--- /dev/null
+/*
+Copyright (c) 2007, Jim Studt (original old version - many contributors since)
+
+The latest version of this library may be found at:
+ http://www.pjrc.com/teensy/td_libs_OneWire.html
+
+OneWire has been maintained by Paul Stoffregen (paul@pjrc.com) since
+January 2010. At the time, it was in need of many bug fixes, but had
+been abandoned the original author (Jim Studt). None of the known
+contributors were interested in maintaining OneWire. Paul typically
+works on OneWire every 6 to 12 months. Patches usually wait that
+long. If anyone is interested in more actively maintaining OneWire,
+please contact Paul.
+
+Version 2.2:
+ Teensy 3.0 compatibility, Paul Stoffregen, paul@pjrc.com
+ Arduino Due compatibility, http://arduino.cc/forum/index.php?topic=141030
+ Fix DS18B20 example negative temperature
+ Fix DS18B20 example's low res modes, Ken Butcher
+ Improve reset timing, Mark Tillotson
+ Add const qualifiers, Bertrik Sikken
+ Add initial value input to crc16, Bertrik Sikken
+ Add target_search() function, Scott Roberts
+
+Version 2.1:
+ Arduino 1.0 compatibility, Paul Stoffregen
+ Improve temperature example, Paul Stoffregen
+ DS250x_PROM example, Guillermo Lovato
+ PIC32 (chipKit) compatibility, Jason Dangel, dangel.jason AT gmail.com
+ Improvements from Glenn Trewitt:
+ - crc16() now works
+ - check_crc16() does all of calculation/checking work.
+ - Added read_bytes() and write_bytes(), to reduce tedious loops.
+ - Added ds2408 example.
+ Delete very old, out-of-date readme file (info is here)
+
+Version 2.0: Modifications by Paul Stoffregen, January 2010:
+http://www.pjrc.com/teensy/td_libs_OneWire.html
+ Search fix from Robin James
+ http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1238032295/27#27
+ Use direct optimized I/O in all cases
+ Disable interrupts during timing critical sections
+ (this solves many random communication errors)
+ Disable interrupts during read-modify-write I/O
+ Reduce RAM consumption by eliminating unnecessary
+ variables and trimming many to 8 bits
+ Optimize both crc8 - table version moved to flash
+
+Modified to work with larger numbers of devices - avoids loop.
+Tested in Arduino 11 alpha with 12 sensors.
+26 Sept 2008 -- Robin James
+http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1238032295/27#27
+
+Updated to work with arduino-0008 and to include skip() as of
+2007/07/06. --RJL20
+
+Modified to calculate the 8-bit CRC directly, avoiding the need for
+the 256-byte lookup table to be loaded in RAM. Tested in arduino-0010
+-- Tom Pollard, Jan 23, 2008
+
+Jim Studt's original library was modified by Josh Larios.
+
+Tom Pollard, pollard@alum.mit.edu, contributed around May 20, 2008
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+Much of the code was inspired by Derek Yerger's code, though I don't
+think much of that remains. In any event that was..
+ (copyleft) 2006 by Derek Yerger - Free to distribute freely.
+
+The CRC code was excerpted and inspired by the Dallas Semiconductor
+sample code bearing this copyright.
+//---------------------------------------------------------------------------
+// Copyright (C) 2000 Dallas Semiconductor Corporation, All Rights Reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+// IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES
+// OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+// OTHER DEALINGS IN THE SOFTWARE.
+//
+// Except as contained in this notice, the name of Dallas Semiconductor
+// shall not be used except as stated in the Dallas Semiconductor
+// Branding Policy.
