commit 47b062c08af1e4c1f0d3c24e2840fdbf9045c9bf Author: Alexey Zholtikov Date: Fri May 31 10:37:32 2024 +0300 Version 1.0.0 Initial version. diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..496ee2c --- /dev/null +++ b/.gitignore @@ -0,0 +1 @@ +.DS_Store \ No newline at end of file diff --git a/CMakeLists.txt b/CMakeLists.txt new file mode 100644 index 0000000..5ffcfe1 --- /dev/null +++ b/CMakeLists.txt @@ -0,0 +1 @@ +idf_component_register(SRCS "zh_onewire.c" INCLUDE_DIRS "include" REQUIRES driver) \ No newline at end of file diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..137069b --- /dev/null +++ b/LICENSE @@ -0,0 +1,73 @@ +Apache License +Version 2.0, January 2004 +http://www.apache.org/licenses/ + +TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + +1. Definitions. + +"License" shall mean the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document. + +"Licensor" shall mean the copyright owner or entity authorized by the copyright owner that is granting the License. + +"Legal Entity" shall mean the union of the acting entity and all other entities that control, are controlled by, or are under common control with that entity. For the purposes of this definition, "control" means (i) the power, direct or indirect, to cause the direction or management of such entity, whether by contract or otherwise, or (ii) ownership of fifty percent (50%) or more of the outstanding shares, or (iii) beneficial ownership of such entity. + +"You" (or "Your") shall mean an individual or Legal Entity exercising permissions granted by this License. + +"Source" form shall mean the preferred form for making modifications, including but not limited to software source code, documentation source, and configuration files. + +"Object" form shall mean any form resulting from mechanical transformation or translation of a Source form, including but not limited to compiled object code, generated documentation, and conversions to other media types. + +"Work" shall mean the work of authorship, whether in Source or Object form, made available under the License, as indicated by a copyright notice that is included in or attached to the work (an example is provided in the Appendix below). + +"Derivative Works" shall mean any work, whether in Source or Object form, that is based on (or derived from) the Work and for which the editorial revisions, annotations, elaborations, or other modifications represent, as a whole, an original work of authorship. For the purposes of this License, Derivative Works shall not include works that remain separable from, or merely link (or bind by name) to the interfaces of, the Work and Derivative Works thereof. + +"Contribution" shall mean any work of authorship, including the original version of the Work and any modifications or additions to that Work or Derivative Works thereof, that is intentionally submitted to Licensor for inclusion in the Work by the copyright owner or by an individual or Legal Entity authorized to submit on behalf of the copyright owner. For the purposes of this definition, "submitted" means any form of electronic, verbal, or written communication sent to the Licensor or its representatives, including but not limited to communication on electronic mailing lists, source code control systems, and issue tracking systems that are managed by, or on behalf of, the Licensor for the purpose of discussing and improving the Work, but excluding communication that is conspicuously marked or otherwise designated in writing by the copyright owner as "Not a Contribution." + +"Contributor" shall mean Licensor and any individual or Legal Entity on behalf of whom a Contribution has been received by Licensor and subsequently incorporated within the Work. + +2. Grant of Copyright License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare Derivative Works of, publicly display, publicly perform, sublicense, and distribute the Work and