8051 Microcontroller

Addressing Modes :- The CPU can access data in a register or in memory or be provided as an immediate value. These various ways of accessing data are called addressing modes.       The 8051 provides a total of five distinct addressing modes.       They are as follows:-       1) Immediate addressing modes.       2) Register addressing modes.       3) Direct addressing modes.       4) Register indirect - addressing mode.       5) Indexed addressing mode. Let us study different modes with selective examples:- 1) Immediate Addressing mode:-                                     In This addressing mode, the source operated is a constant i.e. immediate data. Note that the immediate data must be preceded by the pound sign"#".        Example:-                 MOV A, # 82H                         ; load 82H into A                 MOV R4, # 100                        ; load the decimal value 100 in to R4                 MOV B, # 40H                         ; l