c语言float转bcd码

//基于查表实现BCD与Ascii之间的转换
static uint8_t bcd2ascii[16] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

static uint8_t ascii2bcd1[10] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
static uint8_t ascii2bcd2[6] = { 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F };



uint32_t
ASC2BCD(uint8_t* bcd, const uint8_t* asc, uint32_t len)
{
    uint8_t c = 0;
    uint8_t index = 0;
    uint8_t i = 0;

    len >>= 1;

    for (; i < len; i++) {
        //first BCD
        if (*asc >= 'A' && *asc <= 'F') {
            index = *asc - 'A';
            c = ascii2bcd2[index] << 4;
        }
        else if (*asc >= '0' && *asc <= '9') {
            index = *asc - '0';
            c = ascii2bcd1[index] << 4;
        }
        asc++;

        //second BCD
        if (*asc >= 'A' && *asc <= 'F') {
            index = *asc - 'A';
            c |= ascii2bcd2[index];
        }
        else if (*asc >= '0' && *asc <= '9') {
            index = *asc - '0';
            c |= ascii2bcd1[index];
        }
        asc++;

        *bcd++ = c;
    }

    return 0;
}


uint32_t
BCD2ASC(uint8_t* asc, const uint8_t* bcd, uint32_t len)
{
    uint8_t c = 0;
    uint8_t i;


    for (i = 0; i < len; i++) {
        //first BCD
        c = *bcd >> 4;
        *asc++ = bcd2ascii[c];


        //second
        c = *bcd & 0x0f;
        *asc++ = bcd2ascii[c];
        bcd++;
    }


    return 0;
}



int float_to_asc(float num, char *asc)
{
    if (!asc)
        return -1;
    sprintf((char *)asc,"%.2f",num);
    return 1;
}

使用：

float num = 21.33;
   char asc[12] = { 0 };
  float_to_asc(num,asc);
  uint8_t bcd[6] = { 0 };
  uint8_t temp[12] = { 0 };
  memcpy(temp+12-strlen(asc),asc, strlen(asc));
//  memset(bcd,'0',6);
  ASC2BCD(bcd, (uint8_t *)temp,12);
  display_hex(bcd, 6,1);