such Derivative Works in Source or Object form. + +3. Grant of Patent License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work, where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted. If You institute patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that the Work or a Contribution incorporated within the Work constitutes direct or contributory patent infringement, then any patent licenses granted to You under this License for that Work shall terminate as of the date such litigation is filed. + +4. Redistribution. You may reproduce and distribute copies of the Work or Derivative Works thereof in any medium, with or without modifications, and in Source or Object form, provided that You meet the following conditions: + + (a) You must give any other recipients of the Work or Derivative Works a copy of this License; and + + (b) You must cause any modified files to carry prominent notices stating that You changed the files; and + + (c) You must retain, in the Source form of any Derivative Works that You distribute, all copyright, patent, trademark, and attribution notices from the Source form of the Work, excluding those notices that do not pertain to any part of the Derivative Works; and + + (d) If the Work includes a "NOTICE" text file as part of its distribution, then any Derivative Works that You distribute must include a readable copy of the attribution notices contained within such NOTICE file, excluding those notices that do not pertain to any part of the Derivative Works, in at least one of the following places: within a NOTICE text file distributed as part of the Derivative Works; within the Source form or documentation, if provided along with the Derivative Works; or, within a display generated by the Derivative Works, if and wherever such third-party notices normally appear. The contents of the NOTICE file are for informational purposes only and do not modify the License. You may add Your own attribution notices within Derivative Works that You distribute, alongside or as an addendum to the NOTICE text from the Work, provided that such additional attribution notices cannot be construed as modifying the License. + + You may add Your own copyright statement to Your modifications and may provide additional or different license terms and conditions for use, reproduction, or distribution of Your modifications, or for any such Derivative Works as a whole, provided Your use, reproduction, and distribution of the Work otherwise complies with the conditions stated in this License. + +5. Submission of Contributions. Unless You explicitly state otherwise, any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of this License, without any additional terms or conditions. Notwithstanding the above, nothing herein shall supersede or modify the terms of any separate license agreement you may have executed with Licensor regarding such Contributions. + +6. Trademarks. This License does not grant permission to use the trade names, trademarks, service marks, or product names of the Licensor, except as required for reasonable and customary use in describing the origin of the Work and reproducing the content of the NOTICE file. + +7. Disclaimer of Warranty. Unless required by applicable law or agreed to in writing, Licensor provides the Work (and each Contributor provides its Contributions) on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You are solely responsible for determining the appropriateness of using or redistributing the Work and assume any risks associated with Your exercise of permissions under this License. + +8. Limitation of Liability. In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall any Contributor be liable to You for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising as a result of this License or out of the use or inability to use the Work (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if such Contributor