十六进制
3.A sequence of octal or hexadecimal digits is terminated by the first character that is not an octal digit or a hexadecimal digit, respectively.
4.The hexdec() function converts a hexadecimal number to a decimal number.
5.The dechex() function converts a decimal number to a hexadecimal number.
6.Transformation Discussion Between Hexadecimal and BCD in Single Chip Computer
9.Add this class to your project to give you the ability to convert between Hex, Dec and Binary numbers in any way you please. Sample code is provided.
10.A group of four, i.e., four pulses used to express a decimal digit or a hexadecimal digit.

