请教：LWIP如何发送大于TCP_MSS（1460）的数据

发布于 2016-02-15 16:31:07 浏览：4210 订阅该版

RTT版本为1.2.1
在我的项目中调用lwip_send()函数发送数据。
当数据小于TCP_MSS时，一切正常;
当数据大于TCP_MSS时，lwip_send没有反馈错误信息，但是接受端始终没有数据。
我调试一直追踪到tcp_write函数都没有错误反馈，有没有找到问题出在哪？这个问题我已经调试好几天了还是无果。
打开TCP_OUTPUT_DEBUG调试后，在终端得到了以下信息

```
> 
tcp_write(pcb=20004f34, data=20009aa4, len=1466, apiflags=1)
tcp_write: queueing 6517:7977
tcp_write: queueing 7977:7983
tcp_output_segment: 6517:7977
tcp_output: sending ACK for 333009266
tcp_output_segment: 6517:7977
```

请哪位大侠指点一下，是否我的配置哪里有问题？还是其他什么情况。

以下是rtconfig.h配置

```c
/* RT-Thread config file */
#ifndef __RTTHREAD_CFG_H__
#define __RTTHREAD_CFG_H__
/* RT_NAME_MAX*/
#define RT_NAME_MAX	8

/* RT_ALIGN_SIZE*/
#define RT_ALIGN_SIZE	4

/* PRIORITY_MAX */
#define RT_THREAD_PRIORITY_MAX	32

/* Tick per Second */
#define RT_TICK_PER_SECOND	100

/* SECTION: RT_DEBUG */
/* Thread Debug */
#define RT_DEBUG
#define RT_THREAD_DEBUG

#define RT_USING_OVERFLOW_CHECK

/* Using Hook */
#define RT_USING_HOOK

/* Using Software Timer */
/* #define RT_USING_TIMER_SOFT */
#define RT_TIMER_THREAD_PRIO		4
#define RT_TIMER_THREAD_STACK_SIZE	512
#define RT_TIMER_TICK_PER_SECOND	10

/* SECTION: IPC */
/* Using Semaphore*/
#define RT_USING_SEMAPHORE

/* Using Mutex */
#define RT_USING_MUTEX

/* Using Event */
#define RT_USING_EVENT

/* Using MailBox */
#define RT_USING_MAILBOX

/* Using Message Queue */
#define RT_USING_MESSAGEQUEUE

/* SECTION: Memory Management */
/* Using Memory Pool Management*/
#define RT_USING_MEMPOOL

/* Using Dynamic Heap Management */
#define RT_USING_HEAP

/* Using Small MM */
#define RT_USING_SMALL_MEM

// <bool name="RT_USING_COMPONENTS_INIT" description="Using RT-Thread components initialization" default="true" />
#define RT_USING_COMPONENTS_INIT

/* SECTION: Device System */
/* Using Device System */
#define RT_USING_DEVICE
// <bool name="RT_USING_DEVICE_IPC" description="Using device communication" default="true" />
#define RT_USING_DEVICE_IPC

// <bool name="RT_USING_SERIAL" description="Using Serial" default="true" />
#define RT_USING_SERIAL
#define RT_USING_UART1
#define RT_USING_UART2
#define RT_USING_UART3

#define RT_USING_RTC

/* SECTION: Console options */
#define RT_USING_CONSOLE
/* the buffer size of console*/
#define RT_CONSOLEBUF_SIZE	        128
// <string name="RT_CONSOLE_DEVICE_NAME" description="The device name for console" default="uart1" />
//#define RT_CONSOLE_DEVICE_NAME	    "uart1"

/* SECTION: finsh, a C-Express shell */
#define RT_USING_FINSH
/* Using symbol table */
#define FINSH_USING_SYMTAB
#define FINSH_USING_DESCRIPTION

/* SECTION: device filesystem */
#define RT_USING_DFS

#define RT_USING_DFS_ELMFAT
/* Reentrancy (thread safe) of the FatFs module.  */
#define RT_DFS_ELM_REENTRANT