+//--------------------------------------------------------------------------
+*/
+
+#include "OneWire.h"
+
+
+OneWire::OneWire(uint8_t pin)
+{
+ pinMode(pin, INPUT);
+ bitmask = PIN_TO_BITMASK(pin);
+ baseReg = PIN_TO_BASEREG(pin);
+#if ONEWIRE_SEARCH
+ reset_search();
+#endif
+}
+
+
+// Perform the onewire reset function. We will wait up to 250uS for
+// the bus to come high, if it doesn't then it is broken or shorted
+// and we return a 0;
+//
+// Returns 1 if a device asserted a presence pulse, 0 otherwise.
+//
+uint8_t OneWire::reset(void)
+{
+ IO_REG_TYPE mask = bitmask;
+ volatile IO_REG_TYPE *reg IO_REG_ASM = baseReg;
+ uint8_t r;
+ uint8_t retries = 125;
+
+ noInterrupts();
+ DIRECT_MODE_INPUT(reg, mask);
+ interrupts();
+ // wait until the wire is high... just in case
+ do {
+ if (--retries == 0) return 0;
+ delayMicroseconds(2);
+ } while ( !DIRECT_READ(reg, mask));
+
+ noInterrupts();
+ DIRECT_WRITE_LOW(reg, mask);
+ DIRECT_MODE_OUTPUT(reg, mask); // drive output low
+ interrupts();
+ delayMicroseconds(480);
+ noInterrupts();
+ DIRECT_MODE_INPUT(reg, mask); // allow it to float
+ delayMicroseconds(70);
+ r = !DIRECT_READ(reg, mask);
+ interrupts();
+ delayMicroseconds(410);
+ return r;
+}
+
+//
+// Write a bit. Port and bit is used to cut lookup time and provide
+// more certain timing.
+//
+void OneWire::write_bit(uint8_t v)
+{
+ IO_REG_TYPE mask=bitmask;
+ volatile IO_REG_TYPE *reg IO_REG_ASM = baseReg;
+
+ if (v & 1) {
+ noInterrupts();
+ DIRECT_WRITE_LOW(reg, mask);
+ DIRECT_MODE_OUTPUT(reg, mask); // drive output low
+ delayMicroseconds(10);
+ DIRECT_WRITE_HIGH(reg, mask); // drive output high
+ interrupts();
+ delayMicroseconds(55);
+ } else {
+ noInterrupts();
+ DIRECT_WRITE_LOW(reg, mask);
+ DIRECT_MODE_OUTPUT(reg, mask); // drive output low
+ delayMicroseconds(65);
+ DIRECT_WRITE_HIGH(reg, mask); // drive output high
+ interrupts();
+ delayMicroseconds(5);
+ }
+}
+
+//
+// Read a bit. Port and bit is used to cut lookup time and provide
+// more certain timing.
+//
+uint8_t OneWire::read_bit(void)
+{
+ IO_REG_TYPE mask=bitmask;
+ volatile IO_REG_TYPE *reg IO_REG_ASM = baseReg;
+ uint8_t r;
+
+ noInterrupts();
+ DIRECT_MODE_OUTPUT(reg, mask);
+ DIRECT_WRITE_LOW(reg, mask);
+ delayMicroseconds(3);
+ DIRECT_MODE_INPUT(reg, mask); // let pin float, pull up will raise
+ delayMicroseconds(10);
+ r = DIRECT_READ(reg, mask);
+ interrupts();
+ delayMicroseconds(53);
+ return r;
+}
+
+//
+// Write a byte. The writing code uses the active drivers to raise the
+// pin high, if you need power after the write (e.g. DS18S20 in
+// parasite power mode) then set 'power' to 1, otherwise the pin will
+// go tri-state at the end of the write to avoid heating in a short or
+// other mishap.
