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FilamentBox/lib/DS1820/OneWire.cpp
Emanuele Trabattoni 392872d95e Added all useful libraires
2024-06-25 13:19:26 +02:00

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/*
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_Onehtml
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 One 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Delete very old, out-of-date readme file (info is here)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_Onehtml
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"
/**
* @brief Constructs a OneWire object.
* @note GPIO is configured as output and an internal pull up resistor is connected.
* An addition 4.7k Ohm resistor can connected between the 1-wire data bus/line
* and the +3.3V pin,
*
* ----------------
* | | -----------------------> +3.3V
* | MBED BOARD | |
* | | | ------
* | +3.3V |--o--| 4.7k |-------
* | | ------ |
* | | |
* | | |
* | | |
* | | |
* | GPIO |--------------------o-----> 1-wire bus/line
* | |
* | |
* | GND |--------------------------> GND
* | |
* ----------------
*
* @param gpioPin GPIO pin to be used as 1-wire bus/line
* @retval
*/
OneWire::OneWire(PinName gpioPin, int samplePoint_us /*= 13*/) :
_gpio(new DigitalInOut(gpioPin)),
_uart(NULL),
_samplePoint_us(samplePoint_us)
{
Timer timer;
MODE(); // set mode to either OpenDrain for STM or PullUp for others
// Measure bus transition time from ouput to input
timer.reset();
OUTPUT(); // set as output
WRITE(0); // pull the line down
timer.start();
INPUT(); // set as input (and release the bus)
timer.stop();
#if (MBED_MAJOR_VERSION > 5)
_outToInTransition_us = timer.elapsed_time().count();
#else
_outToInTransition_us = timer.read_us();
#endif
MBED_ASSERT(_outToInTransition_us < _samplePoint_us);
INIT_WAIT;
#if ONEWIRE_SEARCH
reset_search();
#endif
}
/**
* @brief Constructs a OneWire object.
* @note UART is used to implement a 1-Wire Bus Master according to Maxim Integrated application note
*
* https://www.maximintegrated.com/en/design/technical-documents/tutorials/2/214.html
*
* In addition to the 4.7k Ohm resistor between the 1-wire data bus/line and the +3.3V pin,
* a 470 Ohm resistor shall be tied to the UART's tx and rx pin. UART's rx pin is then used
* as 1-wire data bus/line.
*
* ----------------
* | | -----------------------> +3.3V
* | MBED BOARD | |
* | | | ------
* | +3.3V |--o--| 4.7k |-------
* | | ------ |
* | | ------ |
* | UART TX |-----| 470 |--- |
* | | ------ | |
* | | | |
* | UART RX |----------------o---o-----> 1-wire bus/line
* | |
* | |
* | GND |--------------------------> GND
* | |
* ----------------
*
* @param txPin UART's Tx pin name
* @param rxPin UART's Rx pin name
* @retval
*/
OneWire::OneWire(PinName txPin, PinName rxPin, int baud /*=115200*/) :
_gpio(NULL),
_uart(new UART(txPin, rxPin, baud))
{
#if ONEWIRE_SEARCH
reset_search();
#endif
}
OneWire::~OneWire()
{
if (_gpio != NULL)
delete _gpio;
if (_uart != NULL)
delete _uart;
}
/**
* @brief Performs the onewire reset function.
* @note 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;
* @param
* @retval 1 if a device asserted a presence pulse, 0 otherwise.
*/
uint8_t OneWire::reset(void)
{
uint8_t present;
if (_gpio != NULL) {
OUTPUT();
WRITE(0); // pull down the 1-wire bus do create reset pulse
WAIT_US(500); // wait at least 480 us
INPUT(); // release the 1-wire bus and go into receive mode
WAIT_US(90); // DS1820 waits about 15 to 60 us and generates a 60 to 240 us presence pulse
present = !READ(); // read the presence pulse
WAIT_US(420);
}
else {
_uart->baud(9600);
#if (MBED_MAJOR_VERSION > 5)
ThisThread::sleep_for(10ms);
#else
wait_ms(10);
#endif
_uart->_base_putc(0xF0);
present = _uart->_base_getc();
wait_us(420);
_uart->baud(115200);
#if (MBED_MAJOR_VERSION > 5)
ThisThread::sleep_for(10ms);
#else
wait_ms(10);
#endif
present = (present >= 0x10);
}
return present;
}
/**
* @brief Writes a bit.
