Adafruit_MAX31865.h

00001 /*************************************************** 
00002   This is a library for the Adafruit PT100/P1000 RTD Sensor w/MAX31865
00003 
00004   Designed specifically to work with the Adafruit RTD Sensor
00005   ----> https://www.adafruit.com/products/3328
00006 
00007   This sensor uses SPI to communicate, 4 pins are required to  
00008   interface
00009   Adafruit invests time and resources providing this open source code, 
00010   please support Adafruit and open-source hardware by purchasing 
00011   products from Adafruit!
00012 
00013   Written by Limor Fried/Ladyada for Adafruit Industries.  
00014   BSD license, all text above must be included in any redistribution
00015   
00016   Modified for mbed project - Dan Julio - 5/2017
00017  ****************************************************/
00018 #ifndef ADAFRUIT_MAX31865_H
00019 #define ADAFRUIT_MAX31865_H
00020 
00021 #include <stdint.h>
00022 #include "mbed.h"
00023 #include "swspi.h"
00024 
00025 #define MAX31865_CONFIG_REG            0x00
00026 #define MAX31865_CONFIG_BIAS           0x80
00027 #define MAX31865_CONFIG_MODEAUTO       0x40
00028 #define MAX31865_CONFIG_MODEOFF        0x00
00029 #define MAX31865_CONFIG_1SHOT          0x20
00030 #define MAX31865_CONFIG_3WIRE          0x10
00031 #define MAX31865_CONFIG_24WIRE         0x00
00032 #define MAX31865_CONFIG_FAULTSTAT      0x02
00033 #define MAX31865_CONFIG_FILT50HZ       0x01
00034 #define MAX31865_CONFIG_FILT60HZ       0x00
00035 
00036 #define MAX31865_RTDMSB_REG           0x01
00037 #define MAX31865_RTDLSB_REG           0x02
00038 #define MAX31865_HFAULTMSB_REG        0x03
00039 #define MAX31865_HFAULTLSB_REG        0x04
00040 #define MAX31865_LFAULTMSB_REG        0x05
00041 #define MAX31865_LFAULTLSB_REG        0x06
00042 #define MAX31865_FAULTSTAT_REG        0x07
00043 
00044 
00045 #define MAX31865_FAULT_HIGHTHRESH     0x80
00046 #define MAX31865_FAULT_LOWTHRESH      0x40
00047 #define MAX31865_FAULT_REFINLOW       0x20
00048 #define MAX31865_FAULT_REFINHIGH      0x10
00049 #define MAX31865_FAULT_RTDINLOW       0x08
00050 #define MAX31865_FAULT_OVUV           0x04
00051 
00052 
00053 #define RTD_A 3.9083e-3
00054 #define RTD_B -5.775e-7
00055 
00056 typedef enum max31865_numwires { 
00057   MAX31865_2WIRE = 0,
00058   MAX31865_3WIRE = 1,
00059   MAX31865_4WIRE = 0
00060 } max31865_numwires_t;
00061 
00062 
00063 class Adafruit_MAX31865 {
00064  public:
00065   Adafruit_MAX31865(swspi& spiO, int ssNum, PinName rdyPin);
00066 
00067   bool begin(max31865_numwires_t x = MAX31865_2WIRE);
00068 
00069   uint8_t readFault(void);
00070   void clearFault(void);
00071   uint16_t readRTD();
00072 
00073   void setWires(max31865_numwires_t wires);
00074   void autoConvert(bool b);
00075   void enableBias(bool b);
00076   bool isReady(uint16_t* rtdVal);
00077   float temperature(float RTDnominal, float refResistor, uint16_t rtdVal = 0);
00078 
00079  private:
00080   bool                debug;
00081   int                 ssN;             // Slave select for swspi
00082   swspi&              spi;
00083   DigitalIn*          rdyP;     // Ready Pin
00084   
00085   void readRegisterN(uint8_t addr, uint8_t buffer[], uint8_t n);
00086 
00087   uint8_t  readRegister8(uint8_t addr);
00088   uint16_t readRegister16(uint8_t addr);
00089 
00090   void     writeRegister8(uint8_t addr, uint8_t reg);
00091 };
00092 
00093 
00094 #endif