source: buchla-68k/orig/GEMDOS/MSREC.C

/*
   ============================================================================
        msrec.c -- Motorola S-record output functions
        Version 6 -- 1987-07-10 -- D.N. Lynx Crowe
        (c) Copyright 1987 -- D.N. Lynx Crowe

        This file contains functions which will output a buffer as a group
        of Motorola S-records.  These functions will output type 2
        S-records for the data  (3 byte addresses).  Output is to a
        specified file, which must be open when the function is called, and
        which will be left open by the function.  The last record will be
        a type 9 S-record.

        void                    Output a buffer as S-records
        msrec(fp, adr, len, buf)
        FILE *fp;               file pointer for output
        long adr;               beginning address for S-records
        long len;               length of data in buffer
        char *buf;              buffer address

        void                    Output a single S-record
        outrec(fp, adr, len, buf)
        FILE *fp;               file pointer for output
        long adr;               beginning address for S-record
        int len;                length of data in record
        char *buf;              buffer address of record

        void                    Output a byte as 2 ASCII hex characters
        outhex(fp, val)
        FILE *fp;               file pointer for output
        unsigned int val;       byte to be output
   ============================================================================
*/

#define TESTER  0               /* define non-zero to get a test program */

#define VOID

#include "stdio.h"

static int csum;                                /* checsum for current record */
static char hexdig[] = "0123456789ABCDEF";      /* hex table */

#define RECLEN  32              /* 32 bytes per S-record */

#define GE      >=

/* 
 */

/*
   ============================================================================
        outhex(fp, val) -- output a byte in ASCII hex

        Outputs the byte val on file fp in ASCII hex and updates
        the accumulated checksum csum.
   ============================================================================
*/

VOID
outhex(fp, val)
FILE *fp;               /* file pointer for output */
unsigned int val;       /* byte to be output */
{
        fputc(hexdig[(val >> 4) & 0x0F], fp);
        fputc(hexdig[val & 0x0F], fp);
        csum += (val & 0x0FF);
}

/* 

*/

/*
   ============================================================================
        outrec(fp, adr, len, buf) -- output a Motorola S-record

        Outputs len bytes from buffer buf to file fp with S-record
        address adr.
   ============================================================================
*/

VOID
outrec(fp, adr, len, buf)
FILE *fp;               /* file pointer for output */
long adr;               /* beginning address for S-record */
register int len;       /* length of data in record */
register char *buf;     /* buffer address of record */
{
        register int i;

        csum = 0;                               /* zero the checksum */
        fprintf(fp, "S2");                      /* record header */
        outhex(fp, (unsigned int)(len+4));      /* record length */

        /* record address */

        outhex(fp, (unsigned int)((adr >> 16) & 0x0FFL));
        outhex(fp, (unsigned int)((adr >> 8) & 0x0FFL));
        outhex(fp, (unsigned int)(adr & 0x0FFL));

        /* data */

        for (i = 0; i < len; i++)
                outhex(fp, (unsigned int)*buf++);

        outhex(fp, (~csum) & 0x0FFL);           /* checksum */
        fprintf(fp, "\n");                      /* CR/LF */
}

/* 
 */

/*
   ============================================================================
        msrec(fp, adr, len, buf) -- output data in Motorola S-record format

        Outputs 'len' bytes of data from buffer 'buf' to file pointer 'fp'
        with an initial S-record address of 'adr'.
   ============================================================================
*/

VOID
msrec(fp, recadr, len, rp)
FILE *fp;               /* file pointer for output */
register long recadr;   /* beginning address for S-records */
register long len;      /* length of data in buffer */
register char *rp;      /* buffer address */
{
        register int ilen;

        while (len) {   /* while there's data ... */

                if (len GE RECLEN) {    /* full record */

                        outrec(fp, recadr, RECLEN, rp);
                        len -= RECLEN;
                        rp += RECLEN;
                        recadr += RECLEN;

                } else {                /* final short record */

                        ilen = len;
                        outrec(fp, recadr, ilen ,rp);
                        len = 0;

                }
        }

        fprintf(fp, "S904000000FB\n");  /* end of S-records */
}

/* 
 */

#if     TESTER

/*
   ============================================================================
        test routine for msrec
   ============================================================================
*/

main()
{
        printf("Test of msrec\nShort record of 16 bytes\n\n");
        msrec(stdout, 0L, 16L, &hexdig);

        printf("\nRecord of 256 bytes\n\n");
        msrec(stdout, 0x0FC0000L, 256L, (char *)0x0FC0000L);

        printf("\nRecord of 45 bytes\n\n");
        msrec(stdout, 0x0FC0000L,  45L, (char *)0x0FC0000L);

        printf("\nEnd of test\n");
        fclose(stdout);

        exit(0);
}

#endif