最近老板有个项目,其中要做一个Zigbee的无线接入点,即将ZigBee无线传感网络中的数据通过TCP/IP协议传输到以太网上。传统的这种无线接入点即网关都是上位机加下位机模式做成的,即主控芯片(如ARM)加无线模块(如cc2530),ARM与cc2530通过UARST通信,cc2530建立WSN网络,ARM与PC机通过TCP/IP通信,考虑到此系统的成本以及其中的数据传输量不大,就不用ARM,直接将cc2530做成网关,这就需要将TCP/IP协议栈移植到cc2530上,同时与ZigBee协议栈能很好的协同运行。
因为cc2530的FLASH有256K,Z-stack占用了大部分,所以要用TCP/IP,只能移植一个轻量型网络协议栈,现在比较流行的就是Adam Dunkels写的lwIP和uIP,还有Micrium的uc/IP,lwip和uc/ip所占空间较大,移植较为麻烦,所以就用uip。uip是一种免费可的极小的TCP/IP协议栈,主要实现了ARP,ICMP,TCP,UDP协议,在8位或16位单片机上用的较多,对rom和ram要求很少。
在网上看了一些uip移植到51或STM32的文章,同时也花了两天时间看了uip的实现源码,如果不熟悉TCP/IP协议的话读起来还是很吃力,所以先看看TCP/IP,建议看TCP/IP协议详解——卷一。看完之后大概知道移植过程了。
移植之前先要写网络芯片驱动程序,我用的是enc28j60,独立控制的SPI接口,因为cc2530的spi接口用来下载调试了,另一个spi被串口复用了,所以只用用GPIO模拟SPI。
写驱动程序之前认真读了enc28j60的datasheet,在网上也找到了相关的驱动程序,可以稍加修改拿来用。下面贴出spi程序和enc28j60的程序。
#include "spi.h"
void WriteByte(u8_t dat)
{
u8_t i;
for(i=0;i<8;i++)
{
SCKN = 0;
asm("nop");
if(dat&0x80)
{
SIN = 1;
}
else
SIN = 0;
dat <<= 1;
asm("nop");
SCKN = 1;
asm("nop");
}
SCKN=0; //空闲状态为低电平
}
u8_t ReadByte(void)
{
u8_t i,dat;
SCKN=0;
dat1=0;
for(i=0;i<8;i++)
{
SCKN=1;
dat1 <<=1;
dat1 |= SON;
SCKN=0;
}
return dat;
}
spi.h文件定义了与enc28j60spi接口的GPIO,
#ifndef SPI_H
#define SPI_H
#include <ioCC2530.h>
#define SON P0_5 // MISO
#define SIN P0_6 // MOSI
#define SCKN P0_7 // SCK
#define CSN P1_3 // 28J60-- CS
#define RESET P1_2 // Reset
void WriteByte(u8_t dat);
u8_t ReadByte(void);
#endif
enc28j60.c文件:
#include "enc28j60.h"
#include "spi.h"
#define MIN(a,b) (a) < (b) ? (a) : (b)
XDATA u8_t Enc28j60Bank;
XDATA u16_t NextPacketPtr;
void delay_100ns()
{
asm("nop");
asm("nop");
asm("nop");
}
void delay_ms(int t1)
{
int i;
while(t1--)
{
for(i=10;i;--i)
{
delay_100ns();
}
}
}
//*******************************************************************************************
//
// Function : enc28j60ReadOp
// Description :
//
//*******************************************************************************************
u8_t enc28j60ReadOp(u8_t op, u8_t address)
{
u8_t dat1;
// activate CS
CSN =0;
// issue read command
delay_100ns();
WriteByte(op | (address & ADDR_MASK));
dat1 = ReadByte();
// do dummy read if needed (for mac and mii, see datasheet page 29)
if(address & 0x80) dat1 = ReadByte();
// release CS
CSN=1;
return(dat1);
}
//*******************************************************************************************
//
// Function : enc28j60WriteOp
// Description :
//
//*******************************************************************************************
void enc28j60WriteOp(u8_t op, u8_t address, u8_t mydat)
{
CSN=0;
// issue write command
delay_100ns();
WriteByte( op | (address & ADDR_MASK));
// write data
WriteByte(mydat);
CSN=1;
delay_100ns();
}
//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************
void enc28j60SetBank(u8_t address)
{
// set the bank (if needed)
if((address & BANK_MASK) != Enc28j60Bank)
{
// set the bank
enc28j60WriteOp(ENC28J60_BIT_FIELD_CLR, ECON1, (ECON1_BSEL1|ECON1_BSEL0));
