--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/components/esp32-owb/owb.c Tue Oct 08 12:00:31 2019 +0200
@@ -0,0 +1,570 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2017 David Antliff
+ * Copyright (c) 2017 Chris Morgan <chmorgan@gmail.com>
+ *
+ * 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.
+ */
+
+/**
+ * @file
+ */
+
+#include <stddef.h>
+#include <stdbool.h>
+#include <inttypes.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_log.h"
+#include "sdkconfig.h"
+#include "driver/gpio.h"
+
+#include "owb.h"
+#include "owb_gpio.h"
+
+static const char * TAG = "owb";
+
+static bool _is_init(const OneWireBus * bus)
+{
+ bool ok = false;
+ if (bus != NULL)
+ {
+ if (bus->driver)
+ {
+ // OK
+ ok = true;
+ }
+ else
+ {
+ ESP_LOGE(TAG, "bus is not initialised");
+ }
+ }
+ else
+ {
+ ESP_LOGE(TAG, "bus is NULL");
+ }
+ return ok;
+}
+
+/**
+ * @brief 1-Wire 8-bit CRC lookup.
+ * @param[in] crc Starting CRC value. Pass in prior CRC to accumulate.
+ * @param[in] data Byte to feed into CRC.
+ * @return Resultant CRC value.
+ */
+static uint8_t _calc_crc(uint8_t crc, uint8_t data)
+{
+ // https://www.maximintegrated.com/en/app-notes/index.mvp/id/27
+ static const uint8_t table[256] = {
+ 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
+ };
+
+ return table[crc ^ data];
+}
+
+static uint8_t _calc_crc_block(uint8_t crc, const uint8_t * buffer, size_t len)
+{
+ do
+ {
+ crc = _calc_crc(crc, *buffer++);
+ ESP_LOGD(TAG, "crc 0x%02x, len %d", (int)crc, (int)len);
+ }
+ while (--len > 0);
+ return crc;
+}
+
+/**
+ * @param[out] is_found true if a device was found, false if not
+ * @return status
+ */
+static owb_status _search(const OneWireBus * bus, OneWireBus_SearchState * state, bool *is_found)
+{
+ // Based on https://www.maximintegrated.com/en/app-notes/index.mvp/id/187
+
+ // initialize for search
+ int id_bit_number = 1;
+ int last_zero = 0;
+ int rom_byte_number = 0;
+ uint8_t id_bit = 0;
+ uint8_t cmp_id_bit = 0;
+ uint8_t rom_byte_mask = 1;
+ uint8_t search_direction = 0;
+ bool search_result = false;
+ uint8_t crc8 = 0;
+ owb_status status;
+
+ // if the last call was not the last one
+ if (!state->last_device_flag)
+ {
+ // 1-Wire reset
+ bool is_present;
+ bus->driver->reset(bus, &is_present);
+ if (!is_present)
+ {
+ // reset the search
+ state->last_discrepancy = 0;
+ state->last_device_flag = false;
+ state->last_family_discrepancy = 0;
+ *is_found = false;
+ return OWB_STATUS_OK;
+ }
+
+ // issue the search command
+ bus->driver->write_bits(bus, OWB_ROM_SEARCH, 8);
+
+ // loop to do the search
+ do
+ {
+ id_bit = cmp_id_bit = 0;
+
+ // read a bit and its complement
+ bus->driver->read_bits(bus, &id_bit, 1);
+ bus->driver->read_bits(bus, &cmp_id_bit, 1);
+
+ // check for no devices on 1-wire (signal level is high in both bit reads)
+ if (id_bit && cmp_id_bit)
+ {
+ break;
+ } else
+ {
+ // all devices coupled have 0 or 1
+ if (id_bit != cmp_id_bit)
+ {
+ search_direction = (id_bit) ? 1 : 0; // 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 < state->last_discrepancy)
+ search_direction = ((state->rom_code.bytes[rom_byte_number] & rom_byte_mask) > 0);
+ else
+ // if equal to last pick 1, if not then pick 0
+ search_direction = (id_bit_number == state->last_discrepancy);
+
+ // 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)
+ state->last_family_discrepancy = last_zero;
+ }
+ }
+
+ // set or clear the bit in the ROM byte rom_byte_number
