[参考译文] TM4C1294NCPDT：TM4C1294NCPDT

您好！

我使用 Tivaware 用户指南中提供的示例修改了 UIP 代码部分。 但是、如果您看到用户指南中的代码部分、则缓冲区的 TX 和 RX 互换存在很小(但有问题)的错误、如下图所示。  

我更正了这个 TX 和 RX 的互换。 即使这样、它也无法接收和传输数据包。 但是当我选中"Debug"时、分配了12个缓冲区、如之前的回复中所示。 我将附加缓冲区的代码部分和描述符初始化。  

//*****************************************************************************
//
// Ethernet DMA descriptors.
//
// The MAC hardware needs a minimum of 3 receive descriptors to operate. The
// number used will be application-dependent and should be tuned for best
// performance.
//
//*****************************************************************************
#define NUM_TX_DESCRIPTORS 3
#define NUM_RX_DESCRIPTORS 24
tEMACDMADescriptor g_psRxDescriptor[NUM_RX_DESCRIPTORS];
tEMACDMADescriptor g_psTxDescriptor[NUM_TX_DESCRIPTORS];
uint32_t g_ui32RxDescIndex;
uint32_t g_ui32TxDescIndex;

#define RX_BUFFER_SIZE 1536
uint8_t g_ppui8RxBuffer[NUM_RX_DESCRIPTORS][RX_BUFFER_SIZE];



void
InitDescriptors(uint32_t ui32Base)
{
		uint32_t ui32Loop;
	
		// Initialize each of the transmit descriptors. Note that we leave the
		// buffer pointer and size empty and the OWN bit clear here since we have
		// not set up any transmissions yet.
		//
		for(ui32Loop = 0; ui32Loop < NUM_TX_DESCRIPTORS; ui32Loop++) {
			g_psTxDescriptor[ui32Loop].ui32Count = DES1_TX_CTRL_SADDR_INSERT;
			g_psTxDescriptor[ui32Loop].DES3.pLink = (ui32Loop == (NUM_TX_DESCRIPTORS - 1)) ?
											g_psTxDescriptor : &g_psTxDescriptor[ui32Loop + 1];
			g_psTxDescriptor[ui32Loop].ui32CtrlStatus = (DES0_TX_CTRL_LAST_SEG | DES0_TX_CTRL_FIRST_SEG |
					DES0_TX_CTRL_INTERRUPT | DES0_TX_CTRL_CHAINED |
					DES0_TX_CTRL_IP_HDR_CHKSUM);
		}
		//
		// Initialize each of the receive descriptors. We clear the OWN bit here
		// to make sure that the receiver doesn t start writing anything
		// immediately.
		//
		for(ui32Loop = 0; ui32Loop < NUM_RX_DESCRIPTORS; ui32Loop++)
		{
		g_psRxDescriptor[ui32Loop].ui32CtrlStatus = 0;
		g_psRxDescriptor[ui32Loop].ui32Count = (DES1_RX_CTRL_CHAINED |
										(RX_BUFFER_SIZE << DES1_RX_CTRL_BUFF1_SIZE_S));
		g_psRxDescriptor[ui32Loop].pvBuffer1 = g_ppui8RxBuffer[ui32Loop];
		g_psRxDescriptor[ui32Loop].DES3.pLink = (ui32Loop == (NUM_RX_DESCRIPTORS - 1)) ?
					g_psRxDescriptor : &g_psRxDescriptor[ui32Loop + 1];
		}
		//
		// Set the descriptor pointers in the hardware.
		//
		EMACRxDMADescriptorListSet(ui32Base, g_psRxDescriptor);
		EMACTxDMADescriptorListSet(ui32Base, g_psTxDescriptor);
		//
		// Start from the beginning of both descriptor chains. We actually set
		// the transmit descriptor index to the last descriptor in the chain
		// since it will be incremented before use and this means the first
		// transmission we perform will use the correct descriptor.
		//
		g_ui32RxDescIndex = 0;
		g_ui32TxDescIndex = NUM_TX_DESCRIPTORS - 1;
}

然后、我将 emac.c 和 emac.h 复制到我的源代码文件夹中、并将这些文件添加到我的项目中。 然后进行编译和下载。 令人惊讶的是它能起作用  

感谢您的支持。