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, (address & BANK_MASK)>>5);
Enc28j60Bank = (address & BANK_MASK);
}
}
//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************
u8_t enc28j60Read(u8_t address)
{
// select bank to read
enc28j60SetBank(address);
// do the read
return enc28j60ReadOp(ENC28J60_READ_CTRL_REG, address);
}
//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************
void enc28j60Write(u8_t address, u8_t mydat)
{
// select bank to write
enc28j60SetBank(address);
// do the write
enc28j60WriteOp(ENC28J60_WRITE_CTRL_REG, address, mydat);
}
//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************
u16_t enc28j60_read_phyreg(u8_t address)
{
u16_t mydat;
// set the PHY register address
enc28j60Write(MIREGADR, address);
enc28j60Write(MICMD, MICMD_MIIRD);
// Loop to wait until the PHY register has been read through the MII
// This requires 10.24us
while( (enc28j60Read(MISTAT) & MISTAT_BUSY) );
// Stop reading 这里应该清零
//enc28j60Write(MICMD, MICMD_MIIRD);
enc28j60Write(MICMD, 0x0);
// Obtain results and return
mydat = enc28j60Read ( MIRDL );
//PrintHex(mydat);
//mydat |= enc28j60Read ( MIRDH ); //此地方源代码有误 改成
mydat |= (enc28j60Read ( MIRDH )<<8);
// PrintHex(mydat);
return mydat;
}
//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************
void enc28j60PhyWrite(u8_t address, u16_t mydat)
{
// set the PHY register address
enc28j60Write(MIREGADR, address);
// write the PHY data
enc28j60Write(MIWRL, mydat & 0x00ff);
enc28j60Write(MIWRH, mydat >> 8);
// wait until the PHY write completes
while(enc28j60Read(MISTAT) & MISTAT_BUSY)
{
delay_100ns();
}
}
void enc28j60ReadBuffer(u16_t len, u8_t* dat)
{
// assert CS
CSN = 0;
// issue read command
delay_100ns();
WriteByte(ENC28J60_READ_BUF_MEM);
while(len--)
{
*dat++ = ReadByte();
}
// release CS
CSN = 1;
}
void enc28j60WriteBuffer(u16_t len, u8_t* dat)
{
// assert CS
CSN = 0;
// issue write command
WriteByte(ENC28J60_WRITE_BUF_MEM);
// while(!(SPSR & (1<<SPIF)));
while(len--)
{
WriteByte(*dat++);
}
// release CS
CSN = 1;
}
#define ETHERNET_MIN_PACKET_LENGTH 0x3C
#define ETHERNET_HEADER_LENGTH 0x0E
#define IP_TCP_HEADER_LENGTH 40
#define TOTAL_HEADER_LENGTH (IP_TCP_HEADER_LENGTH+ETHERNET_HEADER_LENGTH)
void enc28j60PacketSend(u16_t len, u8_t* packet)
{
// Set the write pointer to start of transmit buffer area
enc28j60Write(EWRPTL, TXSTART_INIT);
enc28j60Write(EWRPTH, TXSTART_INIT>>8);
// Set the TXND pointer to correspond to the packet size given
enc28j60Write(ETXNDL, (TXSTART_INIT+len));
enc28j60Write(ETXNDH, (TXSTART_INIT+len)>>8);
// write per-packet control byte
enc28j60WriteOp(ENC28J60_WRITE_BUF_MEM, 0, 0x00);
// TODO, fix this up
if( uip_len <= TOTAL_HEADER_LENGTH )
{
// copy the packet into the transmit buffer
enc28j60WriteBuffer(len, packet);
}
else
{
len -= TOTAL_HEADER_LENGTH;
enc28j60WriteBuffer(TOTAL_HEADER_LENGTH, packet);
