I am trying to read a DS18B20 temperature sensor with I2C. I use a DS2484 driver to convert the I2C signals to a 1-Wire signal.
I have the following code:
/* Includes ------------------------------------------------------------------*/ #include "stm32l1xx_hal.h" /* USER CODE BEGIN Includes */ /* USER CODE END Includes */ /* Private variables ---------------------------------------------------------*/ I2C_HandleTypeDef hi2c2; RTC_HandleTypeDef hrtc; /* USER CODE BEGIN PV */ /* Private variables ---------------------------------------------------------*/ /* USER CODE END PV */ /* Private function prototypes -----------------------------------------------*/ void SystemClock_Config(void); static void MX_GPIO_Init(void); static void MX_I2C2_Init(void); static void MX_RTC_Init(void); /* USER CODE BEGIN PFP */ /* Private function prototypes -----------------------------------------------*/ void ow_setup_ds2484(void); /* USER CODE END PFP */ /* USER CODE BEGIN 0 */ // I2C test // uint8_t dummy_data[2] = {0}; // HAL_I2C_Master_Transmit (&hi2c2, 0x10, &dummy_data[0], 2, 1000); // 1sec timeout uint8_t byte_array[6]; byte_array[0] = 0xE1; /* Data 0 */ byte_array[1] = 0xC3; /* Data 1 */ byte_array[2] = 0xD2; /* Data 2 */ byte_array[3] = 0xEE; /* Data 3 */ // byte_array[4] = 0x00; /* Data 4 */ uint8_t dummy_data[25] = {0xF0, // reset 0x01, //byte om data mee in te kunnen lezen 0xD2,//WCFG 0x22}; uint8_t dummy_data1[25] = { 0x22}; HAL_I2C_Master_Transmit (&hi2c2, 0x30, &dummy_data[0], 1, 1000); // reset device HAL_I2C_Master_Receive(&hi2c2, 0x31, &dummy_data[1] , 1, 1000); // lees byte in na reset HAL_I2C_Master_Transmit (&hi2c2, 0x30, byte_array, 2, 1000); // set read pointer HAL_I2C_Master_Transmit (&hi2c2, 0x30, &dummy_data[2], 1, 1000); // configureer HAL_I2C_Master_Receive(&hi2c2, 0x31, &dummy_data[1] , 1, 1000); // lees byte in na configureren /* USER CODE END 0 */ int main(void) { / HAL_Init(); /* Configure the system clock */ SystemClock_Config(); /* Initialize all configured peripherals */ MX_GPIO_Init(); MX_I2C2_Init(); MX_RTC_Init(); ow_setup_ds2484(); /* USER CODE BEGIN 2 */ /* USER CODE END 2 */ /* Infinite loop */ /* USER CODE BEGIN WHILE */ while (1) { /* USER CODE END WHILE */ // --- toggle PC4 ---// HAL_GPIO_WritePin (GPIOC,GPIO_PIN_9,GPIO_PIN_SET); // enable pin (vcc) HAL_Delay (100); HAL_GPIO_WritePin (GPIOC,GPIO_PIN_9,GPIO_PIN_RESET); // disable pin (0v) HAL_Delay (100); } // while } // main void ow_setup_ds2484(void) { }
I followed the explanation of the datasheet:
Device Reset (After Power-Up) S AD,0 A DRST A Sr AD,1 A <byte> A\ P Activities that are underlined denote an optional read access to verify the success of the command. Set Read Pointer (To Read from Another Register) Case A: Valid Read Pointer Code S AD,0 A SRP A C3h A P C3h is the read pointer code for the Device Configuration register. Case B: Invalid Read Pointer Code S AD,0 A SRP A E5h A\ P E5h is an invalid read pointer code. Write Device Configuration (Before Starting 1-Wire Activity) Case A: 1-Wire Idle (1WB = 0) S AD,0 A WCFG A <byte> A Sr AD,1 A <byte> A\ P Activities that are underlined denote an optional read access to verify the success of the command. Case B: 1-Wire Busy (1WB = 1) S AD,0 A WCFG A\ P The master should stop and restart as soon as the DS2484 does not acknowledge the command code. Adjust 1-Wire Port (after power-up, e.g., to select a 1-Wire timing other than the default) Case A: 1-Wire Idle (1WB = 0) Repeat to set additional port parameters S AD,0 A ADJP A <byte> A <byte> A P
However, I still don't know what to do next to read the DS18B20 sensor. Plese help me :)
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