OneWire.h

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#ifndef OneWire_h
#define OneWire_h

#include <inttypes.h>

#if ARDUINO >= 100
#include "Arduino.h" // for delayMicroseconds, digitalPinToBitMask, etc
#else
#include "WProgram.h"     // for delayMicroseconds
#include "pins_arduino.h" // for digitalPinToBitMask, etc
#endif

// You can exclude certain features from OneWire.  In theory, this
// might save some space.  In practice, the compiler automatically
// removes unused code (technically, the linker, using -fdata-sections
// and -ffunction-sections when compiling, and Wl,--gc-sections
// when linking), so most of these will not result in any code size
// reduction.  Well, unless you try to use the missing features
// and redesign your program to not need them!  ONEWIRE_CRC8_TABLE
// is the exception, because it selects a fast but large algorithm
// or a small but slow algorithm.

// you can exclude onewire_search by defining that to 0
#ifndef ONEWIRE_SEARCH
#define ONEWIRE_SEARCH 1 
#endif

// You can exclude CRC checks altogether by defining this to 0
#ifndef ONEWIRE_CRC
#define ONEWIRE_CRC 1 
#endif

// Select the table-lookup method of computing the 8-bit CRC
// by setting this to 1.  The lookup table enlarges code size by
// about 250 bytes.  It does NOT consume RAM (but did in very
// old versions of OneWire).  If you disable this, a slower
// but very compact algorithm is used.
#ifndef ONEWIRE_CRC8_TABLE
#define ONEWIRE_CRC8_TABLE                                                     \
  1 
#endif

// You can allow 16-bit CRC checks by defining this to 1
// (Note that ONEWIRE_CRC must also be 1.)
#ifndef ONEWIRE_CRC16
#define ONEWIRE_CRC16                                                          \
  1 
#endif

#define FALSE 0 
#define TRUE 1  

// Platform specific I/O definitions

#if defined(__AVR__)
#define PIN_TO_BASEREG(pin) (portInputRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint8_t
#define IO_REG_ASM asm("r30")
#define DIRECT_READ(base, mask) (((*(base)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) ((*((base) + 1)) &= ~(mask))
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base) + 1)) |= (mask))
#define DIRECT_WRITE_LOW(base, mask) ((*((base) + 2)) &= ~(mask))
#define DIRECT_WRITE_HIGH(base, mask) ((*((base) + 2)) |= (mask))

#elif defined(__MK20DX128__)
#define PIN_TO_BASEREG(pin) (portOutputRegister(pin))
#define PIN_TO_BITMASK(pin) (1)
#define IO_REG_TYPE uint8_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask) (*((base) + 512))
#define DIRECT_MODE_INPUT(base, mask) (*((base) + 640) = 0)
#define DIRECT_MODE_OUTPUT(base, mask) (*((base) + 640) = 1)
#define DIRECT_WRITE_LOW(base, mask) (*((base) + 256) = 1)
#define DIRECT_WRITE_HIGH(base, mask) (*((base) + 128) = 1)

#elif defined(__SAM3X8E__)
// Arduino 1.5.1 may have a bug in delayMicroseconds() on Arduino Due.
// http://arduino.cc/forum/index.php/topic,141030.msg1076268.html#msg1076268
// If you have trouble with OneWire on Arduino Due, please check the
// status of delayMicroseconds() before reporting a bug in OneWire!
#define PIN_TO_BASEREG(pin) (&(digitalPinToPort(pin)->PIO_PER))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask) (((*((base) + 15)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) ((*((base) + 5)) = (mask))
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base) + 4)) = (mask))
#define DIRECT_WRITE_LOW(base, mask) ((*((base) + 13)) = (mask))
#define DIRECT_WRITE_HIGH(base, mask) ((*((base) + 12)) = (mask))
#ifndef PROGMEM
#define PROGMEM
#endif
#ifndef pgm_read_byte
#define pgm_read_byte(addr) (*(const uint8_t *)(addr))
#endif

#elif defined(__PIC32MX__)
#define PIN_TO_BASEREG(pin) (portModeRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask)                                                \
  (((*(base + 4)) & (mask)) ? 1 : 0) // PORTX + 0x10
#define DIRECT_MODE_INPUT(base, mask)                                          \
  ((*(base + 2)) = (mask)) // TRISXSET +
                           // 0x08
#define DIRECT_MODE_OUTPUT(base, mask)                                         \
  ((*(base + 1)) = (mask)) // TRISXCLR + 0x04
#define DIRECT_WRITE_LOW(base, mask)                                           \
  ((*(base + 8 + 1)) = (mask)) // LATXCLR  + 0x24
#define DIRECT_WRITE_HIGH(base, mask)                                          \
  ((*(base + 8 + 2)) = (mask)) // LATXSET + 0x28

