Pseudo-operation commands in assembly language
DB is a pseudo-operation command in assembly language, which is used to define the number of bytes occupied by operands.
role
Here B is short for byte, so each operand defined by this pseudo-operation takes 1 byte (8 bits).
such as
At this time, each character in the string \"HELLO\" will occupy 1 byte, 51 MCU, used to define the content of the byte. The DB instruction initializes the code space in bytes of the value of the expression.