Part of the programming flexibility for each microprocessor is the number and different kind of ways the programmer can refer to data stored in the memory. The different ways that a microprocessor can access data are referred to as addressing modes. The 5 Addressing Modes of 8085 are :
1.Immediate addressing mode :
In an immediate addressing mode, 8 or 16 bit data can be specified as a part of instruction. In 8085, the instructions having ‘I’ letter fall under this category. ‘I’ indicates immediate addressing mode.
2.Register Addressing Mode :
The register addressing mode specifies the source operand, destination operand, or both to be contained in an 8085 registers. This results in faster execution, since it is not necessary to access memory locations for operands.
3.Direct Addressing Mode :
The direct addressing mode specifies the 16 bit address of the operand within the instruction itself. The second and third bytes of instruction contain this 16 bit address.
4.Indirect Addressing Mode :
In indirect addressing mode, the memory address where the operand located is specified by the contents of a register pair.
5.Implied Addressing Mode :
In implied addressing mode, opcode specifies the address of the operands.