+//
+void OneWire::write(uint8_t v, uint8_t power /* = 0 */) {
+ uint8_t bitMask;
+
+ for (bitMask = 0x01; bitMask; bitMask <<= 1) {
+ OneWire::write_bit( (bitMask & v)?1:0);
+ }
+ if ( !power) {
+ noInterrupts();
+ DIRECT_MODE_INPUT(baseReg, bitmask);
+ DIRECT_WRITE_LOW(baseReg, bitmask);
+ interrupts();
+ }
+}
+
+void OneWire::write_bytes(const uint8_t *buf, uint16_t count, bool power /* = 0 */) {
+ for (uint16_t i = 0 ; i < count ; i++)
+ write(buf[i]);
+ if (!power) {
+ noInterrupts();
+ DIRECT_MODE_INPUT(baseReg, bitmask);
+ DIRECT_WRITE_LOW(baseReg, bitmask);
+ interrupts();
+ }
+}
+
+//
+// Read a byte
+//
+uint8_t OneWire::read() {
+ uint8_t bitMask;
+ uint8_t r = 0;
+
+ for (bitMask = 0x01; bitMask; bitMask <<= 1) {
+ if ( OneWire::read_bit()) r |= bitMask;
+ }
+ return r;
+}
+
+void OneWire::read_bytes(uint8_t *buf, uint16_t count) {
+ for (uint16_t i = 0 ; i < count ; i++)
+ buf[i] = read();
+}
+
+//
+// Do a ROM select
+//
+void OneWire::select(const uint8_t rom[8])
+{
+ uint8_t i;
+
+ write(0x55); // Choose ROM
+
+ for (i = 0; i < 8; i++) write(rom[i]);
+}
+
+//
+// Do a ROM skip
+//
+void OneWire::skip()
+{
+ write(0xCC); // Skip ROM
+}
+
+void OneWire::depower()
+{
+ noInterrupts();
+ DIRECT_MODE_INPUT(baseReg, bitmask);
+ interrupts();
+}
+
+#if ONEWIRE_SEARCH
+
+//
+// You need to use this function to start a search again from the beginning.
+// You do not need to do it for the first search, though you could.
+//
+void OneWire::reset_search()
+{
+ // reset the search state
+ LastDiscrepancy = 0;
+ LastDeviceFlag = FALSE;
+ LastFamilyDiscrepancy = 0;
+ for(int i = 7; ; i--) {
+ ROM_NO[i] = 0;
+ if ( i == 0) break;
+ }
+}
+
+// Setup the search to find the device type 'family_code' on the next call
+// to search(*newAddr) if it is present.
+//
+void OneWire::target_search(uint8_t family_code)
+{
+ // set the search state to find SearchFamily type devices
+ ROM_NO[0] = family_code;
+ for (uint8_t i = 1; i < 8; i++)
+ ROM_NO[i] = 0;
+ LastDiscrepancy = 64;
+ LastFamilyDiscrepancy = 0;
+ LastDeviceFlag = FALSE;
+}
+
+//
+// Perform a search. If this function returns a '1' then it has
+// enumerated the next device and you may retrieve the ROM from the
+// OneWire::address variable. If there are no devices, no further
+// devices, or something horrible happens in the middle of the
+// enumeration then a 0 is returned. If a new device is found then
+// its address is copied to newAddr. Use OneWire::reset_search() to
+// start over.
+//
+// --- Replaced by the one from the Dallas Semiconductor web site ---
+//--------------------------------------------------------------------------
+// Perform the 1-Wire Search Algorithm on the 1-Wire bus using the existing
+// search state.
