hex2ten.c

huge hex convert to dec. the value limite is less that 10^50

#include "string.h"
#include "stdio.h"

unsigned char g_BCD_array[40];

void HEX2DEC(unsigned char *hex_value,unsigned char *value_H)
{
	unsigned char value;
	value = *hex_value / 10;
	*value_H = value;
	*hex_value = *hex_value - value*10;
}

void DEC_MUL(unsigned char *BCD_array,unsigned char n,int array_count) //n<10
{
	int i;
	unsigned char temp_L=0,temp_H=0;
	for(i=0;i<array_count;i++)
	{
		temp_L = BCD_array[i] * n;
		temp_L += temp_H;
		HEX2DEC(&temp_L,&temp_H);
		BCD_array[i] = temp_L;
	}
}
void DEC_MUL_ten(unsigned char *BCD_array,int array_count)
{
	int i;
	for(i = array_count-1;i>0;i--)
	{	
		BCD_array[i] = BCD_array[i-1];
	}
	BCD_array[i] = 0;
}
void DEC_ADD(unsigned char *BCD_array1,unsigned char *BCD_array2,int array_count1,int array_count2)
{
	int i;
	unsigned char temp_L=0,temp_H=0;
	for(i=0;i<array_count1;i++)
	{
		if(i>=array_count2)
			temp_L = BCD_array1[i];
		else
			temp_L = BCD_array1[i] + BCD_array2[i];
		temp_L += temp_H;
		HEX2DEC(&temp_L,&temp_H);
		BCD_array1[i] = temp_L;
	}
}
void DEC_MUL_16(unsigned char *T_BCD_array,int array_count)
{
	unsigned char BCD_array[40];
	memcpy(BCD_array,T_BCD_array,array_count);
	DEC_MUL_ten(T_BCD_array,array_count);
	DEC_MUL(BCD_array,6,array_count);
	DEC_ADD(T_BCD_array,BCD_array,array_count,array_count);
}

void hex2ten(unsigned short *T_value,int length)
{
	unsigned short value[20];
	unsigned char numBCD[3]={0,0,0};
	unsigned char temp_L=0,temp_H=0;
	int i;

	memset(g_BCD_array,0,40);
	memset(value,0x0000,40);

	memcpy(value,T_value,length);

	for(i = 19;i>=0;i--)
	{
		DEC_MUL_16(g_BCD_array,40);

		temp_L = (unsigned char)(value[i] >>12);
		temp_L &= 0x0f;
		HEX2DEC(&temp_L,&temp_H);
		numBCD[0] = temp_L;
		numBCD[1] = temp_H;
		DEC_ADD(g_BCD_array,numBCD,40,3);
		DEC_MUL_16(g_BCD_array,40);

		temp_L = (unsigned char)(value[i] >>8);
		temp_L &= 0x0f;
		HEX2DEC(&temp_L,&temp_H);
		numBCD[0] = temp_L;
		numBCD[1] = temp_H;
		DEC_ADD(g_BCD_array,numBCD,40,3);
		DEC_MUL_16(g_BCD_array,40);

		temp_L = (unsigned char)((value[i] >>4)&0x000f);
		temp_L &= 0x0f;
		HEX2DEC(&temp_L,&temp_H);
		numBCD[0] = temp_L;
		numBCD[1] = temp_H;
		DEC_ADD(g_BCD_array,numBCD,40,3);
		DEC_MUL_16(g_BCD_array,40);
		
		temp_L = (unsigned char)(value[i] &0x000f);
		temp_L &= 0x0f;
		HEX2DEC(&temp_L,&temp_H);
		numBCD[0] = temp_L;
		numBCD[1] = temp_H;
		DEC_ADD(g_BCD_array,numBCD,40,3);
	
	}
	printf("\n\r");
	for(i = 39;i>=0;i--)
	{
		printf("%d ",g_BCD_array[i]);
	}
	printf("\n\r");
}
main()
{
    unsigned short value[8]={1,2,3,4,0,0,0,0};
	hex2ten(value,8);

	



}