文件传输(xmodem协议)

https://www.menie.org/georges/embedded/

需要移植如下两个基础读写函数

int _inbyte(unsigned short timeout);

void _outbyte(int c);

xmodem.c

/*
 * Copyright 2001-2010 Georges Menie (www.menie.org)
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the University of California, Berkeley nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/* this code needs standard functions memcpy() and memset()
   and input/output functions _inbyte() and _outbyte().

   the prototypes of the input/output functions are:
     int _inbyte(unsigned short timeout); // msec timeout
     void _outbyte(int c);

 */

#include "crc16.h"

#define SOH  0x01
#define STX  0x02
#define EOT  0x04
#define ACK  0x06
#define NAK  0x15
#define CAN  0x18
#define CTRLZ 0x1A

#define DLY_1S 1000
#define MAXRETRANS 25

void _outbyte(int c)
{
        while ((readb(UTX1) & 0x20) == )
                ;

        writeb ((char)c,UTX1+);
}

void outbyte(int c)
{
        static char prev = ;
        if (c < ' ' && c != '\r' && c != '\n' && c != '\t' && c != '\b')
                return;
        if (c == '\n' && prev != '\r') _outbyte('\r');
        _outbyte(c);
        prev = c;
}

int _inbyte(unsigned short timeout) // msec timeout
{
        unsigned short c;
        int delay = timeout << ;

        while (((c=readw(URX1)) & 0x2000) == ) {
                usleep(); /* 60 us * 16 = 960 us (~ 1 ms) */
                if (timeout) {
                        if (--delay == ) return -;
                }
        }

        return c & 0x0FF;
}

unsigned short crc16_ccitt( const void *buf, int len )
{
    unsigned short crc = ;
    while( len-- ) {
        int i;
        crc ^= *(char *)buf++ << ;
        for( i = ; i < ; ++i ) {
            if( crc & 0x8000 )
                crc = (crc << ) ^ 0x1021;
            else
                crc = crc << ;
        }
    }
    return crc;
}

static int check(int crc, const unsigned char *buf, int sz)
{
    if (crc) {
        unsigned short crc = crc16_ccitt(buf, sz);
        unsigned short tcrc = (buf[sz]<<)+buf[sz+];
        if (crc == tcrc)
            return ;
    }
    else {
        int i;
        unsigned char cks = ;
        for (i = ; i < sz; ++i) {
            cks += buf[i];
        }
        if (cks == buf[sz])
        return ;
    }

    return ;
}

static void flushinput(void)
{
    while (_inbyte(((DLY_1S)*)>>) >= )
        ;
}

int xmodemReceive(unsigned char *dest, int destsz)
{
    unsigned char xbuff[]; /* 1024 for XModem 1k + 3 head chars + 2 crc + nul */
    unsigned char *p;
    int bufsz, crc = ;
    unsigned char trychar = 'C';
    unsigned char packetno = ;
    int i, c, len = ;
    int retry, retrans = MAXRETRANS;

    for(;;) {
        for( retry = ; retry < ; ++retry) {
            if (trychar) _outbyte(trychar);
            if ((c = _inbyte((DLY_1S)<<)) >= ) {
                switch (c) {
                case SOH:
                    bufsz = ;
                    goto start_recv;
                case STX:
                    bufsz = ;
                    goto start_recv;
                case EOT:
                    flushinput();
                    _outbyte(ACK);
                    return len; /* normal end */
                case CAN:
                    if ((c = _inbyte(DLY_1S)) == CAN) {
                        flushinput();
                        _outbyte(ACK);
                        return -; /* canceled by remote */
                    }
                    break;
                default:
                    break;
                }
            }
        }
        if (trychar == 'C') { trychar = NAK; continue; }
        flushinput();
        _outbyte(CAN);
        _outbyte(CAN);
        _outbyte(CAN);
        return -; /* sync error */

    start_recv:
        if (trychar == 'C') crc = ;
        trychar = ;
        p = xbuff;
        *p++ = c;
        for (i = ;  i < (bufsz+(crc?:)+); ++i) {
            if ((c = _inbyte(DLY_1S)) < ) goto reject;
            *p++ = c;
        }

        if (xbuff[] == (unsigned char)(~xbuff[]) &&
            (xbuff[] == packetno || xbuff[] == (unsigned char)packetno-) &&
            check(crc, &xbuff[], bufsz)) {
            if (xbuff[] == packetno)    {
                register int count = destsz - len;
                if (count > bufsz) count = bufsz;
                if (count > ) {
                    memcpy (&dest[len], &xbuff[], count);
                    len += count;
                }
                ++packetno;
                retrans = MAXRETRANS+;
            }
            if (--retrans <= ) {
                flushinput();
                _outbyte(CAN);
                _outbyte(CAN);
                _outbyte(CAN);
                return -; /* too many retry error */
            }
            _outbyte(ACK);
            continue;
        }
    reject:
        flushinput();
        _outbyte(NAK);
    }
}