enc28j60WriteBuffer(len, (unsigned char *)uip_appdata);
}
// send the contents of the transmit buffer onto the network
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, ECON1_TXRTS);
}
u16_t enc28j60PacketReceive(u16_t maxlen, u8_t* packet)
{
u16_t rxstat,len;
if (enc28j60Read(EPKTCNT) == 0)
{
return 0;
}
// Set the read pointer to the start of the received packet
enc28j60Write(ERDPTL, (NextPacketPtr));
enc28j60Write(ERDPTH, (NextPacketPtr)>>8);
// read the next packet pointer
NextPacketPtr = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
NextPacketPtr |= (enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0)<<8);
// read the packet length
len = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
len |= (enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0)<<8);
len -= 4; //以太帧最小46字节 减去4字节的FCS校验和 加上帧头14字节 共64字节
//PrintHex(len);
// read the receive status
rxstat = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
rxstat |= enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0)<<8;
// limit retrieve length
// (we reduce the MAC-reported length by 4 to remove the CRC)
len = MIN(len, maxlen);
// copy the packet from the receive buffer
enc28j60ReadBuffer(len, packet);
// Errata workaround #13. Make sure ERXRDPT is odd
u16_t rs,re;
rs = enc28j60Read(ERXSTH);
rs <<= 8;
rs |= enc28j60Read(ERXSTL);
re = enc28j60Read(ERXNDH);
re <<= 8;
re |= enc28j60Read(ERXNDL);
if (NextPacketPtr - 1 < rs || NextPacketPtr - 1 > re)
{
enc28j60Write(ERXRDPTL, (re));
enc28j60Write(ERXRDPTH, (re)>>8);
}
else
{
enc28j60Write(ERXRDPTL, (NextPacketPtr-1));
enc28j60Write(ERXRDPTH, (NextPacketPtr-1)>>8);
}
// decrement the packet counter indicate we are done with this packet
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON2, ECON2_PKTDEC);
return len;
}
void dev_init(void)
{
enc28j60_init();
}
void dev_send(void)
{
enc28j60PacketSend(uip_len, uip_buf);
}
u16_t dev_poll(void)
{
return enc28j60PacketReceive(UIP_BUFSIZE, uip_buf);
}
void enc28j60_init(void)
{
//SPI INIT
SpiInit();
// perform system reset
enc28j60WriteOp(ENC28J60_SOFT_RESET, 0, ENC28J60_SOFT_RESET);
// check CLKRDY bit to see if reset is complete
//while(!(enc28j60Read(ESTAT) & ESTAT_CLKRDY));
// Errata workaround #2, CLKRDY check is unreliable, delay 1 mS instead
delay_ms(5);
// lamp test
// enc28j60PhyWrite(PHLCON, 0x0AA2);
// do bank 0 stuff
// initialize receive buffer
// 16-bit transfers, must write low byte first
// set receive buffer start address
NextPacketPtr = RXSTART_INIT;
enc28j60Write(ERXSTL, RXSTART_INIT&0xFF);
enc28j60Write(ERXSTH, RXSTART_INIT>>8);
// set receive pointer address
enc28j60Write(ERXRDPTL, RXSTART_INIT&0xFF);
enc28j60Write(ERXRDPTH, RXSTART_INIT>>8);
// set receive buffer end
// ERXND defaults to 0x1FFF (end of ram)
enc28j60Write(ERXNDL, RXSTOP_INIT&0xFF);
enc28j60Write(ERXNDH, RXSTOP_INIT>>8);
// set transmit buffer start
// ETXST defaults to 0x0000 (beginnging of ram)
