#include "stm32f4xx.h"
#include "hardware.h"

uint8_t ModbusRxBuf[MODBUS_RX_BUF_SIZE];
uint16_t ModbusRxLen = 0;

void ModbusGpioInit(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_USART1);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_USART1);
}

void ModbusUsartInit(void)
{
    USART_InitTypeDef USART_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
  
    USART_InitStructure.USART_BaudRate = MODBUS_USART_BAUDRATE;
    USART_InitStructure.USART_WordLength = USART_WordLength_8b;
    USART_InitStructure.USART_StopBits = USART_StopBits_1;
    USART_InitStructure.USART_Parity = USART_Parity_No; 
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
    USART_Init(USART1, &USART_InitStructure);

    USART_ITConfig(USART1, USART_IT_IDLE, ENABLE);
    USART_Cmd(USART1, ENABLE);
}

void ModbusDmaInit(void)
{
    DMA_InitTypeDef DMA_InitStructure;

    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);

    /* DMA2_Stream2 用于 USART1_RX */
    DMA_DeInit(DMA2_Stream2);
    DMA_InitStructure.DMA_Channel = DMA_Channel_4;
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART1->DR);
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)ModbusRxBuf;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
    DMA_InitStructure.DMA_BufferSize = MODBUS_RX_BUF_SIZE;
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
    DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
    DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
    DMA_InitStructure.DMA_Priority = DMA_Priority_High;
    DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
    DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull;
    DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
    DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
    DMA_Init(DMA2_Stream2, &DMA_InitStructure);

    /* DMA2_Stream7 用于 USART1_TX */
    DMA_DeInit(DMA2_Stream7);
    DMA_InitStructure.DMA_Channel = DMA_Channel_4;
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(USART1->DR);
    DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
    DMA_Init(DMA2_Stream7, &DMA_InitStructure);

    /* 使能USART的DMA请求 */
    USART_DMACmd(USART1, USART_DMAReq_Rx | USART_DMAReq_Tx, ENABLE);
    DMA_Cmd(DMA2_Stream2, ENABLE);
}

void ModbusNvicInit(void)
{
    NVIC_InitTypeDef NVIC_InitStructure;

    NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 5; 
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}


void MdobusHardwareInit(void)
{
    ModbusGpioInit();
    ModbusUsartInit();
    ModbusDmaInit();
    ModbusNvicInit();
}