#ifndef _FLUX_UART_H
#define _FLUX_UART_H

#ifdef __cplusplus
extern "C" {
#endif

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/uart.h"
#include "driver/gpio.h"
#include "sdkconfig.h"
#include "esp_log.h"


/* UART */
/* UART1 RT-2 TX-1*/
/* UART2 RT-46 TX-45*/
#define ECHO_TEST_TXD2 GPIO_NUM_45
#define ECHO_TEST_RXD2 GPIO_NUM_46
#define ECHO_UART_PORT_NUM2      (UART_NUM_2)

#define ECHO_TEST_TXD1 GPIO_NUM_1
#define ECHO_TEST_RXD1 GPIO_NUM_2
#define ECHO_UART_PORT_NUM1      (UART_NUM_1)

#define ECHO_TEST_RTS (UART_PIN_NO_CHANGE)
#define ECHO_TEST_CTS (UART_PIN_NO_CHANGE)

#define ECHO_UART_BAUD_RATE     (9600)
#define ECHO_TASK_STACK_SIZE    (16*1024)

/* Choose whether to use big-endian or little-endian. Modbus-RTU communication uses little-endian. */
#define BIG_ENDIAN_USED  0
#define LITTLE_ENDIAN_USED  !BIG_ENDIAN_USED

/* Digital flow meter address */
#define FLUX_ADDR 0x01
#define FLUX_FUNC_READ 0x03
#define FLUX_FUNC_SET 0x16

/* Modbus-RTU frame format */
/* All data from the wet flow meter are two bytes long */
/*
    ADDR : 1byte
    FUNC : 1byte
    DATA : 2byte
    CRC : 2byte
*/
struct ModbusRTU_Frame
{
    unsigned char ADDR;
    unsigned char FUNC;
    unsigned char DATA[4];
    unsigned char CRC[2];
};

extern struct ModbusRTU_Frame flux_frame;
extern struct ModbusRTU_Frame breath_frame;

/* UART1 response task */
void uart1_echoTask(void* arg);

/* UART2 response task */
void uart2_echoTask(void* arg);

/* CRC16 checksum */
unsigned short CRC16(unsigned char* pchMsg, unsigned short wDataLen);


esp_err_t ModbusRTU_Send(uart_port_t uart_num, struct ModbusRTU_Frame *frame);



#ifdef __cplusplus
} /*extern "C"*/
#endif

#endif