_RATE, &buf, 1);
}
void LTR559::proximity_measurement_rate(uint16_t rate) {
uint8_t buf = lookup_proximity_meas_rate.index(rate);
i2c->write_bytes(address, LTR559_PS_MEAS_RATE, &buf, 1);
}
void LTR559::proximity_offset(uint16_t offset) {
offset &= LTR559_PS_OFFSET_MASK;
i2c->write_bytes(address, LTR559_PS_OFFSET, (uint8_t *)&offset, 1);
}
uint16_t LTR559::bit12_to_uint16(uint16_t value) {
return ((value & 0xFF00) >> 8) | ((value & 0x000F) << 8);
}
uint16_t LTR559::uint16_to_bit12(uint16_t value) {
return ((value & 0xFF) << 8) | ((value & 0xF00) >> 8);
}
}