5.3. Bit Granularity

Every byte consists of 8 bits. Every bit has a value of 0 or 1. Here are some examples of bytes, words and double words shown as bit strings (we can also see clearly the correspondence between 4 bit sequences and hexadecimal numbers, Table 3.1):

• Byte

  C / C++: unsigned char

  Windows definitions: BYTE, UCHAR

  8 bits

  Values 0_dec - 255_dec or 0_hex - FF_hex

  Example: 12_dec 00001100_bin 0C_hex

• Word

  C / C++: unsigned short

  Windows definitions: USHORT, WORD

  16 bits

  Values 0_dec - 65535_dec or 0_hex - FFFF_hex

  Example: 0000000000001100_bin  000C_hex

• Double word

  C / C++: unsigned int, unsigned, unsigned long

  Windows definitions: DWORD, UINT, ULONG

  32 bits

  Values 0_dec - 4294967295_dec or 0_hex - FFFFFFFF_hex

  Example: 00000000000000000000000000001100_bin 0000000C_hex