+// Return TRUE : device found, ROM number in ROM_NO buffer
+// FALSE : device not found, end of search
+//
+uint8_t OneWire::search(uint8_t *newAddr)
+{
+ uint8_t id_bit_number;
+ uint8_t last_zero, rom_byte_number, search_result;
+ uint8_t id_bit, cmp_id_bit;
+
+ unsigned char rom_byte_mask, search_direction;
+
+ // initialize for search
+ id_bit_number = 1;
+ last_zero = 0;
+ rom_byte_number = 0;
+ rom_byte_mask = 1;
+ search_result = 0;
+
+ // if the last call was not the last one
+ if (!LastDeviceFlag)
+ {
+ // 1-Wire reset
+ if (!reset())
+ {
+ // reset the search
+ LastDiscrepancy = 0;
+ LastDeviceFlag = FALSE;
+ LastFamilyDiscrepancy = 0;
+ return FALSE;
+ }
+
+ // issue the search command
+ write(0xF0);
+
+ // loop to do the search
+ do
+ {
+ // read a bit and its complement
+ id_bit = read_bit();
+ cmp_id_bit = read_bit();
+
+ // check for no devices on 1-wire
+ if ((id_bit == 1) && (cmp_id_bit == 1))
+ break;
+ else
+ {
+ // all devices coupled have 0 or 1
+ if (id_bit != cmp_id_bit)
+ search_direction = id_bit; // bit write value for search
+ else
+ {
+ // if this discrepancy if before the Last Discrepancy
+ // on a previous next then pick the same as last time
+ if (id_bit_number < LastDiscrepancy)
+ search_direction = ((ROM_NO[rom_byte_number] & rom_byte_mask) > 0);
+ else
+ // if equal to last pick 1, if not then pick 0
+ search_direction = (id_bit_number == LastDiscrepancy);
+
+ // if 0 was picked then record its position in LastZero
+ if (search_direction == 0)
+ {
+ last_zero = id_bit_number;
+
+ // check for Last discrepancy in family
+ if (last_zero < 9)
+ LastFamilyDiscrepancy = last_zero;
+ }
+ }
+
+ // set or clear the bit in the ROM byte rom_byte_number
+ // with mask rom_byte_mask
+ if (search_direction == 1)
+ ROM_NO[rom_byte_number] |= rom_byte_mask;
+ else
+ ROM_NO[rom_byte_number] &= ~rom_byte_mask;
+
+ // serial number search direction write bit
+ write_bit(search_direction);
+
+ // increment the byte counter id_bit_number
+ // and shift the mask rom_byte_mask
+ id_bit_number++;
+ rom_byte_mask <<= 1;
+
+ // if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask
+ if (rom_byte_mask == 0)
+ {
+ rom_byte_number++;
+ rom_byte_mask = 1;
+ }
+ }
+ }
+ while(rom_byte_number < 8); // loop until through all ROM bytes 0-7
+
+ // if the search was successful then
+ if (!(id_bit_number < 65))
+ {
+ // search successful so set LastDiscrepancy,LastDeviceFlag,search_result
+ LastDiscrepancy = last_zero;
+
+ // check for last device
+ if (LastDiscrepancy == 0)
+ LastDeviceFlag = TRUE;
+
+ search_result = TRUE;
+ }
+ }
+
+ // if no device found then reset counters so next 'search' will be like a first
+ if (!search_result || !ROM_NO[0])
+ {
+ LastDiscrepancy = 0;
+ LastDeviceFlag = FALSE;
+ LastFamilyDiscrepancy = 0;
+ search_result = FALSE;
+ }
+ for (int i = 0; i < 8; i++) newAddr[i] = ROM_NO[i];
+ return search_result;
+ }
+
+#endif
+
+#if ONEWIRE_CRC
+// The 1-Wire CRC scheme is described in Maxim Application Note 27:
+// "Understanding and Using Cyclic Redundancy Checks with Maxim iButton Products"
+//
+
+#if ONEWIRE_CRC8_TABLE
+// This table comes from Dallas sample code where it is freely reusable,
+// though Copyright (C) 2000 Dallas Semiconductor Corporation
+static const uint8_t PROGMEM dscrc_table[] = {
