/** *! * \file b_drv_ds18b20.c * \version v0.0.1 * \date 2021/04/29 * \author polyGithub(baoli.chen@outlook.com) ******************************************************************************* * @attention * * Copyright (c) 2021 polyGithub * * 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. ******************************************************************************* */ /*Includes ----------------------------------------------*/ #include "drivers/inc/b_drv_ds18b20.h" #include <string.h> /** * \addtogroup B_DRIVER * \{ */ /** * \addtogroup DS18B20 * \{ */ /** * \defgroup DS18B20_Private_TypesDefinitions * \{ */ /** * \} */ /** * \defgroup DS18B20_Private_Defines * \{ */ #define DRIVER_NAME DS18B20 /** * \} */ /** * \defgroup DS18B20_Private_Macros * \{ */ /** * \} */ /** * \defgroup DS18B20_Private_Variables * \{ */ bDRIVER_HALIF_TABLE(bDS18B20_HalIf_t, DRIVER_NAME); /** * \} */ /** * \defgroup DS18B20_Private_FunctionPrototypes * \{ */ /** * \} */ /** * \defgroup DS18B20_Private_Functions * \{ */ static uint8_t _bSbusReady(bDriverInterface_t *pdrv) { uint16_t cp = 0; uint8_t retval = 1; bDRIVER_GET_HALIF(_if, bDS18B20_HalIf_t, pdrv); bHalGpioWritePin(_if->port, _if->pin, 0); bHalDelayUs(600); // 480~960us bHalGpioWritePin(_if->port, _if->pin, 1); bHalGpioConfig(_if->port, _if->pin, B_HAL_GPIO_INPUT, B_HAL_GPIO_NOPULL); cp = 0; while (((bHalGpioReadPin(_if->port, _if->pin)) == 1) && (cp++ < 100)) { bHalDelayUs(1); } if (cp >= 100) { retval = 0; } bHalDelayUs(250); // 60~240us bHalGpioConfig(_if->port, _if->pin, B_HAL_GPIO_OUTPUT, B_HAL_GPIO_NOPULL); bHalGpioWritePin(_if->port, _if->pin, 1); return retval; } static uint8_t _bSbusReadByte(bDriverInterface_t *pdrv) { uint8_t byte = 0; uint8_t bit = 0; uint8_t i; bDRIVER_GET_HALIF(_if, bDS18B20_HalIf_t, pdrv); for (i = 0; i < 8; i++) { bHalGpioWritePin(_if->port, _if->pin, 0); bHalDelayUs(2); bHalGpioWritePin(_if->port, _if->pin, 1); bHalGpioConfig(_if->port, _if->pin, B_HAL_GPIO_INPUT, B_HAL_GPIO_NOPULL); bHalDelayUs(2); // < 15us bit = bHalGpioReadPin(_if->port, _if->pin); byte = (byte >> 1) | (bit << 7); bHalDelayUs(100); // > 60us bHalGpioConfig(_if->port, _if->pin, B_HAL_GPIO_OUTPUT, B_HAL_GPIO_NOPULL); bHalGpioWritePin(_if->port, _if->pin, 1); } return byte; } static void _bSbusWriteByte(bDriverInterface_t *pdrv, uint8_t dat) { uint8_t j, wbit = 0; bDRIVER_GET_HALIF(_if, bDS18B20_HalIf_t, pdrv); for (j = 0; j < 8; j++) { wbit = dat & 0x1; dat >>= 1; bHalGpioWritePin(_if->port, _if->pin, 0); bHalDelayUs(2); bHalGpioWritePin(_if->port, _if->pin, wbit); bHalDelayUs(100); // 60~120us bHalGpioWritePin(_if->port, _if->pin, 1); bHalDelayUs(2); } } static int _bDS18B20Start(bDriverInterface_t *pdrv) { int retval = -1; if (_bSbusReady(pdrv)) { _bSbusWriteByte(pdrv, 0xCC); _bSbusWriteByte(pdrv, 0x44); retval = 0; } return retval; } static int _bDS18B20Read(bDriverInterface_t *pdrv, uint32_t off, uint8_t *pbuf, uint32_t len) { int16_t temp_dig = 0; float temp = 0; uint8_t tmh, tml; bTempVal_t temp_val; if (len < sizeof(bTempVal_t)) { return -1; } if (pdrv->_private.v == 0) { _bDS18B20Start(pdrv); pdrv->_private.v = bHalGetSysTick(); return -1; } else if (TICK_DIFF_BIT32(pdrv->_private.v, bHalGetSysTick()) < MS2TICKS(500)) { return -2; } if (_bSbusReady(pdrv)) { _bSbusWriteByte(pdrv, 0xCC); _bSbusWriteByte(pdrv, 0xBE); } else { return -1; } pdrv->_private.v = 0; tml = _bSbusReadByte(pdrv); tmh = _bSbusReadByte(pdrv); temp_dig = ((int16_t)tmh) << 8; temp_dig |= tml; if (temp_dig < 0) { temp = (~temp_dig + 1) * 0.0625; } else { temp = temp_dig * 0.0625; } temp_val.tempx100 = (int16_t)(temp * 100); memcpy(pbuf, &temp_val, sizeof(bTempVal_t)); return sizeof(bTempVal_t); } /** * \} */ /** * \addtogroup DS18B20_Exported_Functions * \{ */ int bDS18B20_Init(bDriverInterface_t *pdrv) { bDRIVER_STRUCT_INIT(pdrv, DRIVER_NAME, bDS18B20_Init); pdrv->read = _bDS18B20Read; pdrv->_private.v = 0; return 0; } #ifdef BSECTION_NEED_PRAGMA #pragma section driver_init #endif bDRIVER_REG_INIT(B_DRIVER_DS18B20, bDS18B20_Init); #ifdef BSECTION_NEED_PRAGMA #pragma section #endif /** * \} */ /** * \} */ /** * \} */ /************************ Copyright (c) 2021 polyGithub *****END OF FILE****/