起因

Modelsim中的结果是以十六进制有符号数的形式给出的，不方便观察，所以想把它转成十进制数，然而没有找到合适的工具，无奈自己用C语言写了一个。

运行结果

Code

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

char* fun(char ch);

char str1[] = "1234";

int main()
{
	int width = 16;
	char hex[] = "ffffffff";
	char *complement;
	char *t_complement;
	char *reverse;
	char *original;
	int B_num = 0;
	int data = 0;
	int scanf_len = 0;

	int i;

	while(1){

		printf("\n请输入宽度:");
		scanf("%d", &width);
		printf("\n请输入十六进制数:");
		scanf_len = scanf("%s", hex);

		B_num = (width+3)/4;

		if( strlen(hex)!= B_num)
		{
			printf("！！！输入错误！！！");
			exit(0);
		}
		else
		{
			printf("十六进制数：%s\n", hex);
		}

		complement = (char*)malloc((B_num*4+5)*sizeof(char));
		memset(complement, 0, sizeof(complement));

		t_complement = (char*)malloc((width+5)*sizeof(char));
		memset(t_complement, 0, sizeof(t_complement));

		reverse = (char*)malloc((width+5)*sizeof(char));
		memset(reverse, 0, sizeof(reverse));

		original = (char*)malloc((width+5)*sizeof(char));
		memset(original, 0, sizeof(original));

		for(i=0; i<B_num; i++)
		{
			// ????????¡ã¨¦????????????????????¨¦????¡ã????????????
			memcpy(complement+4*i, fun(hex[i]), 4);
		}
		complement[B_num*4] = '\0';

		for(i=0; i<width; i++)
		{
			t_complement[i] = complement[i+(B_num*4-width)];
		}
		t_complement[width] = 0;

		if(t_complement[0] == '1')
		{

			// 	?¡¦????complement???¨¦??????????????
			for(i=0+(B_num*4-width); i<B_num*4; i++)
			{
				if(i == (B_num*4-width))
					reverse[i-(B_num*4-width)] = complement[i];
				else if(complement[i] == '1')
					reverse[i-(B_num*4-width)] = '0';
				else
					reverse[i-(B_num*4-width)] = '1';
			}
			reverse[width] = 0;

			char carry = 1;
			// 	?¡¦????complement???¨¦??????????????
			for(i=width-1; i>=0; i--)
			{
				if(i == 0)
					original[i] = reverse[i];
				else if(carry == 1){
					if(reverse[i] == '1'){
						original[i] = '0';
						carry = 1;
					}
					else{
						original[i] = '1';
						carry = 0;
					}
				}
				else{
					if(reverse[i] == '1'){
						original[i] = '1';
					}
					else{
						original[i] = '0';
					}
				}
			}
			original[width] = 0;
		}
		else{
			memcpy(reverse, t_complement, width);
			memcpy(original, t_complement, width);
		}

		int base = 1;
		for(i=width-1; i>=0; i--)
		{
			if(i == 0){
				if(original[i] == '1')
					data *= -1;
			}
			else{
				data = data + (original[i]-'0')*base;
				base *= 2;
			}
		}


		// printf("%d %d %d", sizeof(int), sizeof(long int), sizeof(long long int));

		printf("原码:%s\n", complement);
		printf("原码:%s\n", t_complement);
		printf("反码:%s\n", reverse);
		printf("补码:%s\n", original);
		printf("十进制数：%d\n", data);

		printf("=================================================\n\n");
	}

	return 0;
}


char* fun(char ch)
{
	switch(ch)
	{
		case '0':
			memcpy(str1, "0000", 4);
			break;
		case '1':
			memcpy(str1, "0001", 4);
			break;
		case '2':
			memcpy(str1, "0010", 4);
			break;
		case '3':
			memcpy(str1, "0011", 4);
			break;
		case '4':
			memcpy(str1, "0100", 4);
			break;
		case '5':
			memcpy(str1, "0101", 4);
			break;
		case '6':
			memcpy(str1, "0110", 4);
			break;
		case '7':
			memcpy(str1, "0111", 4);
			break;
		case '8':
			memcpy(str1, "1000", 4);
			break;
		case '9':
			memcpy(str1, "1001", 4);
			break;
		case 'a':
		case 'A':
			memcpy(str1, "1010", 4);
			break;
		case 'b':
		case 'B':
			memcpy(str1, "1011", 4);
			break;
		case 'c':
		case 'C':
			memcpy(str1, "1100", 4);
			break;
		case 'd':
		case 'D':
			memcpy(str1, "1101", 4);
			break;
		case 'e':
		case 'E':
			memcpy(str1, "1110", 4);
			break;
		case 'f':
		case 'F':
			memcpy(str1, "1111", 4);
			break;
		default:
			printf("???????????¨ª?¨®??????\n");
			exit(0);
			break;
	}
	return str1;
}