ina219.setCalibration_16V_400mA();

#include <Adafruit_INA219.h>
#include <Adafruit_GFX.h>
#include <Adafruit_ST7735.h>
#include <SPI.h>

#define TFT_CS    1
#define TFT_RST   2
#define TFT_DC    3
#define TFT_SCLK  8
#define TFT_MOSI 10

#define BLACK   ST7735_WHITE
#define CYAN    ST7735_BLUE
#define ORANGE  ST7735_ORANGE

Adafruit_INA219 ina219;
Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_MOSI,
TFT_SCLK, TFT_RST);

void setup() {

  tft.initR(INITR_MINI160x80);
  tft.setTextWrap(false);
  tft.setRotation(1);
  tft.setTextSize(1);
  tft.setTextColor(ORANGE);

  if (! ina219.begin()) {
    while (1) {
      tft.setCursor(5, 30);
      tft.print("Failed to find INA219 chip");
      delay(10);
    }
  }
  ina219.setCalibration_16V_400mA();
}

void loop() {

  float shuntvoltage = ina219.getShuntVoltage_mV();
  float busvoltage   = ina219.getBusVoltage_V();
  float current_mA   = ina219.getCurrent_mA();
  float power_mW     = ina219.getPower_mW();
  float loadvoltage  = busvoltage + (shuntvoltage / 1000);

  tft.fillScreen(BLACK);

  tft.setTextSize(2);
  tft.setTextColor(ORANGE);

  tft.setCursor(5, 5);
  tft.print("bus:");
  tft.print(busvoltage);
  tft.print("V");

  // tft.print("loadV:");
  // tft.print(loadvoltage);

  tft.setCursor(5, 23);
  tft.print("shunt:");
  tft.print(shuntvoltage);
  tft.print("mV");

  tft.setCursor(5, 41);
  tft.setTextColor(CYAN);
  tft.print("cur.:");
  tft.print(current_mA,1);
  tft.print("mA");

  tft.setCursor(5, 59);
  tft.print("power:");
  tft.print(power_mW,1);
  tft.print("mW");

  delay(1000);
}