+ // with mask rom_byte_mask
+ if (search_direction == 1)
+ state->rom_code.bytes[rom_byte_number] |= rom_byte_mask;
+ else
+ state->rom_code.bytes[rom_byte_number] &= ~rom_byte_mask;
+
+ // serial number search direction write bit
+ bus->driver->write_bits(bus, search_direction, 1);
+
+ // 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)
+ {
+ crc8 = owb_crc8_byte(crc8, state->rom_code.bytes[rom_byte_number]); // accumulate the CRC
+ 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) || (crc8 != 0)))
+ {
+ // search successful so set LastDiscrepancy,LastDeviceFlag,search_result
+ state->last_discrepancy = last_zero;
+
+ // check for last device
+ if (state->last_discrepancy == 0)
+ state->last_device_flag = true;
+
+ search_result = true;
+ }
+ }
+
+ // if no device found then reset counters so next 'search' will be like a first
+ if (!search_result || !state->rom_code.bytes[0])
+ {
+ state->last_discrepancy = 0;
+ state->last_device_flag = false;
+ state->last_family_discrepancy = 0;
+ search_result = false;
+ }
+
+ status = OWB_STATUS_OK;
+
+ *is_found = search_result;
+
+ return status;
+}
+
+// Public API
+
+owb_status owb_uninitialize(OneWireBus * bus)
+{
+ owb_status status;
+
+ if(!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ bus->driver->uninitialize(bus);
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+owb_status owb_use_crc(OneWireBus * bus, bool use_crc)
+{
+ owb_status status;
+
+ if(!bus)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ bus->use_crc = use_crc;
+ ESP_LOGD(TAG, "use_crc %d", bus->use_crc);
+
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+owb_status owb_read_rom(const OneWireBus * bus, OneWireBus_ROMCode *rom_code)
+{
+ owb_status status;
+
+ memset(rom_code, 0, sizeof(OneWireBus_ROMCode));
+
+ if(!bus || !rom_code)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ bool is_present;
+ bus->driver->reset(bus, &is_present);
+ if (is_present)
+ {
+ uint8_t value = OWB_ROM_READ;
+ bus->driver->write_bits(bus, value, 8);
+ owb_read_bytes(bus, rom_code->bytes, sizeof(OneWireBus_ROMCode));
+
+ if (bus->use_crc)
+ {
+ if (owb_crc8_bytes(0, rom_code->bytes, sizeof(OneWireBus_ROMCode)) != 0)
+ {
+ ESP_LOGE(TAG, "CRC failed");
+ memset(rom_code->bytes, 0, sizeof(OneWireBus_ROMCode));
+ status = OWB_STATUS_CRC_FAILED;
+ } else
+ {
+ status = OWB_STATUS_OK;
+ }
+ } else
+ {
+ status = OWB_STATUS_OK;
+ }
+ char rom_code_s[OWB_ROM_CODE_STRING_LENGTH];
+ owb_string_from_rom_code(*rom_code, rom_code_s, sizeof(rom_code_s));
+ ESP_LOGD(TAG, "rom_code %s", rom_code_s);
+ }
+ else
+ {
+ status = OWB_STATUS_DEVICE_NOT_RESPONDING;
+ ESP_LOGE(TAG, "ds18b20 device not responding");
+ }
+ }
+
+ return status;
+}
+
+owb_status owb_verify_rom(const OneWireBus * bus, OneWireBus_ROMCode rom_code, bool* is_present)
+{
+ owb_status status;
+ bool result = false;
+
+ if (!bus || !is_present)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ }
+ else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ }
+ else
+ {
+ OneWireBus_SearchState state = {
+ .last_discrepancy = 64,
+ .last_device_flag = false,
+ };
+
+ bool is_found = false;
+ while (!state.last_device_flag && !is_found)
+ {
+ _search(bus, &state, &is_found);
+ if (is_found)
+ {
+ result = true;
+ for (int i = 0; i < sizeof(state.rom_code.bytes) && result; ++i)
+ {
+ result = rom_code.bytes[i] == state.rom_code.bytes[i];