has been advised of the possibility of such damages. + +9. Accepting Warranty or Additional Liability. While redistributing the Work or Derivative Works thereof, You may choose to offer, and charge a fee for, acceptance of support, warranty, indemnity, or other liability obligations and/or rights consistent with this License. However, in accepting such obligations, You may act only on Your own behalf and on Your sole responsibility, not on behalf of any other Contributor, and only if You agree to indemnify, defend, and hold each Contributor harmless for any liability incurred by, or claims asserted against, such Contributor by reason of your accepting any such warranty or additional liability. + +END OF TERMS AND CONDITIONS + +APPENDIX: How to apply the Apache License to your work. + +To apply the Apache License to your work, attach the following boilerplate notice, with the fields enclosed by brackets "[]" replaced with your own identifying information. (Don't include the brackets!) The text should be enclosed in the appropriate comment syntax for the file format. We also recommend that a file or class name and description of purpose be included on the same "printed page" as the copyright notice for easier identification within third-party archives. + +Copyright [yyyy] [name of copyright owner] + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + +http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. diff --git a/README.md b/README.md new file mode 100644 index 0000000..2db1c4a --- /dev/null +++ b/README.md @@ -0,0 +1,62 @@ +# ESP32 ESP-IDF and ESP8266 RTOS SDK component for 1-Wire interface + +## Tested on + +1. ESP8266 RTOS_SDK v3.4 +2. ESP32 ESP-IDF v5.2 + +## [Function description](http://zh-onewire.zh.com.ru) + +## Using + +In an existing project, run the following command to install the component: + +```text +cd ../your_project/components +git clone https://github.com/aZholtikov/zh_onewire.git +``` + +In the application, add the component: + +```c +#include "zh_onewire.h" +``` + +## Example + +Search 1-Wire devices on bus: + +```c +#include "zh_onewire.h" + +void app_main(void) +{ + uint8_t *rom = NULL; + zh_onewire_init(GPIO_NUM_5); + if (zh_onewire_reset() != ESP_OK) + { + printf("There are no 1-Wire devices available on the bus.\n"); + } + else + { + zh_onewire_search_rom_init(); + for (;;) + { + rom = zh_onewire_search_rom_next(); + if (rom == NULL) + { + break; + } + printf("Found device ROM: "); + for (uint8_t i = 0; i < 8; ++i) + { + printf("%X ", *(rom++)); + } + rom -= 8; + printf("\n"); + } + } +} +``` + +Any [feedback](mailto:github@azholtikov.ru) will be gladly accepted. diff --git a/component.mk b/component.mk new file mode 100644 index 0000000..e69de29 diff --git a/include/zh_onewire.h b/include/zh_onewire.h new file mode 100644 index 0000000..6e007f1 --- /dev/null +++ b/include/zh_onewire.h @@ -0,0 +1,115 @@ +/** + * @file + * Header file for the zh_onewire component. + * + */ + +#pragma once + +#include "stdio.h" +#include "freertos/FreeRTOS.h" +#include "freertos/task.h" +#include "driver/gpio.h" +#include "rom/ets_sys.h" +#include "esp_err.h" +#include "esp_log.h" + +#ifdef __cplusplus +extern "C" +{ +#endif + + /** + * @brief Initialize 1-Wire interface. + * + * @param[in] pin 1-Wire bus gpio connection. + * + * @return + * - ESP_OK if initialization was successful + * - ESP_ERR_INVALID_ARG if select incorrect gpio number + */ + esp_err_t zh_onewire_init(const uint8_t pin); + + /** + * @brief Reset command for all 1-Wire devices on bus. + * + * @return + * - ESP_OK if reset was successful + * - ESP_ERR_INVALID_STATE if 1-Wire bus not initialized + * - ESP_ERR_INVALID_RESPONSE if the bus is busy + * - ESP_ERR_TIMEOUT if there are no 1-Wire devices available on the bus or the devices are not responding + */ + esp_err_t zh_onewire_reset(void); + + /** + * @brief Send one byte to 1-Wire device. + * + * @param[in] byte Byte value. + */ + void zh_onewire_send_byte(uint8_t byte); + + /** + * @brief Read one byte from 1-Wire device. + * + * @return Byte value + */ + uint8_t zh_onewire_read_byte(void); + + /** + * @brief Initialize the bus master to address all 1-Wire devices on the bus. + * + * @return + * - ESP_OK if initialization was successful + * - ESP_ERR_INVALID_STATE if 1-Wire bus not initialized + * - ESP_FAIL if there are no 1-Wire devices available on the bus or the devices are not responding + */ + esp_err_t zh_onewire_skip_rom(void); + + /** + * @brief Read rom value if only one 1-Wire device is present on the bus. + * + * @param[out] buf Pointer to a buffer containing an eight-byte rom value. + * + * @return + * - ESP_OK if read was successful + * - ESP_ERR_INVALID_STATE if 1-Wire bus not initialized + * - ESP_FAIL if there are no 1-Wire devices available on the bus or the devices are not responding + * - ESP_ERR_INVALID_CRC if more than one 1-Wire device is present on the bus + */ + esp_err_t zh_onewire_read_rom(uint8_t *buf); + + /** + * @brief Initialize the bus master to address a specific 1-Wire device on bus. + * + * @param[in] data Pointer to a buffer containing an eight-byte rom value. + * + * @return + * - ESP_OK if initialization was successful + * - ESP_ERR_INVALID_STATE if 1-Wire bus not initialized + * - ESP_FAIL if there are no 1-Wire devices available on the bus or the devices are not responding + */ + esp_err_t zh_onewire_match_rom(const uint8_t *data); + + /** + * @brief Initialize search 1-Wire devices on bus. + * + * @return + * - ESP_OK if initialization was successful + * - ESP_ERR_INVALID_STATE if 1-Wire bus not initialized + */ + esp_err_t zh_onewire_search_rom_init(void); + + /** + * @brief Search next 1-Wire device on bus. + * + * @attention Initialize search 1-Wire devices on bus must be initialized first. @code zh_onewire_search_rom_init() @endcode + * + * @return + * - Pointer to a buffer containing an eight-byte rom value + * - NULL if the search is terminated or if there are no 1-Wire devices available on the bus or the devices are not responding or if 1-Wire bus not initialized + */ + uint8_t *zh_onewire_search_rom_next(void); + +#ifdef __cplusplus +} +#endif diff --git a/version.txt b/version.txt new file mode 100644 index 0000000..afaf360 --- /dev/null +++ b/version.txt @@ -0,0 +1 @@ +1.0.0 \ No newline at end of file diff --git a/zh_onewire.c b/zh_onewire.c new file mode 100644 index 0000000..38c182f --- /dev/null +++ b/zh_onewire.c @@ -0,0 +1,367 @@ +/** + * @file + * The main code of the zh_onewire component. + * + */ + +#include "zh_onewire.h" + +/// \cond +#define MASTER_RESET_PULSE_DURATION 480 // Reset time high. Reset time low. +#define RESPONSE_MAX_DURATION 60 // Presence detect high. +#define PRESENCE_PULSE_MAX_DURATION 240 // Presence detect low. +#define RECOVERY_DURATION 1 // Bus recovery time. +#define TIME_SLOT_START_DURATION 1 // Time slot start. +#define TIME_SLOT_DURATION 120 // Time slot. +#define VALID_DATA_DURATION 15 // Valid data duration. + +#define SKIP_ROM 0xCC +#define MATCH_ROM 0x55 +#define READ_ROM 0x33 +#define SEARCH_ROM 0xF0 + +#define pgm_read_byte(addr) (*(const uint8_t *)(addr)) +/// \endcond + +static uint8_t _read_bit(void); +static void _send_bit(const uint8_t bit); + +/// \cond +#ifdef CONFIG_IDF_TARGET_ESP8266 +#define esp_delay_us(x) os_delay_us(x) +#else +#define esp_delay_us(x) esp_rom_delay_us(x) +#endif +/// \endcond + +static const char *TAG = "zh_onewire"; + +static uint8_t _pin; +static uint8_t _rom[8]; +static uint8_t _rom_fork_bit = 0xFF; +static bool _is_initialized = false; + +static const uint8_t _rom_crc_table[] = { + 0x00, 0x5e, 0xbc, 0xe2, 0x61, 0x3f, 0xdd, 0x83, 0xc2, 0x9c, 0x7e, 0x20, 0xa3, 0xfd, 0x1f, 0x41, + 0x9d, 0xc3, 0x21, 0x7f, 0xfc, 0xa2, 0x40, 0x1e, 0x5f, 0x01, 0xe3, 0xbd, 0x3e, 0x60, 0x82, 0xdc, + 0x23, 0x7d, 0x9f, 0xc1, 0x42, 0x1c, 0xfe, 0xa0, 0xe1, 0xbf, 0x5d, 0x03, 0x80, 0xde, 