初始化提交

arduino-cli/libraries/LM75A/LM75A.cpp

@@ -0,0 +1,114 @@
+/*
+ * \brief I2C LM75A temperature sensor library (implementation)
+ *
+ * \author Quentin Comte-Gaz <quentin@comte-gaz.com>
+ * \date 8 July 2016 & 14 January 2018
+ * \license MIT License (contact me if too restrictive)
+ * \copyright Copyright (c) 2016 Quentin Comte-Gaz
+ * \version 1.1
+ */
+
+#include "LM75A.h"
+#include <Wire.h>
+
+namespace LM75AConstValues
+{
+
+const int LM75A_BASE_ADDRESS = 0x48;
+
+const float LM75A_DEGREES_RESOLUTION = 0.125;
+
+const int LM75A_REG_ADDR_TEMP = 0;
+//const int LM75A_REG_ADDR_CONF = 1;  // Not used for now
+//const int LM57A_REG_ADDR_THYST = 2; // Not used for now
+//const int LM57A_REG_ADDR_TOS = 3;   // Not used for now
+
+}
+
+using namespace LM75AConstValues;
+
+LM75A::LM75A(bool A0_value, bool A1_value, bool A2_value)
+{
+  _i2c_device_address = LM75A_BASE_ADDRESS;
+
+  if (A0_value) {
+    _i2c_device_address += 1;
+  }
+
+  if (A1_value) {
+    _i2c_device_address += 2;
+  }
+
+  if (A2_value) {
+    _i2c_device_address += 4;
+  }
+
+  Wire.begin();
+}
+
+float LM75A::fahrenheitToDegrees(float temperature_in_fahrenheit)
+{
+  return ((temperature_in_fahrenheit - 32.0) / 1.8);
+}
+
+float LM75A::degreesToFahrenheit(float temperature_in_degrees)
+{
+  return ((temperature_in_degrees * 1.8) + 32.0);
+}
+
+float LM75A::getTemperatureInFahrenheit() const
+{
+  float temperature_in_degrees = getTemperatureInDegrees();
+
+  if (temperature_in_degrees == INVALID_LM75A_TEMPERATURE) {
+    return INVALID_LM75A_TEMPERATURE;
+  }
+
+  return degreesToFahrenheit(temperature_in_degrees);
+}
+
+float LM75A::getTemperatureInDegrees() const
+{
+  uint16_t real_result = INVALID_LM75A_TEMPERATURE;
+  uint16_t i2c_received = 0;
+
+  // Go to temperature data register
+  Wire.beginTransmission(_i2c_device_address);
+  Wire.write(LM75A_REG_ADDR_TEMP);
+  if(Wire.endTransmission()) {
+    // Transmission error
+    return real_result;
+  }
+
+  // Get content
+  if (Wire.requestFrom(_i2c_device_address, 2)) {
+    Wire.readBytes((uint8_t*)&i2c_received, 2);
+  } else {
+    // Can't read temperature
+    return real_result;
+  }
+
+  // Modify the value (only 11 MSB are relevant if swapped)
+  int16_t refactored_value;
+  uint8_t* ptr = (uint8_t*)&refactored_value;
+
+  // Swap bytes
+  *ptr = *((uint8_t*)&i2c_received + 1);
+  *(ptr + 1) = *(uint8_t*)&i2c_received;
+
+  // Shift data (left-aligned)
+  refactored_value >>= 5;
+
+  float real_value;
+  if (refactored_value & 0x0400) {
+    // When sign bit is set, set upper unused bits, then 2's complement
+    refactored_value |= 0xf800;
+    refactored_value = ~refactored_value + 1;
+    real_value = (float)refactored_value * (-1) * LM75A_DEGREES_RESOLUTION;
+  }
+  else {
+    real_value = (float)refactored_value *  LM75A_DEGREES_RESOLUTION;
+  }
+
+  return real_value;
+}