+ ESP_LOGD(TAG, "%02x %02x", rom_code.bytes[i], state.rom_code.bytes[i]);
+ }
+ is_found = result;
+ }
+ }
+
+ ESP_LOGD(TAG, "rom code %sfound", result ? "" : "not ");
+ *is_present = result;
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+owb_status owb_reset(const OneWireBus * bus, bool* a_device_present)
+{
+ owb_status status;
+
+ if(!bus || !a_device_present)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if(!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ bus->driver->reset(bus, a_device_present);
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+owb_status owb_write_byte(const OneWireBus * bus, uint8_t data)
+{
+ owb_status status;
+
+ if(!bus)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ bus->driver->write_bits(bus, data, 8);
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+owb_status owb_read_byte(const OneWireBus * bus, uint8_t *out)
+{
+ owb_status status;
+
+ if(!bus || !out)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ bus->driver->read_bits(bus, out, 8);
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+owb_status owb_read_bytes(const OneWireBus * bus, uint8_t * buffer, unsigned int len)
+{
+ owb_status status;
+
+ if(!bus || !buffer)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ for (int i = 0; i < len; ++i)
+ {
+ uint8_t out;
+ bus->driver->read_bits(bus, &out, 8);
+ buffer[i] = out;
+ }
+
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+owb_status owb_write_bytes(const OneWireBus * bus, const uint8_t * buffer, unsigned int len)
+{
+ owb_status status;
+
+ if(!bus || !buffer)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ for (int i = 0; i < len; i++)
+ {
+ bus->driver->write_bits(bus, buffer[i], 8);
+ }
+
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+owb_status owb_write_rom_code(const OneWireBus * bus, OneWireBus_ROMCode rom_code)
+{
+ owb_status status;
+
+ if(!bus)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ owb_write_bytes(bus, (uint8_t*)&rom_code, sizeof(rom_code));
+ status = OWB_STATUS_OK;
+ }
+
+ return status;
+}
+
+uint8_t owb_crc8_byte(uint8_t crc, uint8_t data)
+{
+ return _calc_crc(crc, data);
+}
+
+uint8_t owb_crc8_bytes(uint8_t crc, const uint8_t * data, size_t len)
+{
+ return _calc_crc_block(crc, data, len);
+}
+
+owb_status owb_search_first(const OneWireBus * bus, OneWireBus_SearchState * state, bool* found_device)
+{
+ bool result;
+ owb_status status;
+
+ if(!bus || !state || !found_device)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ memset(&state->rom_code, 0, sizeof(state->rom_code));
+ state->last_discrepancy = 0;
+ state->last_family_discrepancy = 0;
+ state->last_device_flag = false;
+ _search(bus, state, &result);
+ status = OWB_STATUS_OK;
+
+ *found_device = result;
+ }
+
+ return status;
+}
+
+owb_status owb_search_next(const OneWireBus * bus, OneWireBus_SearchState * state, bool* found_device)
+{
+ owb_status status;
+ bool result = false;
+
+ if(!bus || !state || !found_device)
+ {
+ status = OWB_STATUS_PARAMETER_NULL;
+ } else if (!_is_init(bus))
+ {
+ status = OWB_STATUS_NOT_INITIALIZED;
+ } else
+ {
+ _search(bus, state, &result);
+ status = OWB_STATUS_OK;
+
+ *found_device = result;
+ }
+
+ return status;
+}
+
+char * owb_string_from_rom_code(OneWireBus_ROMCode rom_code, char * buffer, size_t len)
+{
+ for (int i = sizeof(rom_code.bytes) - 1; i >= 0; i--)
+ {
+ sprintf(buffer, "%02x", rom_code.bytes[i]);
+ buffer += 2;
+ }
+ return buffer;
+}