* @note GPIO registers are used for STM chips to cut time.
* @param
* @retval
*/
void OneWire::write_bit(uint8_t v)
{
if (v & 1) {
if (_gpio != NULL) {
OUTPUT();
WRITE(0); // drive output low
WAIT_US(1);
WRITE(1); // drive output high
WAIT_US(60);
}
else {
_uart->_base_putc(0xFF);
}
}
else {
if (_gpio != NULL) {
OUTPUT();
WRITE(0); // drive output low
WAIT_US(60);
WRITE(1); // drive output high
WAIT_US(1);
}
else {
_uart->_base_putc(0x00);
}
}
}
/**
* @brief Reads a bit.
* @note GPIO registers are used for STM chips to cut time.
* @param
* @retval
*/
uint8_t OneWire::read_bit(void)
{
uint8_t r;
if (_gpio != NULL) {
OUTPUT();
WRITE(0);
INPUT();
wait_us(_samplePoint_us - _outToInTransition_us); // wait till sample point
r = READ();
WAIT_US(55);
}
else {
_uart->_base_putc(0xFF);
do {
r = _uart->_base_getc();
wait_us(100);
} while(_uart->readable());
r = r & 0x01;
}
return r;
}
/**
* @brief Writes a byte.
* @note 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.
* @param
* @retval
*/
void OneWire::write_byte(uint8_t v, uint8_t power /* = 0 */ )
{
uint8_t bitMask;
for (bitMask = 0x01; bitMask; bitMask <<= 1)
write_bit((bitMask & v) ? 1 : 0);
if ((!power) && (_gpio != NULL))
INPUT();
}
/**
* @brief Writes bytes.
* @note
* @param
* @retval
*/
void OneWire::write_bytes(const uint8_t* buf, uint16_t count, bool power /* = 0 */ )
{
for (uint16_t i = 0; i < count; i++)
write_byte(buf[i]);
if ((!power) && (_gpio != NULL))
INPUT();
}
/**
* @brief Reads a byte.
* @note
* @param
* @retval
*/
uint8_t OneWire::read_byte()
{
uint8_t bitMask;
uint8_t r = 0;
for (bitMask = 0x01; bitMask; bitMask <<= 1) {
if (read_bit())
r |= bitMask;
}
return r;
}
/**
* @brief Reads bytes.
* @note
* @param
* @retval
*/
void OneWire::read_bytes(uint8_t* buf, uint16_t count)
{
for (uint16_t i = 0; i < count; i++)
buf[i] = read_byte();
}
/**
* @brief Selects ROM.
* @note
* @param
* @retval
*/
void OneWire::select(const uint8_t rom[8])
{
uint8_t i;
write_byte(0x55); // Choose ROM
for (i = 0; i < 8; i++)
write_byte(rom[i]);
}
/**
* @brief Skips ROM select.
* @note
* @param
* @retval
*/
void OneWire::skip()
{
write_byte(0xCC); // Skip ROM
}
/**
* @brief Unpowers the chip.
* @note
* @param
* @retval
*/
void OneWire::depower()
{
if (_gpio != NULL)
INPUT();
}
#if ONEWIRE_SEARCH
//
/**
* @brief Resets the search state.
* @note We need to use this function to start a search again from the beginning.
* We do not need to do it for the first search, though we could.
* @param
* @retval
*/
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;
}
}
/**
* @brief Sets the search state to find SearchFamily type devices.
* @note
* @param
* @retval
*/
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;
}
/**
* @brief Performs a search.
* @note 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.
* @param
* @retval 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_byte(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
//
/**
* @brief Computes a Dallas Semiconductor 8 bit CRC directly.
* @note The 1-Wire CRC scheme is described in Maxim Application Note 27:
"Understanding and Using Cyclic Redundancy Checks with Maxim iButton Products"
* @param
* @retval
*/
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
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