+ 0, 94,188,226, 97, 63,221,131,194,156,126, 32,163,253, 31, 65,
+ 157,195, 33,127,252,162, 64, 30, 95, 1,227,189, 62, 96,130,220,
+ 35,125,159,193, 66, 28,254,160,225,191, 93, 3,128,222, 60, 98,
+ 190,224, 2, 92,223,129, 99, 61,124, 34,192,158, 29, 67,161,255,
+ 70, 24,250,164, 39,121,155,197,132,218, 56,102,229,187, 89, 7,
+ 219,133,103, 57,186,228, 6, 88, 25, 71,165,251,120, 38,196,154,
+ 101, 59,217,135, 4, 90,184,230,167,249, 27, 69,198,152,122, 36,
+ 248,166, 68, 26,153,199, 37,123, 58,100,134,216, 91, 5,231,185,
+ 140,210, 48,110,237,179, 81, 15, 78, 16,242,172, 47,113,147,205,
+ 17, 79,173,243,112, 46,204,146,211,141,111, 49,178,236, 14, 80,
+ 175,241, 19, 77,206,144,114, 44,109, 51,209,143, 12, 82,176,238,
+ 50,108,142,208, 83, 13,239,177,240,174, 76, 18,145,207, 45,115,
+ 202,148,118, 40,171,245, 23, 73, 8, 86,180,234,105, 55,213,139,
+ 87, 9,235,181, 54,104,138,212,149,203, 41,119,244,170, 72, 22,
+ 233,183, 85, 11,136,214, 52,106, 43,117,151,201, 74, 20,246,168,
+ 116, 42,200,150, 21, 75,169,247,182,232, 10, 84,215,137,107, 53};
+
+//
+// Compute a Dallas Semiconductor 8 bit CRC. These show up in the ROM
+// and the registers. (note: this might better be done without to
+// table, it would probably be smaller and certainly fast enough
+// compared to all those delayMicrosecond() calls. But I got
+// confused, so I use this table from the examples.)
+//
+uint8_t OneWire::crc8(const uint8_t *addr, uint8_t len)
+{
+ uint8_t crc = 0;
+
+ while (len--) {
+ crc = pgm_read_byte(dscrc_table + (crc ^ *addr++));
+ }
+ return crc;
+}
+#else
+//
+// Compute a Dallas Semiconductor 8 bit CRC directly.
+// this is much slower, but much smaller, than the lookup table.
+//
+uint8_t OneWire::crc8(const uint8_t *addr, uint8_t len)
+{
+ uint8_t crc = 0;
+
+ while (len--) {
+ uint8_t inbyte = *addr++;
+ for (uint8_t i = 8; i; i--) {
+ uint8_t mix = (crc ^ inbyte) & 0x01;
+ crc >>= 1;
+ if (mix) crc ^= 0x8C;
+ inbyte >>= 1;
+ }
+ }
+ return crc;
+}
+#endif
+
+#if ONEWIRE_CRC16
+bool OneWire::check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc)
+{
+ crc = ~crc16(input, len, crc);
+ return (crc & 0xFF) == inverted_crc[0] && (crc >> 8) == inverted_crc[1];
+}
+
+uint16_t OneWire::crc16(const uint8_t* input, uint16_t len, uint16_t crc)
+{
+ static const uint8_t oddparity[16] =
+ { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 };
+
+ for (uint16_t i = 0 ; i < len ; i++) {
+ // Even though we're just copying a byte from the input,
+ // we'll be doing 16-bit computation with it.
+ uint16_t cdata = input[i];
+ cdata = (cdata ^ crc) & 0xff;
+ crc >>= 8;
+
+ if (oddparity[cdata & 0x0F] ^ oddparity[cdata >> 4])
+ crc ^= 0xC001;
+
+ cdata <<= 6;
+ crc ^= cdata;
+ cdata <<= 1;
+ crc ^= cdata;
+ }
+ return crc;
+}
+#endif
+
+#endif
--- /dev/null
+#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
+
+#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);
+
+ // Perform a 1-Wire reset cycle. Returns 1 if a device responds
+ // with a presence pulse. Returns 0 if there is no device or the
+ // bus is shorted or otherwise held low for more than 250uS
+ uint8_t reset(void);
+
+ // Issue a 1-Wire rom select command, you do the reset first.
+ void select(const uint8_t rom[8]);
+
+ // Issue a 1-Wire rom skip command, to address all on bus.
