Hexadecimal to string

// Two 16 Hexadecimal characters are converted to one byte

int IsLowercase(signed int character)
{
  int result;
  result = character >= 'a' && character < '{';
  return result;
}

int  UpperCaseToLower(int Character)
{
  if ( IsLowercase(Character) )
    Character -= 32;
  return Character;
}

// Here is the fixed input of even characters 16 Hexadecimal characters
void  StrToHex(uint8_t *HexStr, uint8_t *HexNum,int hexCount)
{
  uint8_t *tHexStr; // r7
  uint8_t *tHexNum; // r4
  signed int Count; // r6
  int HexResult; // r8
  char LowCaseCharacter; // r0
  char tCount; // r0
  int i = hexCount;

  tHexStr = HexStr;
  tHexNum = HexNum;
  Count = 0;
  HexResult = 0;
  while ( Count < i && *tHexStr )
  {
    LowCaseCharacter = UpperCaseToLower((char)*tHexStr++);
    // Judge non numbers
    if ( LowCaseCharacter < 0x30 || LowCaseCharacter >= 0x3A ) {
        if ( LowCaseCharacter < 'A' || LowCaseCharacter >= 'G' )// If not A-F Between the character values Then exit by mistake
        {
        //printf((int)"key must be in hexadecimal notation\n");
        return;
        }
      HexResult = LowCaseCharacter + 16 * HexResult - 0x37;// If it is A-F The number in
    }else {
      HexResult = LowCaseCharacter + 16 * HexResult - 0x30;// If it's a number
    }
    tCount = Count++;
    if ( tCount & 1 )  // If the current reading is an odd number Then it is not stored in the array If it's an even number Just put the two together in the array
      tHexNum[Count / 2 - 1] = HexResult;
  }
}

void HexToAscii(uint8_t *pHex, uint8_t *pAscii, int nLen)
{
    unsigned char Nibble[2];
    unsigned int i,j;
    for (i = 0; i < nLen; i++){
        Nibble[0] = (pHex[i] & 0xF0) >> 4;
        Nibble[1] = pHex[i] & 0x0F;
        for (j = 0; j < 2; j++){
            if (Nibble[j] < 10){
                Nibble[j] += 0x30;
            }
            else{
                if (Nibble[j] < 16)
                    Nibble[j] = Nibble[j] - 10 + 'A';
            }
            *pAscii++ = Nibble[j];
        }
    }
}