// ============================================================
//  sketch.ino  —  Test INA226 Custom Chip Wokwi
//  Membaca: Shunt Voltage, Bus Voltage, Current, Power
// ============================================================
#include <Wire.h>

// ─── Konstanta INA226 ──────────────────────────────────────
#define INA226_ADDR       0x40

#define REG_CONFIG        0x00
#define REG_SHUNT_VOLTAGE 0x01
#define REG_BUS_VOLTAGE   0x02
#define REG_POWER         0x03
#define REG_CURRENT       0x04
#define REG_CALIBRATION   0x05
#define REG_MASK_ENABLE   0x06
#define REG_MANUFACTURER  0xFE
#define REG_DIE_ID        0xFF

// ─── Kalibrasi ─────────────────────────────────────────────
// R_shunt = 0.1 Ω, I_max = 1 A
// current_lsb = I_max / 32768 = 30.518 µA
// CAL = 0.00512 / (current_lsb × R_shunt)
//     = 0.00512 / (30.518e-6 × 0.1)
//     = 1677  → gunakan 1677 atau 2048 (lebih mudah hitung)
#define CAL_VALUE         1677

// ─── LSB per bit ───────────────────────────────────────────
#define SHUNT_LSB_UV      2.5f        // µV per bit (signed)
#define BUS_LSB_MV        1.25f       // mV per bit
#define CURRENT_LSB_uA    30.518f     // µA per bit
#define POWER_LSB_uW      (25.0f * CURRENT_LSB_uA)  // µW per bit

// ──────────────────────────────────────────────────────────
uint16_t readReg16(uint8_t reg) {
  Wire.beginTransmission(INA226_ADDR);
  Wire.write(reg);
  Wire.endTransmission(false);      // repeated START
  Wire.requestFrom(INA226_ADDR, 2);
  uint8_t msb = Wire.read();
  uint8_t lsb = Wire.read();
  return (uint16_t)((msb << 8) | lsb);
}

void writeReg16(uint8_t reg, uint16_t val) {
  Wire.beginTransmission(INA226_ADDR);
  Wire.write(reg);
  Wire.write((val >> 8) & 0xFF);    // MSB dulu
  Wire.write(val & 0xFF);           // LSB
  Wire.endTransmission();
}

// ──────────────────────────────────────────────────────────
void setup() {
  Serial.begin(115200);
  Wire.begin();
  delay(300);

  Serial.println(F("\n╔═══════════════════════════════╗"));
  Serial.println(F("║  INA226 Custom Chip - Wokwi  ║"));
  Serial.println(F("╚═══════════════════════════════╝"));

  // Verifikasi chip
  uint16_t mfg = readReg16(REG_MANUFACTURER);
  uint16_t die = readReg16(REG_DIE_ID);
  Serial.print(F("Manufacturer ID : 0x")); Serial.print(mfg, HEX);
  Serial.println(mfg == 0x5449 ? F("  ✓ (TI)") : F("  ✗ ERROR!"));
  Serial.print(F("Die ID          : 0x")); Serial.print(die, HEX);
  Serial.println(die == 0x2260 ? F("  ✓ (INA226)") : F("  ✗ ERROR!"));

  // Konfigurasi: AVG=16 avg, VBUSCT=1.1ms, VSHCT=1.1ms, continuous
  writeReg16(REG_CONFIG, 0x4527);
  Serial.println(F("Config          : 0x4527 (AVG=16, continuous)"));

  // Set kalibrasi
  writeReg16(REG_CALIBRATION, CAL_VALUE);
  Serial.print(F("Calibration     : ")); Serial.println(CAL_VALUE);

  Serial.println(F("───────────────────────────────────────────────"));
  Serial.println(F("  Shunt(mV)  Bus(V)   Current(mA)  Power(mW)  "));
  Serial.println(F("───────────────────────────────────────────────"));
}

void loop() {
  // Baca semua register pengukuran
  int16_t  raw_shunt = (int16_t)readReg16(REG_SHUNT_VOLTAGE);
  uint16_t raw_bus   = readReg16(REG_BUS_VOLTAGE);
  uint16_t raw_power = readReg16(REG_POWER);
  int16_t  raw_curr  = (int16_t)readReg16(REG_CURRENT);

  // Konversi ke satuan nyata
  float shunt_mV  = raw_shunt * SHUNT_LSB_UV   / 1000.0f;
  float bus_V     = raw_bus   * BUS_LSB_MV     / 1000.0f;
  float curr_mA   = raw_curr  * CURRENT_LSB_uA / 1000.0f;
  float power_mW  = raw_power * POWER_LSB_uW   / 1000.0f;

  // Tampilkan hasil
  char buf[60];
  snprintf(buf, sizeof(buf),
           "  %+8.3f   %6.3f   %+10.3f   %8.3f",
           shunt_mV, bus_V, curr_mA, power_mW);
  Serial.println(buf);

  // Tampilkan raw juga (sekali tiap 5 detik)
  static uint32_t last_raw = 0;
  if (millis() - last_raw > 5000) {
    last_raw = millis();
    Serial.println();
    Serial.print(F("[RAW] Shunt=")); Serial.print(raw_shunt);
    Serial.print(F(", Bus="));       Serial.print(raw_bus);
    Serial.print(F(", Curr="));      Serial.print(raw_curr);
    Serial.print(F(", Pwr="));       Serial.println(raw_power);
    Serial.println();
  }

  delay(1000);
}