unit1 mm

1. Unit-I
Microprocessors and Microcontrollers
8085 Microprocessor:
Basics of 8085 microprocessor architecture
and its functional block, 8085 microprocessor
IC pin outs and signals, addressing modes of
8085.

2. Block diagram of 8085

3. Pin diagram

4. Addressing modes in 8085
• The addressing modes in 8085 microprocessors are
instructions used to transfer data and perform
operations on them. An 8085 microprocessor uses
five addressing modes:
• Immediate addressing mode,
• Register addressing mode,
• Register indirect addressing mode,
• Direct addressing mode,
• Implicit addressing mode.

5. • The architecture of the 8085 microprocessor
consists of several key components, including
the accumulator, registers, program counter,
stack pointer, instruction register, flags
register, data bus, address bus, and control
bus. The accumulator is an 8-bit register that
is used to store arithmetic and logical results.

6. • In its simplest form a multi-chip fixed
architecture microprocessor consists of three
circuits:
• (i) The central processor which may have 8-,
12- or 16-bit capability
• (ii) The microprogram sequence control logic
• (iii) The microprogram ROM.