28 lines
772 B
C++
28 lines
772 B
C++
#include "voltage.h"
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// Pin definitions
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static const int PIN_VBAT = A0;
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// Voltage divider constants
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// Divider: 100k upper (to Vin), 47k lower (to GND)
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// Vout = Vin * (47k / (100k + 47k)) = Vin * 0.3197
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// At 12V: ADC sees 3.84V | At 14.4V: ADC sees 4.60V
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static const float DIVIDER_RATIO = 47.0 / (100.0 + 47.0); // ~0.3197
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static const float ADC_REF = 5.0;
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static const int ADC_MAX = 1023;
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void voltage_init() {
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// analogRead doesn't need explicit pinMode, but here for future config
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// e.g., could switch to internal 1.1V reference for different range
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}
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int voltage_read_raw() {
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return analogRead(PIN_VBAT);
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}
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float voltage_read() {
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int raw = voltage_read_raw();
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float vDivider = (raw / (float)ADC_MAX) * ADC_REF;
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return vDivider / DIVIDER_RATIO;
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}
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