view ostc4pack/src/checksum_final_add_fletcher.cpp @ 325:8e62f4701676 fix-batt-1

bugfix: implement battery at end in dive header For some reason, the byte 50/51 data in the dive header was not populated at the end of dive. These bytes represent the battery voltage (in mV) at end in dive. Simply implement it in this commit. Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>
author Jan Mulder <jlmulder@xs4all.nl>
date Thu, 20 Jun 2019 14:24:57 +0200
parents 1e707b34667e
children 01f40cb1057e
line wrap: on
line source

#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>

void fletcher16(unsigned char *result1, unsigned char *result2, unsigned char const *data, size_t bytes )
{
        unsigned short sum1 = 0xff, sum2 = 0xff;
        size_t tlen;
 
        while (bytes) {
                tlen = bytes >= 20 ? 20 : bytes;
                bytes -= tlen;
                do {
                        sum2 += sum1 += *data++;
                } while (--tlen);
                sum1 = (sum1 & 0xff) + (sum1 >> 8);
                sum2 = (sum2 & 0xff) + (sum2 >> 8);
        }
        /* Second reduction step to reduce sums to 8 bits */
        sum1 = (sum1 & 0xff) + (sum1 >> 8);
        sum2 = (sum2 & 0xff) + (sum2 >> 8);
        *result2 = (sum2 & 0xff);
        *result1 = (sum1 & 0xff);
//        return sum2 << 8 | sum1;
}


// This is a variant of fletcher16 with a 16 bit sum instead of an 8 bit sum,
// and modulo 2^16 instead of 2^16-1
void
hw_ostc3_firmware_checksum (unsigned char *result1, unsigned char *result2, unsigned char *result3, unsigned char *result4, unsigned char const *data, size_t bytes )
{
	unsigned short low = 0;
	unsigned short high = 0;
	for (unsigned int i = 0; i < bytes; i++) {
		low  += data[i];
		high += low;
	}
        *result1 = (low & 0xff);
        *result2 = (low/256 & 0xff);
        *result3 = (unsigned char)(high & 0xff);
        *result4 = (unsigned char)((high/256) & 0xff);
//	return (((unsigned int)high) << 16) + low;
}


int main(int argc, char** argv) {
	
	
	FILE *fp, * fpout;
	size_t lenTotal,lenTemp;
	unsigned char buf[2000000];
	char *file = argv[1];
	char *file2 =  argv[2];
	char *file3 =  argv[3];
	unsigned int pruefsumme;
	unsigned char buf2[4];

   	printf("1: %s\n",  file);
   	printf("2: %s\n",  file2);
   	printf("3: %s\n",  file3);
   	printf("\n");
     
	
		//write File with length and cheksum
	char filename[500], filenameout[510] ;
	sprintf(filename,"%s",file);
	int filelength = strlen(filename);
	filename[filelength -4] = 0;
	
	lenTotal = 0;
	if (NULL == (fp = fopen(file, "rb")))
	{
	    printf("Unable to open %s for reading\n", file);
	    return -1;
	}
	lenTemp = fread(&buf[lenTotal], sizeof(char), sizeof(buf), fp);
//	lenTemp = fread(buf, sizeof(char), sizeof(buf), fp);
	lenTotal = lenTemp;
	printf("%d bytes read (hex: %#x )\n", lenTemp,lenTemp);
	fclose(fp);

	if(file2)
	{
		if (NULL == (fp = fopen(file2, "rb")))
		{
		    printf("Unable to open %s for reading\n", file2);
		    return -1;
		}
		lenTemp = fread(&buf[lenTotal], sizeof(char), sizeof(buf)-lenTotal, fp);
		lenTotal += lenTemp;
		printf("%d bytes read (hex: %#x )\n", lenTemp,lenTemp);
		fclose(fp);
	}
	if(file3)
	{
		if (NULL == (fp = fopen(file3, "rb")))
		{
		    printf("Unable to open %s for reading\n", file3);
		    return -1;
		}
		lenTemp = fread(&buf[lenTotal], sizeof(char), sizeof(buf)-lenTotal, fp);
		lenTotal += lenTemp;
		printf("%d bytes read (hex: %#x )\n", lenTemp,lenTemp);
		fclose(fp);
	}

   	printf("\n");
	printf("%d bytes read (hex: %#x ) total \n", lenTotal,lenTotal);

	time_t rawtime;
	time (&rawtime);
	struct tm *timeinfo;
	timeinfo = localtime(&rawtime);
	
//	sprintf(filenameout,"fwupdate_%s.bin",ctime(&rawtime));
	sprintf(filenameout,"OSTC4update_%02u%02u%02u.bin",timeinfo->tm_year-100,timeinfo->tm_mon+1,timeinfo->tm_mday);

    fpout = fopen(filenameout, "wb");     
    for(int i = 0;i <lenTotal;i++)
    {
    	if(fwrite(&buf[i],1,1,fpout) != 1)
     	printf("error writing\n");
	}
	
	hw_ostc3_firmware_checksum(&buf2[0],&buf2[1],&buf2[2],&buf2[3],buf,lenTotal);
	printf("checksum  %#x %#x %#x %#x\n", buf2[0],buf2[1], buf2[2], buf2[3]);
   	if(fwrite(&buf2[0],1,4,fpout) != 4)
    	printf("error writing checksum\n");
    ;
	fclose(fpout);
}