34 lines
985 B
C++
34 lines
985 B
C++
/**
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* @author Matthew Kennedy, (c) 2019
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*/
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#include "resistance_func.h"
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#include "loggingcentral.h"
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void ResistanceFunc::configure(float supplyVoltage, float pullupResistor) {
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m_pullupResistor = pullupResistor;
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m_supplyVoltage = supplyVoltage;
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}
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SensorResult ResistanceFunc::convert(float raw) const {
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// If the voltage is very low, the sensor is a dead short.
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if (raw < 0.05f) {
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return {false, 0.0f};
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}
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// If the voltage is very high (98% VCC), the sensor is open circuit.
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if (raw > (m_supplyVoltage * 0.98f)) {
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return {false, 1e6};
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}
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// Voltage is in a sensible range - convert
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float resistance = m_pullupResistor / (m_supplyVoltage / raw - 1);
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return {true, resistance};
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}
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void ResistanceFunc::showInfo(Logging* logger, float testInputValue) const {
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const auto result = convert(testInputValue);
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scheduleMsg(logger, " %.2f volts -> %.1f ohms with supply voltage %.2f and pullup %.1f.", testInputValue, result.Value, m_supplyVoltage, m_pullupResistor);
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}
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