main/task_ds18b20.h


/**
 * @file task_ds18b20.h
 * @brief The FreeRTOS task to query the DS18B20 sensors on one or two
 *        one-wire busses. Each bus must have only one sensor. That way
 *        we don't need to care about the DS18B20 internal ROM address.
 *        The task will update the DS18B20_State structure.
 */

#ifndef	_TASK_DS18B20_H
#define	_TASK_DS18B20_H

/*
 * Error codes in this task
 */
#define	DS18B20_ERR_NONE		0			///< No errors
#define	DS18B20_ERR_CRC			1			///< CRC read error
#define	DS18B20_ERR_READ		2			///< Generic read error

#define	DS18B20_MAX			4			///< Maximum number of DS18B20 sensors.

/**
 * @brief Structure for a temperature sensor.
 */
typedef struct strTempsensor {
    double      temperature;            	///< Current temperature.
    char        rom_code[17];           	///< ROM code of this device.
    int         error;                  	///< Error number.
} tempsensor_t;


/**
 * @brief Structure containing the variables for the DS18B20 task.
 */
typedef struct {
    bool		valid;			///< Sensor valid reading.
    int			num_sensors;		///< Number of sensors
    tempsensor_t	sensor[DS18B20_MAX];	///< Temperature sensors
} DS18B20_State;


/**
 * @brief Request a new measurement
 */
void request_ds18b20(void);


/**
 * @brief Measurement ready state
 * @return Returns true if the temperature measurements are ready
 */
bool ready_ds18b20(void);


/**
 * @brief The FreeRTOS task to update the DS18B20 temperature sensors on request.
 * @param pvParameters Parameters for the task.
 */
void task_ds18b20(void *pvParameters);


#endif