+ void skip(void);
+
+ // Write a byte. If 'power' is one then the wire is held high at
+ // the end for parasitically powered devices. You are responsible
+ // for eventually depowering it by calling depower() or doing
+ // another read or write.
+ void write(uint8_t v, uint8_t power = 0);
+
+ void write_bytes(const uint8_t *buf, uint16_t count, bool power = 0);
+
+ // Read a byte.
+ uint8_t read(void);
+
+ void read_bytes(uint8_t *buf, uint16_t count);
+
+ // Write a bit. The bus is always left powered at the end, see
+ // note in write() about that.
+ void write_bit(uint8_t v);
+
+ // Read a bit.
+ uint8_t read_bit(void);
+
+ // Stop forcing power onto the bus. You only need to do this if
+ // you used the 'power' flag to write() or used a write_bit() call
+ // and aren't about to do another read or write. You would rather
+ // not leave this powered if you don't have to, just in case
+ // someone shorts your bus.
+ void depower(void);
+
+#if ONEWIRE_SEARCH
+ // Clear the search state so that if will start from the beginning again.
+ void reset_search();
+
+ // Setup the search to find the device type 'family_code' on the next call
+ // to search(*newAddr) if it is present.
+ void target_search(uint8_t family_code);
+
+ // Look for the next device. Returns 1 if a new address has been
+ // returned. A zero might mean that the bus is shorted, there are
+ // no devices, or you have already retrieved all of them. It
+ // might be a good idea to check the CRC to make sure you didn't
+ // get garbage. The order is deterministic. You will always get
+ // the same devices in the same order.
+ uint8_t search(uint8_t *newAddr);
+#endif
+
+#if ONEWIRE_CRC
+ // Compute a Dallas Semiconductor 8 bit CRC, these are used in the
+ // ROM and scratchpad registers.
+ static uint8_t crc8(const uint8_t *addr, uint8_t len);
+
+#if ONEWIRE_CRC16
+ // Compute the 1-Wire CRC16 and compare it against the received CRC.
+ // Example usage (reading a DS2408):
+ // // Put everything in a buffer so we can compute the CRC easily.
+ // uint8_t buf[13];
+ // buf[0] = 0xF0; // Read PIO Registers
+ // buf[1] = 0x88; // LSB address
+ // buf[2] = 0x00; // MSB address
+ // WriteBytes(net, buf, 3); // Write 3 cmd bytes
+ // ReadBytes(net, buf+3, 10); // Read 6 data bytes, 2 0xFF, 2 CRC16
+ // if (!CheckCRC16(buf, 11, &buf[11])) {
+ // // Handle error.
+ // }
+ //
+ // @param input - Array of bytes to checksum.
+ // @param len - How many bytes to use.
+ // @param inverted_crc - The two CRC16 bytes in the received data.
+ // This should just point into the received data,
+ // *not* at a 16-bit integer.
+ // @param crc - The crc starting value (optional)
+ // @return True, iff the CRC matches.
+ static bool check_crc16(const uint8_t* input, uint16_t len, const uint8_t* inverted_crc, uint16_t crc = 0);
+
+ // Compute a Dallas Semiconductor 16 bit CRC. This is required to check
+ // the integrity of data received from many 1-Wire devices. Note that the
+ // CRC computed here is *not* what you'll get from the 1-Wire network,
+ // for two reasons:
+ // 1) The CRC is transmitted bitwise inverted.
+ // 2) Depending on the endian-ness of your processor, the binary
+ // representation of the two-byte return value may have a different
+ // byte order than the two bytes you get from 1-Wire.
+ // @param input - Array of bytes to checksum.
+ // @param len - How many bytes to use.
+ // @param crc - The crc starting value (optional)
+ // @return The CRC16, as defined by Dallas Semiconductor.
+ static uint16_t crc16(const uint8_t* input, uint16_t len, uint16_t crc = 0);
+#endif
+#endif
+};
+
+#endif
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