int xmodemTransmit(unsigned char *src, int srcsz)
{
    unsigned char xbuff[]; /* 1024 for XModem 1k + 3 head chars + 2 crc + nul */
    int bufsz, crc = -;
    unsigned char packetno = ;
    int i, c, len = ;
    int retry;

    for(;;) {
        for( retry = ; retry < ; ++retry) {
            if ((c = _inbyte((DLY_1S)<<)) >= ) {
                switch (c) {
                case 'C':
                    crc = ;
                    goto start_trans;
                case NAK:
                    crc = ;
                    goto start_trans;
                case CAN:
                    if ((c = _inbyte(DLY_1S)) == CAN) {
                        _outbyte(ACK);
                        flushinput();
                        return -; /* canceled by remote */
                    }
                    break;
                default:
                    break;
                }
            }
        }
        _outbyte(CAN);
        _outbyte(CAN);
        _outbyte(CAN);
        flushinput();
        return -; /* no sync */

        for(;;) {
        start_trans:
            xbuff[] = SOH; bufsz = ;
            xbuff[] = packetno;
            xbuff[] = ~packetno;
            c = srcsz - len;
            if (c > bufsz) c = bufsz;
            if (c >= ) {
                memset (&xbuff[], , bufsz);
                if (c == ) {
                    xbuff[] = CTRLZ;
                }
                else {
                    memcpy (&xbuff[], &src[len], c);
                    if (c < bufsz) xbuff[+c] = CTRLZ;
                }
                if (crc) {
                    unsigned short ccrc = crc16_ccitt(&xbuff[], bufsz);
                    xbuff[bufsz+] = (ccrc>>) & 0xFF;
                    xbuff[bufsz+] = ccrc & 0xFF;
                }
                else {
                    unsigned char ccks = ;
                    for (i = ; i < bufsz+; ++i) {
                        ccks += xbuff[i];
                    }
                    xbuff[bufsz+] = ccks;
                }
                for (retry = ; retry < MAXRETRANS; ++retry) {
                    for (i = ; i < bufsz++(crc?:); ++i) {
                        _outbyte(xbuff[i]);
                    }
                    if ((c = _inbyte(DLY_1S)) >=  ) {
                        switch (c) {
                        case ACK:
                            ++packetno;
                            len += bufsz;
                            goto start_trans;
                        case CAN:
                            if ((c = _inbyte(DLY_1S)) == CAN) {
                                _outbyte(ACK);
                                flushinput();
                                return -; /* canceled by remote */
                            }
                            break;
                        case NAK:
                        default:
                            break;
                        }
                    }
                }
                _outbyte(CAN);
                _outbyte(CAN);
                _outbyte(CAN);
                flushinput();
                return -; /* xmit error */
            }
            else {
                for (retry = ; retry < ; ++retry) {
                    _outbyte(EOT);
                    if ((c = _inbyte((DLY_1S)<<)) == ACK) break;
                }
                flushinput();
                return (c == ACK)?len:-;
            }
        }
    }
}

#ifdef TEST_XMODEM_RECEIVE
int main(void)
{
    int st;

    printf ("Send data using the xmodem protocol from your terminal emulator now...\n");
    /* the following should be changed for your environment:
       0x30000 is the download address,
       65536 is the maximum size to be written at this address
     */
    st = xmodemReceive((char *)0x30000, );
    if (st < ) {
        printf ("Xmodem receive error: status: %d\n", st);
    }
    else  {
        printf ("Xmodem successfully received %d bytes\n", st);
    }

    return ;
}
#endif
#ifdef TEST_XMODEM_SEND
int main(void)
{
    int st;

    printf ("Prepare your terminal emulator to receive data now...\n");
    /* the following should be changed for your environment:
       0x30000 is the download address,
       12000 is the maximum size to be send from this address
     */
    st = xmodemTransmit((char *)0x30000, );
    if (st < ) {
        printf ("Xmodem transmit error: status: %d\n", st);
    }
    else  {
        printf ("Xmodem successfully transmitted %d bytes\n", st);
    }

    return ;
}
#endif

crc16.c

/*
 * Copyright 2001-2010 Georges Menie (www.menie.org)
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the University of California, Berkeley nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "crc16.h"

