This is for floating point conversions. Custom is for setting desired exponent widths "ew" and mantissa widths "mw". The output is given in decimal and coloured binary beneath. If "ew" and "mw" are empty the hexadecimal input asssume F16, F32 or F64 inputs
This returns the decimal value for an input in twos complement form
This just converts hexadecimal to binary for quick checks