Int_To_Hex_Digit function

[xezon]

char Int_To_Hex_Digit(int num)
{
    if (num >= 16) {
        return '\0';
    }

    if (num >= 10) {
        return num + '7';
    }

    return num + '0';
}

Can be improved to

char Int_To_Hex_Digit(int num)
{
    if (num >= 16) {
        return '\0';
    }

    if (num >= 10) {
        return num - 10 + 'A';
    }

    return num + '0';
}

or

char Int_To_Hex_Digit(int num)
{
    if (num < 10) {
        return num + '0';
    }
    else if (num < 16) {
        return num - 10 + 'A';
    }
    else {
        return '\0';
    }
}

The latter could run faster because the hottest branches come first.