src/lib/THERMAL/lm75a.cpp

   1 #ifdef HAS_THERMAL_LM75A
   2 #include "lm75a.h"
   3 #include "logging.h"
   4
   5
   6 int LM75A::init()
   7 {
   8     uint8_t buffer[5];
   9
  10     ReadAccRegister(LM75A_REG_TOS, buffer, 2);
  11
  12     DBGLN("thermal lma75 read Tos = 0x%x", buffer[0]);
  13
  14     if(buffer[0] == 0)
  15     {
  16         ERRLN("thermal lma75 init failed!");
  17         return -1;
  18     }
  19
  20     return 0;
  21 }
  22
  23 uint8_t LM75A::read_lm75a()
  24 {
  25     uint8_t buffer[5];
  26     ReadAccRegister(LM75A_REG_TEMP, buffer, 2);
  27
  28     // ignore the second byte as it's the decimal part of a degree.
  29     return buffer[0];
  30 }
  31
  32 void LM75A::update_lm75a_threshold(uint8_t tos, uint8_t thyst)
  33 {
  34     uint8_t buffer[5];
  35     buffer[0] = thyst;
  36     buffer[1] = 0;
  37     WriteAccRegister(LM75A_REG_THYST, buffer, 2);
  38
  39     buffer[0] = tos;
  40     buffer[1] = 0;
  41     WriteAccRegister(LM75A_REG_TOS, buffer, 2);
  42 }
  43
  44 void LM75A::ReadAccRegister(uint8_t reg, uint8_t *data, int size)
  45 {
  46     Wire.beginTransmission(LM75A_I2C_ADDRESS);
  47     Wire.write(reg);
  48     Wire.endTransmission();
  49
  50     Wire.requestFrom(LM75A_I2C_ADDRESS, size);    // request 1 bytes from slave device
  51     Wire.readBytes(data, size);
  52 }
  53
  54 void LM75A::WriteAccRegister(uint8_t reg, uint8_t *data, int size)
  55 {
  56     Wire.beginTransmission(LM75A_I2C_ADDRESS);
  57     Wire.write(reg);
  58     Wire.write(data, size);
  59     Wire.endTransmission();
  60 }
  61 #endif