STM32配置配置ETH MAC的参数

在STM32中配置ETH MAC的参数需要以下步骤：

1. 确定ETH MAC的工作模式，可以选择MII或RMII模式。

2. 配置ETH MAC的时钟源，可以选择外部时钟源或者内部PLL时钟源。

3. 配置PHY芯片的地址，使ETH MAC能够与PHY进行通信。

4. 配置ETH MAC的MAC地址，以便其他设备能够识别该设备。

5. 配置ETH MAC的传输参数，如最大传输单元、发送和接收缓冲区大小等。

6. 启动ETH MAC，使其能够开始工作。

以下是一个简单的示例代码，可以帮助你更好地了解如何在STM32中配置ETH MAC的参数：

#include "stm32f4xx.h"
#include "stm32f4xx_eth.h"

void ETH_Configuration(void)
{
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_ETH_MAC | RCC_AHB1Periph_ETH_MAC_Tx | RCC_AHB1Periph_ETH_MAC_Rx, ENABLE);

  ETH_DeInit();

  ETH_StructInit(&ETH_InitStructure);
  ETH_InitStructure.ETH_AutoNegotiation = ETH_AutoNegotiation_Enable;
  ETH_InitStructure.ETH_Speed = ETH_Speed_100M;
  ETH_InitStructure.ETH_Mode = ETH_Mode_FullDuplex;
  ETH_InitStructure.ETH_RetryTransmission = ETH_RetryTransmission_Disable;
  ETH_InitStructure.ETH_AutomaticPadCRCStrip = ETH_AutomaticPadCRCStrip_Disable;
  ETH_InitStructure.ETH_ReceiveAll = ETH_ReceiveAll_Enable;
  ETH_InitStructure.ETH_BroadcastFramesReception = ETH_BroadcastFramesReception_Enable;
  ETH_InitStructure.ETH_PromiscuousMode = ETH_PromiscuousMode_Disable;
  ETH_InitStructure.ETH_MulticastFramesFilter = ETH_MulticastFramesFilter_Perfect;
  ETH_InitStructure.ETH_UnicastFramesFilter = ETH_UnicastFramesFilter_Perfect;
  ETH_InitStructure.ETH_ChecksumOffload = ETH_ChecksumOffload_Enable;
  ETH_InitStructure.ETH_ReceiveBuffer = ETH_ReceiveBuffer_Ring;
  ETH_InitStructure.ETH_TransmitBuffer = ETH_TransmitBuffer_Ring;
  ETH_InitStructure.ETH_DMAArbitration = ETH_DMAArbitration_RoundRobin_RxTx_2_1;
  ETH_InitStructure.ETH_DropTCPIPChecksumErrorFrame = ETH_DropTCPIPChecksumErrorFrame_Enable;
  ETH_InitStructure.ETH_ReceiveThresholdControl = ETH_ReceiveThresholdControl_64Bytes;
  ETH_InitStructure.ETH_ForwardErrorFrames = ETH_ForwardErrorFrames_Disable;
  ETH_InitStructure.ETH_ForwardUndersizedGoodFrames = ETH_ForwardUndersizedGoodFrames_Disable;
  ETH_InitStructure.ETH_SecondFrameOperate = ETH_SecondFrameOperate_Enable;
  ETH_InitStructure.ETH_AddressAlignedBeats = ETH_AddressAlignedBeats_Enable;
  ETH_InitStructure.ETH_FixedBurst = ETH_FixedBurst_Enable;
  ETH_InitStructure.ETH_RxDMABurstLength = ETH_RxDMABurstLength_32Beat;
  ETH_InitStructure.ETH_TxDMABurstLength = ETH_TxDMABurstLength_32Beat;
  ETH_InitStructure.ETH_RxDescAligned = ETH_RxDescAligned_Enable;
  ETH_InitStructure.ETH_TxDescAligned = ETH_TxDescAligned_Enable;

  while (ETH_Init(&ETH_InitStructure, PHY_ADDRESS) != ETH_SUCCESS);

  ETH_DMAITConfig(ETH_DMA_IT_NIS | ETH_DMA_IT_R, ENABLE);

  NVIC_InitTypeDef NVIC_InitStructure;
  NVIC_InitStructure.NVIC_IRQChannel = ETH_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}

在上面的代码中，我们首先开启了ETH MAC和相关的外设时钟，并使用ETH_DeInit函数将ETH MAC的所有寄存器恢复到默认值。然后，我们使用ETH_StructInit函数初始化了ETH_InitStructure结构体，并设置了各种ETH MAC参数。最后，我们使用ETH_Init函数将ETH MAC初始化，并使用ETH_DMAITConfig函数和NVIC_Init函数配置相关的DMA和中断。