#elif defined(ARDUINO_ARCH_ESP8266)
#define PIN_TO_BASEREG(pin) ((volatile uint32_t *)GPO)
#define PIN_TO_BITMASK(pin) (1 << pin)
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask) ((GPI & (mask)) ? 1 : 0) // GPIO_IN_ADDRESS
#define DIRECT_MODE_INPUT(base, mask)                                          \
  (GPE &= ~(mask)) // GPIO_ENABLE_W1TC_ADDRESS
#define DIRECT_MODE_OUTPUT(base, mask)                                         \
  (GPE |= (mask))                                    // GPIO_ENABLE_W1TS_ADDRESS
#define DIRECT_WRITE_LOW(base, mask) (GPOC = (mask)) // GPIO_OUT_W1TC_ADDRESS
#define DIRECT_WRITE_HIGH(base, mask) (GPOS = (mask)) // GPIO_OUT_W1TS_ADDRESS

#elif defined(__SAMD21G18A__) || defined(__SAMD21E18A__)
#define PIN_TO_BASEREG(pin) portModeRegister(digitalPinToPort(pin))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask) (((*((base) + 8)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask) ((*((base) + 1)) = (mask))
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base) + 2)) = (mask))
#define DIRECT_WRITE_LOW(base, mask) ((*((base) + 5)) = (mask))
#define DIRECT_WRITE_HIGH(base, mask) ((*((base) + 6)) = (mask))

#elif defined(__SAMD51__)
#define PIN_TO_BASEREG(pin) portModeRegister(digitalPinToPort(pin))
#define PIN_TO_BITMASK(pin) (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask) (((*((base) + 8)) & (mask)) ? 1 : 0) // IN
#define DIRECT_MODE_INPUT(base, mask) ((*((base) + 1)) = (mask))     // DIRCLR
#define DIRECT_MODE_OUTPUT(base, mask) ((*((base) + 2)) = (mask))    // DIRSET
#define DIRECT_WRITE_LOW(base, mask) ((*((base) + 5)) = (mask))      // OUTCLR
#define DIRECT_WRITE_HIGH(base, mask) ((*((base) + 6)) = (mask))     

#elif defined(ARDUINO_NRF52_ADAFRUIT)
#define PIN_TO_BASEREG(pin) (0)
#define PIN_TO_BITMASK(pin) digitalPinToPinName(pin)
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, pin) nrf_gpio_pin_read(pin)
#define DIRECT_WRITE_LOW(base, pin) nrf_gpio_pin_clear(pin)
#define DIRECT_WRITE_HIGH(base, pin) nrf_gpio_pin_set(pin)
#define DIRECT_MODE_INPUT(base, pin)                                           \
  nrf_gpio_cfg_input(pin, NRF_GPIO_PIN_NOPULL)
#define DIRECT_MODE_OUTPUT(base, pin) nrf_gpio_cfg_output(pin)

#else
#error "Please define I/O register types here"
#endif

class OneWire {
private:
  IO_REG_TYPE bitmask;
  volatile IO_REG_TYPE *baseReg;

#if ONEWIRE_SEARCH
  // global search state
  unsigned char ROM_NO[8];
  uint8_t LastDiscrepancy;
  uint8_t LastFamilyDiscrepancy;
  uint8_t LastDeviceFlag;
#endif

public:
  OneWire(uint8_t pin);

  uint8_t reset(void);

  void select(const uint8_t rom[8]);

  void skip(void);

  void write(uint8_t v, uint8_t power = 0);

  void write_bytes(const uint8_t *buf, uint16_t count, bool power = 0);

  uint8_t read(void);

  void read_bytes(uint8_t *buf, uint16_t count);

  void write_bit(uint8_t v);

  uint8_t read_bit(void);

  void depower(void);

#if ONEWIRE_SEARCH

  void reset_search();

  void target_search(uint8_t family_code);

  uint8_t search(uint8_t *newAddr);
#endif

#if ONEWIRE_CRC

  static uint8_t crc8(const uint8_t *addr, uint8_t len);

#if ONEWIRE_CRC16

  static bool check_crc16(const uint8_t *input, uint16_t len,
                          const uint8_t *inverted_crc, uint16_t crc = 0);

  static uint16_t crc16(const uint8_t *input, uint16_t len, uint16_t crc = 0);
#endif
#endif
};

#endif