0x3c, 0x62, + 0xbe, 0xe0, 0x02, 0x5c, 0xdf, 0x81, 0x63, 0x3d, 0x7c, 0x22, 0xc0, 0x9e, 0x1d, 0x43, 0xa1, 0xff, + 0x46, 0x18, 0xfa, 0xa4, 0x27, 0x79, 0x9b, 0xc5, 0x84, 0xda, 0x38, 0x66, 0xe5, 0xbb, 0x59, 0x07, + 0xdb, 0x85, 0x67, 0x39, 0xba, 0xe4, 0x06, 0x58, 0x19, 0x47, 0xa5, 0xfb, 0x78, 0x26, 0xc4, 0x9a, + 0x65, 0x3b, 0xd9, 0x87, 0x04, 0x5a, 0xb8, 0xe6, 0xa7, 0xf9, 0x1b, 0x45, 0xc6, 0x98, 0x7a, 0x24, + 0xf8, 0xa6, 0x44, 0x1a, 0x99, 0xc7, 0x25, 0x7b, 0x3a, 0x64, 0x86, 0xd8, 0x5b, 0x05, 0xe7, 0xb9, + 0x8c, 0xd2, 0x30, 0x6e, 0xed, 0xb3, 0x51, 0x0f, 0x4e, 0x10, 0xf2, 0xac, 0x2f, 0x71, 0x93, 0xcd, + 0x11, 0x4f, 0xad, 0xf3, 0x70, 0x2e, 0xcc, 0x92, 0xd3, 0x8d, 0x6f, 0x31, 0xb2, 0xec, 0x0e, 0x50, + 0xaf, 0xf1, 0x13, 0x4d, 0xce, 0x90, 0x72, 0x2c, 0x6d, 0x33, 0xd1, 0x8f, 0x0c, 0x52, 0xb0, 0xee, + 0x32, 0x6c, 0x8e, 0xd0, 0x53, 0x0d, 0xef, 0xb1, 0xf0, 0xae, 0x4c, 0x12, 0x91, 0xcf, 0x2d, 0x73, + 0xca, 0x94, 0x76, 0x28, 0xab, 0xf5, 0x17, 0x49, 0x08, 0x56, 0xb4, 0xea, 0x69, 0x37, 0xd5, 0x8b, + 0x57, 0x09, 0xeb, 0xb5, 0x36, 0x68, 0x8a, 0xd4, 0x95, 0xcb, 0x29, 0x77, 0xf4, 0xaa, 0x48, 0x16, + 0xe9, 0xb7, 0x55, 0x0b, 0x88, 0xd6, 0x34, 0x6a, 0x2b, 0x75, 0x97, 0xc9, 0x4a, 0x14, 0xf6, 0xa8, + 0x74, 0x2a, 0xc8, 0x96, 0x15, 0x4b, 0xa9, 0xf7, 0xb6, 0xe8, 0x0a, 0x54, 0xd7, 0x89, 0x6b, 0x35}; + +esp_err_t zh_onewire_init(const uint8_t pin) +{ + ESP_LOGI(TAG, "Onewire initialization begin."); + _pin = pin; + gpio_config_t config; + config.intr_type = GPIO_INTR_DISABLE; + config.mode = GPIO_MODE_INPUT; + config.pin_bit_mask = (1ULL << _pin); + config.pull_down_en = GPIO_PULLDOWN_DISABLE; + config.pull_up_en = GPIO_PULLUP_ENABLE; + if (gpio_config(&config) != ESP_OK) + { + ESP_LOGE(TAG, "Onewire initialization fail. Incorrect GPIO number."); + return ESP_ERR_INVALID_ARG; + } + _is_initialized = true; + ESP_LOGI(TAG, "Onewire initialization success."); + return ESP_OK; +} + +esp_err_t zh_onewire_reset(void) +{ + ESP_LOGI(TAG, "Onewire reset begin."); + if (_is_initialized == false) + { + ESP_LOGE(TAG, "Onewire reset fail. Onewire not initialized."); + return ESP_ERR_INVALID_STATE; + } + if (gpio_get_level(_pin) != 1) + { + ESP_LOGE(TAG, "Onewire reset fail. Bus is busy."); + return ESP_ERR_INVALID_RESPONSE; + } + gpio_set_direction(_pin, GPIO_MODE_OUTPUT); + gpio_set_level(_pin, 0); + esp_delay_us(MASTER_RESET_PULSE_DURATION); + gpio_set_level(_pin, 1); + gpio_set_direction(_pin, GPIO_MODE_INPUT); + esp_delay_us(RECOVERY_DURATION); + uint8_t response_time = 0; + while (gpio_get_level(_pin) == 1) + { + if (response_time > RESPONSE_MAX_DURATION) + { + ESP_LOGE(TAG, "Onewire reset fail. Timeout exceeded."); + return ESP_ERR_TIMEOUT; + } + ++response_time; + esp_delay_us(1); + } + uint8_t presence_time = 0; + while (gpio_get_level(_pin) == 0) + { + if (presence_time > PRESENCE_PULSE_MAX_DURATION) + { + ESP_LOGE(TAG, "Onewire reset fail. Timeout exceeded."); + return ESP_ERR_TIMEOUT; + } + ++presence_time; + esp_delay_us(1); + } + esp_delay_us(MASTER_RESET_PULSE_DURATION - response_time - presence_time); + ESP_LOGI(TAG, "Onewire reset success."); + return ESP_OK; +} + +void zh_onewire_send_byte(uint8_t byte) +{ + for (uint8_t i = 0; i < 8; ++i) + { + _send_bit(byte & 1); + byte >>= 1; + } +} + +esp_err_t zh_onewire_skip_rom(void) +{ + ESP_LOGI(TAG, "Onewire skip ROM begin."); + if (_is_initialized == false) + { + ESP_LOGE(TAG, "Onewire skip ROM fail. Onewire not initialized."); + return ESP_ERR_INVALID_STATE; + } + if (zh_onewire_reset() != ESP_OK) + { + ESP_LOGE(TAG, "Onewire skip ROM fail."); + return ESP_FAIL; + } + zh_onewire_send_byte(SKIP_ROM); + ESP_LOGI(TAG, "Onewire skip ROM success."); + return ESP_OK; +} + +esp_err_t zh_onewire_read_rom(uint8_t *buf) +{ + ESP_LOGI(TAG, "Onewire read ROM begin."); + if (_is_initialized == false) + { + ESP_LOGE(TAG, "Onewire read ROM fail. Onewire not initialized."); + return ESP_ERR_INVALID_STATE; + } + if (zh_onewire_reset() != ESP_OK) + { + ESP_LOGE(TAG, "Onewire