Руслан Бредун
test
Diff: DS1820/OneWire/OneWire.cpp
- Revision:
- 11:32eeb052cda5
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/DS1820/OneWire/OneWire.cpp Wed Aug 26 14:26:27 2020 +0530
@@ -0,0 +1,513 @@
+/*
+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+ Delete very old, out-of-date readme file (info is here)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.
+ * But because for STM chips it takes very long time to change from output
+ * to input an open drain mode is used rather and the GPIO remains output forever.
+ * @param
+ * @retval
+ */
+OneWire::OneWire(PinName pin, int sample_point_us /* = 13 */) :
+ DigitalInOut(pin),
+ _sample_point_us(sample_point_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();
+ _out_to_in_transition_us = timer.read_us();
+
+ MBED_ASSERT(_out_to_in_transition_us < _sample_point_us);
+
+ INIT_WAIT;
+#if ONEWIRE_SEARCH
+ reset_search();
+#endif
+}
+
+/**
+ * @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;
+
+ 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);
+
+ 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)
+{
+ OUTPUT();
+ if (v & 1) {
+ WRITE(0); // drive output low
+ WAIT_US(1);
+ WRITE(1); // drive output high
+ WAIT_US(60);
+ }
+ else {
+ WRITE(0); // drive output low
+ WAIT_US(60);
+ WRITE(1); // drive output high
+ WAIT_US(1);
+ }
+}
+
+/**
+ * @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;
+
+ OUTPUT();
+ WRITE(0);
+ INPUT();
+ wait_us(_sample_point_us - _out_to_in_transition_us); // wait till sample point
+ r = READ();
+ WAIT_US(55);
+ 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)
+ 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)
+ 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()
+{
+ 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