/* CRC16 implementation acording to CCITT standards */

static const unsigned short crc16tab[]= {
    0x0000,0x1021,0x2042,0x3063,0x4084,0x50a5,0x60c6,0x70e7,
    0x8108,0x9129,0xa14a,0xb16b,0xc18c,0xd1ad,0xe1ce,0xf1ef,
    0x1231,0x0210,0x3273,0x2252,0x52b5,0x4294,0x72f7,0x62d6,
    0x9339,0x8318,0xb37b,0xa35a,0xd3bd,0xc39c,0xf3ff,0xe3de,
    0x2462,0x3443,0x0420,0x1401,0x64e6,0x74c7,0x44a4,0x5485,
    0xa56a,0xb54b,0x8528,0x9509,0xe5ee,0xf5cf,0xc5ac,0xd58d,
    0x3653,0x2672,0x1611,0x0630,0x76d7,0x66f6,0x5695,0x46b4,
    0xb75b,0xa77a,0x9719,0x8738,0xf7df,0xe7fe,0xd79d,0xc7bc,
    0x48c4,0x58e5,0x6886,0x78a7,0x0840,0x1861,0x2802,0x3823,
    0xc9cc,0xd9ed,0xe98e,0xf9af,0x8948,0x9969,0xa90a,0xb92b,
    0x5af5,0x4ad4,0x7ab7,0x6a96,0x1a71,0x0a50,0x3a33,0x2a12,
    0xdbfd,0xcbdc,0xfbbf,0xeb9e,0x9b79,0x8b58,0xbb3b,0xab1a,
    0x6ca6,0x7c87,0x4ce4,0x5cc5,0x2c22,0x3c03,0x0c60,0x1c41,
    0xedae,0xfd8f,0xcdec,0xddcd,0xad2a,0xbd0b,0x8d68,0x9d49,
    0x7e97,0x6eb6,0x5ed5,0x4ef4,0x3e13,0x2e32,0x1e51,0x0e70,
    0xff9f,0xefbe,0xdfdd,0xcffc,0xbf1b,0xaf3a,0x9f59,0x8f78,
    0x9188,0x81a9,0xb1ca,0xa1eb,0xd10c,0xc12d,0xf14e,0xe16f,
    0x1080,0x00a1,0x30c2,0x20e3,0x5004,0x4025,0x7046,0x6067,
    0x83b9,0x9398,0xa3fb,0xb3da,0xc33d,0xd31c,0xe37f,0xf35e,
    0x02b1,0x1290,0x22f3,0x32d2,0x4235,0x5214,0x6277,0x7256,
    0xb5ea,0xa5cb,0x95a8,0x8589,0xf56e,0xe54f,0xd52c,0xc50d,
    0x34e2,0x24c3,0x14a0,0x0481,0x7466,0x6447,0x5424,0x4405,
    0xa7db,0xb7fa,0x8799,0x97b8,0xe75f,0xf77e,0xc71d,0xd73c,
    0x26d3,0x36f2,0x0691,0x16b0,0x6657,0x7676,0x4615,0x5634,
    0xd94c,0xc96d,0xf90e,0xe92f,0x99c8,0x89e9,0xb98a,0xa9ab,
    0x5844,0x4865,0x7806,0x6827,0x18c0,0x08e1,0x3882,0x28a3,
    0xcb7d,0xdb5c,0xeb3f,0xfb1e,0x8bf9,0x9bd8,0xabbb,0xbb9a,
    0x4a75,0x5a54,0x6a37,0x7a16,0x0af1,0x1ad0,0x2ab3,0x3a92,
    0xfd2e,0xed0f,0xdd6c,0xcd4d,0xbdaa,0xad8b,0x9de8,0x8dc9,
    0x7c26,0x6c07,0x5c64,0x4c45,0x3ca2,0x2c83,0x1ce0,0x0cc1,
    0xef1f,0xff3e,0xcf5d,0xdf7c,0xaf9b,0xbfba,0x8fd9,0x9ff8,
    0x6e17,0x7e36,0x4e55,0x5e74,0x2e93,0x3eb2,0x0ed1,0x1ef0
};

unsigned short crc16_ccitt(const void *buf, int len)
{
    register int counter;
    register unsigned short crc = ;
    for( counter = ; counter < len; counter++)
        crc = (crc<<) ^ crc16tab[((crc>>) ^ *(char *)buf++)&0x00FF];
    return crc;
}

crc16.h

/*
 * Copyright 2001-2010 Georges Menie (www.menie.org)
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the University of California, Berkeley nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _CRC16_H_
#define _CRC16_H_

unsigned short crc16_ccitt(const void *buf, int len);

#endif /* _CRC16_H_ */

附件打包下载

http://files.cnblogs.com/files/dong1/xmodem.c.zip