Merge pull request #483 from Riksu9000/fix_adc

Fix misconfigured ADC and remove now unnecessary filtering
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JF002 2021-08-10 12:32:09 +02:00 committed by GitHub
commit 9fb3755088
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2 changed files with 16 additions and 57 deletions

View file

@ -23,7 +23,6 @@ void Battery::Update() {
return; return;
} }
// Non blocking read // Non blocking read
samples = 0;
isReading = true; isReading = true;
SaadcInit(); SaadcInit();
@ -40,9 +39,9 @@ void Battery::SaadcInit() {
nrf_saadc_channel_config_t adcChannelConfig = {.resistor_p = NRF_SAADC_RESISTOR_DISABLED, nrf_saadc_channel_config_t adcChannelConfig = {.resistor_p = NRF_SAADC_RESISTOR_DISABLED,
.resistor_n = NRF_SAADC_RESISTOR_DISABLED, .resistor_n = NRF_SAADC_RESISTOR_DISABLED,
.gain = NRF_SAADC_GAIN1_5, .gain = NRF_SAADC_GAIN1_4,
.reference = NRF_SAADC_REFERENCE_INTERNAL, .reference = NRF_SAADC_REFERENCE_INTERNAL,
.acq_time = NRF_SAADC_ACQTIME_3US, .acq_time = NRF_SAADC_ACQTIME_40US,
.mode = NRF_SAADC_MODE_SINGLE_ENDED, .mode = NRF_SAADC_MODE_SINGLE_ENDED,
.burst = NRF_SAADC_BURST_ENABLED, .burst = NRF_SAADC_BURST_ENABLED,
.pin_p = batteryVoltageAdcInput, .pin_p = batteryVoltageAdcInput,
@ -60,22 +59,21 @@ void Battery::SaadcEventHandler(nrfx_saadc_evt_t const* p_event) {
APP_ERROR_CHECK(nrfx_saadc_buffer_convert(&saadc_value, 1)); APP_ERROR_CHECK(nrfx_saadc_buffer_convert(&saadc_value, 1));
// A hardware voltage divider divides the battery voltage by 2 // A hardware voltage divider divides the battery voltage by 2
// ADC gain is 1/5 // ADC gain is 1/4
// thus adc_voltage = battery_voltage / 2 * gain = battery_voltage / 10 // thus adc_voltage = battery_voltage / 2 * gain = battery_voltage / 8
// reference_voltage is 0.6V // reference_voltage is 600mV
// p_event->data.done.p_buffer[0] = (adc_voltage / reference_voltage) * 1024 // p_event->data.done.p_buffer[0] = (adc_voltage / reference_voltage) * 1024
voltage = p_event->data.done.p_buffer[0] * 6000 / 1024; voltage = p_event->data.done.p_buffer[0] * (8 * 600) / 1024;
percentRemaining = (voltage - battery_min) * 100 / (battery_max - battery_min);
percentRemaining = std::max(percentRemaining, 0);
percentRemaining = std::min(percentRemaining, 100);
percentRemainingBuffer.Insert(percentRemaining);
samples++; if (voltage > battery_max) {
if (samples > percentRemainingSamples) { percentRemaining = 100;
nrfx_saadc_uninit(); } else if (voltage < battery_min) {
isReading = false; percentRemaining = 0;
} else { } else {
nrfx_saadc_sample(); percentRemaining = (voltage - battery_min) * 100 / (battery_max - battery_min);
} }
nrfx_saadc_uninit();
isReading = false;
} }
} }

View file

@ -7,38 +7,6 @@
namespace Pinetime { namespace Pinetime {
namespace Controllers { namespace Controllers {
/** A simple circular buffer that can be used to average
out the sensor values. The total capacity of the CircBuffer
is given as the template parameter N.
*/
template <int N> class CircBuffer {
public:
CircBuffer() : arr {}, sz {}, cap {N}, head {} {
}
/**
insert member function overwrites the next data to the current
HEAD and moves the HEAD to the newly inserted value.
*/
void Insert(const uint8_t num) {
head %= cap;
arr[head++] = num;
if (sz != cap) {
sz++;
}
}
uint8_t GetAverage() const {
int sum = std::accumulate(arr.begin(), arr.end(), 0);
return static_cast<uint8_t>(sum / sz);
}
private:
std::array<uint8_t, N> arr; /**< internal array used to store the values*/
uint8_t sz; /**< The current size of the array.*/
uint8_t cap; /**< Total capacity of the CircBuffer.*/
uint8_t head; /**< The current head of the CircBuffer*/
};
class Battery { class Battery {
public: public:
Battery(); Battery();
@ -47,10 +15,7 @@ namespace Pinetime {
void Update(); void Update();
uint8_t PercentRemaining() const { uint8_t PercentRemaining() const {
auto avg = percentRemainingBuffer.GetAverage(); return percentRemaining;
avg = std::min(avg, static_cast<uint8_t>(100));
avg = std::max(avg, static_cast<uint8_t>(0));
return avg;
} }
uint16_t Voltage() const { uint16_t Voltage() const {
@ -69,14 +34,11 @@ namespace Pinetime {
static Battery* instance; static Battery* instance;
nrf_saadc_value_t saadc_value; nrf_saadc_value_t saadc_value;
static constexpr uint8_t percentRemainingSamples = 5;
CircBuffer<percentRemainingSamples> percentRemainingBuffer {};
static constexpr uint32_t chargingPin = 12; static constexpr uint32_t chargingPin = 12;
static constexpr uint32_t powerPresentPin = 19; static constexpr uint32_t powerPresentPin = 19;
static constexpr nrf_saadc_input_t batteryVoltageAdcInput = NRF_SAADC_INPUT_AIN7; static constexpr nrf_saadc_input_t batteryVoltageAdcInput = NRF_SAADC_INPUT_AIN7;
uint16_t voltage = 0; uint16_t voltage = 0;
int percentRemaining = -1; uint8_t percentRemaining = 0;
bool isCharging = false; bool isCharging = false;
bool isPowerPresent = false; bool isPowerPresent = false;
@ -87,7 +49,6 @@ namespace Pinetime {
static void AdcCallbackStatic(nrfx_saadc_evt_t const* event); static void AdcCallbackStatic(nrfx_saadc_evt_t const* event);
bool isReading = false; bool isReading = false;
uint8_t samples = 0;
}; };
} }
} }