#include "modbus_rec_send.h"


/*USART接收空闲中断*/
void USART1_IRQHandler(void)
{
    uint32_t temp;
    uint16_t rxLenRemain;

    OSIntEnter();   /*进入中断*/
    if(USART_GetITStatus(USART1, USART_IT_IDLE) == SET)
    {
        /*清除IDLE中断标志位*/
        temp = USART1->SR;
        temp = USART1->DR;
        (void)temp;

        /*判断是否接收到帧，触发TIM计时*/
        rxLenRemain = DMA_GetCurrDataCounter(DMA2_Stream2);
        if(rxLenRemain != MODBUS_RX_BUF_SIZE)
        {
            /*启动TIM计时*/
            TIM_Cmd(TIM5, DISABLE);
            TIM_SetCounter(TIM5, 0);        /*清除计数值*/
            //TIM_ClearITPendingBit(TIM5, TIM_IT_Update);     /*清除中断标志位*/
            TIM_Cmd(TIM5, ENABLE);
        }
    }
    OSIntExit();    /*退出中断*/
}

/*TIM定时器中断*/
void TIM5_IRQHandler(void)
{
    uint16_t rxLenRemain;

    OSIntEnter();
    if (TIM_GetITStatus(TIM5, TIM_IT_Update) != RESET)
    {
        /*清除TIM5更新中断标志*/
        TIM_ClearITPendingBit(TIM5, TIM_IT_Update);

        /*关闭DMA*/
        DMA_Cmd(DMA2_Stream2, DISABLE);
        /*清除传输已经完成TCIF2、传输已经完成一半HTIF2标志位*/
        DMA_ClearFlag(DMA2_Stream2, DMA_FLAG_TCIF2 | DMA_FLAG_HTIF2);

        /*计算数据长度*/
        rxLenRemain = DMA_GetCurrDataCounter(DMA2_Stream2);
        ModbusRxLen = MODBUS_RX_BUF_SIZE - rxLenRemain;

        /*释放接收到数据帧信号量，唤醒帧解析任务*/
        if(ModbusRxLen >= 4)    /*4字节（1字节地址、1字节功能、2字节CRC）*/
        {
            OSSemPost(ModbusReceived);
        }

        /*重新指定接收地址*/
        DMA_MemoryTargetConfig(DMA2_Stream2, (uint32_t)ModbusRxBuf, DMA_Memory_0);
        /*重启DMA*/
        DMA_SetCurrDataCounter(DMA2_Stream2, MODBUS_RX_BUF_SIZE);
        DMA_Cmd(DMA2_Stream2, ENABLE);
    }
    OSIntExit();
}

/*modbus响应帧发送*/
void ModbusSend(uint8_t *txBuf, uint16_t len)
{
    if(DMA_GetCmdStatus(DMA2_Stream7) == ENABLE)
    {
        /*等待DMA发送完成*/
        while(DMA_GetFlagStatus(DMA2_Stream7, DMA_FLAG_TCIF7) == RESET);
    }

    /*先关闭DMA发送通道*/
    DMA_Cmd(DMA2_Stream7, DISABLE);

    /*等待DMA关闭*/
    while (DMA_GetCmdStatus(DMA2_Stream7) != DISABLE); 

    /*清除传输已经完成TCIF7、传输已经完成一半HTIF7、FIFO错误FEIF7标志位*/
    DMA_ClearFlag(DMA2_Stream7, DMA_FLAG_FEIF7 | DMA_FLAG_HTIF7 | DMA_FLAG_TCIF7);
    
    /*配置发送地址和长度*/
    DMA_MemoryTargetConfig(DMA2_Stream7, (uint32_t)txBuf, DMA_Memory_0);     
    DMA_SetCurrDataCounter(DMA2_Stream7, len);

    /*等待串口发送完成*/
    while (USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET);
    
    /*启动 DMA 发送*/
    DMA_Cmd(DMA2_Stream7, ENABLE);
}

/*crc16校验*/
uint16_t Crc16(const uint8_t *data, uint16_t length)
{
    uint16_t crc;
    uint16_t byteInd;
    uint8_t bitInd;
    
    crc = 0xFFFFu;
    for (byteInd = 0u; byteInd < length; byteInd++)
    {
        crc ^= (uint16_t)data[byteInd];
        for (bitInd = 0u; bitInd < 8u; bitInd++)
        {
            if ((crc & 0x0001u) != 0u)
            {
                crc >>= 1;
                crc ^= 0xA001u;
            }
            else
            {
                crc >>= 1;
            }
        }
    }
    return crc;
}

/*crc16检查*/
int8_t ChcekCrc16(uint16_t recCrc16, uint8_t *data, uint16_t length)
{
    uint16_t crc16 = Crc16(data, (length - 2));

    if(recCrc16 == crc16)
    {
        return 0;
    }
    else
    {
        return -1;
    }
}

void AddCrc16(uint8_t *data, uint16_t length)
{
    uint8_t *dataT = data;
    uint16_t crc16 = Crc16(data, length);

    /*低前高后*/
    dataT[length] = (uint8_t)(crc16 & 0x00FF);
    dataT[length + 1] = (uint8_t)(crc16 >> 8);
}