read ROM fail."); + return ESP_FAIL; + } + zh_onewire_send_byte(READ_ROM); + uint8_t crc = 0; + for (uint8_t i = 0; i < 8; ++i) + { + *buf = zh_onewire_read_byte(); + crc = pgm_read_byte(&_rom_crc_table[crc ^ *buf]); + ++buf; + } + if (crc != 0) + { + ESP_LOGE(TAG, "Onewire read ROM fail. Invalid CRC."); + return ESP_ERR_INVALID_CRC; + } + ESP_LOGI(TAG, "Onewire read ROM success."); + return ESP_OK; +} + +esp_err_t zh_onewire_match_rom(const uint8_t *data) +{ + ESP_LOGI(TAG, "Onewire match ROM begin."); + if (_is_initialized == false) + { + ESP_LOGE(TAG, "Onewire match ROM fail. Onewire not initialized."); + return ESP_ERR_INVALID_STATE; + } + if (zh_onewire_reset() != ESP_OK) + { + ESP_LOGE(TAG, "Onewire match ROM fail."); + return ESP_FAIL; + } + zh_onewire_send_byte(MATCH_ROM); + for (uint8_t i = 0; i < 8; ++i) + { + zh_onewire_send_byte(*(data++)); + } + ESP_LOGI(TAG, "Onewire match ROM success."); + return ESP_OK; +} + +esp_err_t zh_onewire_search_rom_init(void) +{ + if (_is_initialized == false) + { + return ESP_ERR_INVALID_STATE; + } + for (uint8_t i = 0; i < 8; ++i) + { + _rom[i] = 0; + } + _rom_fork_bit = 65; + return ESP_OK; +} + +uint8_t *zh_onewire_search_rom_next(void) +{ + ESP_LOGI(TAG, "Onewire search ROM begin."); + if (_is_initialized == false) + { + ESP_LOGE(TAG, "Onewire search ROM fail. Onewire not initialized."); + return NULL; + } + if (_rom_fork_bit == 0xFF) + { + ESP_LOGE(TAG, "Onewire search ROM not initialized."); + return NULL; + } + if (_rom_fork_bit == 0) + { + ESP_LOGI(TAG, "Onewire search ROM terminated."); + return NULL; + } + if (zh_onewire_reset() != ESP_OK) + { + ESP_LOGE(TAG, "Onewire search ROM fail."); + return NULL; + } + uint8_t bit_position = 8; + uint8_t *p_prev_bit = &_rom[0]; + uint8_t prev_bit = *p_prev_bit; + uint8_t next_bit = 0; + uint8_t counter = 1; + zh_onewire_send_byte(SEARCH_ROM); + uint8_t new_fork = 0; + for (;;) + { + uint8_t bit_not_0 = _read_bit(); + uint8_t bit_not_1 = _read_bit(); + if (bit_not_0 == 0) + { + if (bit_not_1 == 0) + { + if (counter < _rom_fork_bit) + { + if (prev_bit == 1) + { + next_bit |= 0x80; + } + else + { + new_fork = counter; + } + } + else if (counter == _rom_fork_bit) + { + next_bit |= 0x80; + } + else + { + new_fork = counter; + } + } + } + else + { + if (bit_not_1 == 0) + { + next_bit |= 0x80; + } + else + { + ESP_LOGI(TAG, "Onewire search ROM terminated."); + return NULL; + } + } + _send_bit(next_bit & 0x80); + --bit_position; + if (bit_position == 0) + { + *p_prev_bit = next_bit; + if (counter >= 64) + { + break; + } + next_bit = 0; + ++p_prev_bit; + prev_bit = *p_prev_bit; + bit_position = 8; + } + else + { + if (counter >= 64) + { + break; + } + prev_bit >>= 1; + next_bit >>= 1; + } + ++counter; + } + _rom_fork_bit = new_fork; + ESP_LOGI(TAG, "Onewire search ROM success."); + return &_rom[0]; +} + +uint8_t zh_onewire_read_byte(void) +{ + uint8_t byte = 0; + for (uint8_t i = 0; i < 8; ++i) + { + byte >>= 1; + if (_read_bit() != 0) + { + byte |= 0x80; + } + } + return byte; +} + +static uint8_t _read_bit(void) +{ + gpio_set_direction(_pin, GPIO_MODE_OUTPUT); + gpio_set_level(_pin, 0); + esp_delay_us(TIME_SLOT_START_DURATION); + gpio_set_level(_pin, 1); + gpio_set_direction(_pin, GPIO_MODE_INPUT); + esp_delay_us(VALID_DATA_DURATION - TIME_SLOT_START_DURATION); + uint8_t bit = gpio_get_level(_pin); + esp_delay_us(TIME_SLOT_DURATION - RECOVERY_DURATION - VALID_DATA_DURATION); + return bit; +} + +static void _send_bit(const uint8_t bit) +{ + gpio_set_direction(_pin, GPIO_MODE_OUTPUT); + gpio_set_level(_pin, 0); + if (bit == 0) + { + esp_delay_us(TIME_SLOT_DURATION); + gpio_set_level(_pin, 1); + gpio_set_direction(_pin, GPIO_MODE_INPUT); + esp_delay_us(RECOVERY_DURATION); + } + else + { + esp_delay_us(TIME_SLOT_START_DURATION); + gpio_set_level(_pin, 1); + gpio_set_direction(_pin, GPIO_MODE_INPUT); + esp_delay_us(TIME_SLOT_DURATION); + } +} \ No newline at end of file