dmx.h

/* 
 * This file is part of the ESP32-DMX distribution (https://github.com/luksal/ESP32-DMX).
 * Copyright (c) 2021 Lukas Salomon.
 * 
 * This program is free software: you can redistribute it and/or modify  
 * it under the terms of the GNU General Public License as published by  
 * the Free Software Foundation, version 3.
 *
 * This program is distributed in the hope that it will be useful, but 
 * WITHOUT ANY WARRANTY; without even the implied warranty of 
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License 
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdint.h>
#include <string.h>

#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"
#include "driver/uart.h"

#ifndef DMX_h
#define DMX_h

enum DMXDirection { input, output };
enum DMXState { DMX_IDLE, DMX_BREAK, DMX_DATA, DMX_OUTPUT };

class DMX
{
    public:
        static void Initialize(DMXDirection direction);     // initialize library

        static uint8_t Read(uint16_t channel);              // returns the dmx value for the givven address (values from 1 to 512)

        static void ReadAll(uint8_t * data, uint16_t start, size_t size);   // copies the defined channels from the read buffer

        static void Write(uint16_t channel, uint8_t value); // writes the dmx value to the buffer
        
        static void WriteAll(uint8_t * data, uint16_t start, size_t size);  // copies the defined channels into the write buffer
        static void WriteAllValue(uint8_t value, uint16_t start, size_t size);

        static uint8_t IsHealthy();                            // returns true, when a valid DMX signal was received within the last 500ms
        
    private:
        DMX();                                              // hide constructor

        static QueueHandle_t dmx_rx_queue;                  // queue for uart rx events
        
        static SemaphoreHandle_t sync_dmx;                  // semaphore for syncronising access to dmx array

        static DMXState dmx_state;                           // status, in which recevied state we are

        static uint16_t current_rx_addr;                    // last received dmx channel

        static long last_dmx_packet;                        // timestamp for the last received packet

        static uint8_t dmx_data[513];                       // stores the received dmx data

        static void uart_event_task(void *pvParameters);    // event task

        static void uart_send_task(void*pvParameters);      // transmit task
};

#endif