enc28j60Write(ETXSTL, TXSTART_INIT&0xFF);
enc28j60Write(ETXSTH, TXSTART_INIT>>8);
// do bank 2 stuff
// enable MAC receive
enc28j60Write(MACON1, MACON1_MARXEN|MACON1_TXPAUS|MACON1_RXPAUS);
// bring MAC out of reset
enc28j60Write(MACON2, 0x00);
// enable automatic padding and CRC operations
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, MACON3, MACON3_PADCFG0|MACON3_TXCRCEN|MACON3_FRMLNEN);
// enc28j60Write(MACON3, MACON3_PADCFG0|MACON3_TXCRCEN|MACON3_FRMLNEN);
// set inter-frame gap (non-back-to-back)
enc28j60Write(MAIPGL, 0x12);
enc28j60Write(MAIPGH, 0x0C);
// set inter-frame gap (back-to-back)
enc28j60Write(MABBIPG, 0x12);
// Set the maximum packet size which the controller will accept
enc28j60Write(MAMXFLL, MAX_FRAMELEN&0xFF);
enc28j60Write(MAMXFLH, MAX_FRAMELEN>>8);
// do bank 3 stuff
// write MAC address
// NOTE: MAC address in ENC28J60 is byte-backward
enc28j60Write(MAADR5, UIP_ETHADDR0);
enc28j60Write(MAADR4, UIP_ETHADDR1);
enc28j60Write(MAADR3, UIP_ETHADDR2);
enc28j60Write(MAADR2, UIP_ETHADDR3);
enc28j60Write(MAADR1, UIP_ETHADDR4);
enc28j60Write(MAADR0, UIP_ETHADDR5);
// no loopback of transmitted frames
enc28j60PhyWrite(PHCON2, PHCON2_HDLDIS);
// switch to bank 0
enc28j60SetBank(ECON1);
// enable interrutps
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, EIE, EIE_INTIE|EIE_PKTIE);
// enable packet reception
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, ECON1_RXEN);
}
在上面文件中有一个delay_100ns函数,为什么要写这个函数呢,看了enc28j60的输入输出的时序之后发现在cs置低之后只要要保持100ns,所以每次在写入之前都要延迟100ns左右。cc2530的时钟是32MHz,所以差不多3个机器周期就是100ns了。这个是要注意的地方,我在这之前,调试了半天,一直都没发现有网络数据包出来,然后再仔细读了datasheet才发现的。
这个驱动根据datasheet写,或者参考网上的,哈哈,只要能实现就行了。
有了以上驱动程序就很好移植了! 废话不多说,直接给移植步骤。
在网上下载源码,我用的是uip0.9版本。编译环境是IAR,因为cc2530用的是IAR开发环境。
将spi.c enc28j60.c即相关头文件放在driver目录下,将uip.c uip_arp.c uip_arch.c还有相关头文件放在uip目录下,
linker目录下放的是IAR8051的连接文件(可以不用),将应用程序main.c app.c app.h文件放在user目录下。
将uip源代码中unix文件夹中的main函数改一下,其中tapdev_read函数替换成我们的dev_poll,将tapdev_send替换成dev_send,然后将http相关的东西删去,我们先实现简单的功能。
根据源码文件夹中的doc文档,写个简单的历程。
app.c的代码如下:
#include "app.h"
#include "uip.h"
void example1_init(void)
{
uip_listen(HTONS(1234));
}
void example1_appcall(void)
{
struct example1_state *s;
s = (struct example1_state *)uip_conn->appstate;
if(uip_connected()) {
s->state = WELCOME_SENT;
uip_send("Welcome!\n", 9);
return;
}
if(uip_acked() && s->state == WELCOME_SENT) {
s->state = WELCOME_ACKED;
}
if(uip_newdata()) {
uip_send("ok\n", 3);
}
if(uip_rexmit()) {
switch(s->state) {
case WELCOME_SENT:
uip_send("Welcome!\n", 9);
break;
case WELCOME_ACKED:
uip_send("ok\n", 3);
break;
}
}
}
对了,还有个重要的问题,就是大小端的问题,这个也是我调试好久未果的一个经验。cc2530是8051内核的,是小端,所以在uipopt.h文件中做如下改动
#ifndef BYTE_ORDER
#define BYTE_ORDER LITTLE_ENDIAN
#endif /* BYTE_ORDER */
还有个编译设置的问题,具体按照如下来:
好了,然后编译连接,过程中可能有一些警告和错误,一个一个耐心排除,很容易。
用网线连上电脑,然后打开命令终端,输入ping 219.223.173.242 我主机ip是219.223.173.243
如下结果:
然后打开网络调试助手
如程序需要的结果相同,哈哈!过几天实现一个web服务器!