/* Number of volumes (logical drives) to be used. */
#define RT_DFS_ELM_DRIVES			2
/* #define RT_DFS_ELM_USE_LFN			1 */
/* #define RT_DFS_ELM_CODE_PAGE			936 */
#define RT_DFS_ELM_MAX_LFN			255
/* Maximum sector size to be handled. */
#define RT_DFS_ELM_MAX_SECTOR_SIZE  4096

/* the max number of mounted filesystem */
#define DFS_FILESYSTEMS_MAX			2
/* the max number of opened files 		*/
#define DFS_FD_MAX					4

/* SECTION: lwip, a lighwight TCP/IP protocol stack */
#define RT_USING_LWIP
/* LwIP uses RT-Thread Memory Management */
#define RT_LWIP_USING_RT_MEM
/* Enable ICMP protocol*/
#define RT_LWIP_ICMP
/* Enable UDP protocol*/
#define RT_LWIP_UDP
/* Enable TCP protocol*/
#define RT_LWIP_TCP
/* Enable DNS */
#define RT_LWIP_DNS

/* the number of simulatenously active TCP connections*/
#define RT_LWIP_TCP_PCB_NUM	5

/* Using DHCP */
#define RT_LWIP_DHCP

/* ip address of target*/
#define RT_LWIP_IPADDR0	192
#define RT_LWIP_IPADDR1	168
#define RT_LWIP_IPADDR2	1
#define RT_LWIP_IPADDR3	30

/* gateway address of target*/
#define RT_LWIP_GWADDR0	192
#define RT_LWIP_GWADDR1	168
#define RT_LWIP_GWADDR2	1
#define RT_LWIP_GWADDR3	1

/* mask address of target*/
#define RT_LWIP_MSKADDR0	255
#define RT_LWIP_MSKADDR1	255
#define RT_LWIP_MSKADDR2	255
#define RT_LWIP_MSKADDR3	0

/* tcp thread options */
#define RT_LWIP_TCPTHREAD_PRIORITY		12
#define RT_LWIP_TCPTHREAD_MBOX_SIZE		10
#define RT_LWIP_TCPTHREAD_STACKSIZE		1024

/* ethernet if thread options */
#define RT_LWIP_ETHTHREAD_PRIORITY		15
#define RT_LWIP_ETHTHREAD_MBOX_SIZE		10
#define RT_LWIP_ETHTHREAD_STACKSIZE		512

/* TCP sender buffer space */
#define RT_LWIP_TCP_SND_BUF	8192
/* TCP receive window. */
#define RT_LWIP_TCP_WND		8192

/* SECTION: RT-Thread/GUI */
/* #define RT_USING_RTGUI */

/* name length of RTGUI object */
#define RTGUI_NAME_MAX		12
/* support 16 weight font */
#define RTGUI_USING_FONT16
/* support Chinese font */
#define RTGUI_USING_FONTHZ
/* use DFS as file interface */
#define RTGUI_USING_DFS_FILERW
/* use font file as Chinese font */
#define RTGUI_USING_HZ_FILE
/* use Chinese bitmap font */
#define RTGUI_USING_HZ_BMP
/* use small size in RTGUI */
#define RTGUI_USING_SMALL_SIZE
/* use mouse cursor */
/* #define RTGUI_USING_MOUSE_CURSOR */
/* default font size in RTGUI */
#define RTGUI_DEFAULT_FONT_SIZE	16

/* image support */
/* #define RTGUI_IMAGE_XPM */
/* #define RTGUI_IMAGE_BMP */

// <bool name="RT_USING_CMSIS_OS" description="Using CMSIS OS API" default="true" />
// #define RT_USING_CMSIS_OS
// <bool name="RT_USING_RTT_CMSIS" description="Using CMSIS in RTT" default="true" />
#define RT_USING_RTT_CMSIS
// <bool name="RT_USING_BSP_CMSIS" description="Using CMSIS in BSP" default="true" />
// #define RT_USING_BSP_CMSIS

#endif
```