The Intel 8085 is an 8-bit microprocessor first made available, released in 1976, and was very important in the early days of computers. The Von Neumann architecture-based system performs arithmetic, logical, and control functions. Studying the 8085 microprocessor provides a lot of significant advantages despite being an older architecture. Some of the benefits are listed below:

1. Historical Significance: The 8085 microprocessor had major significance in the early stages of computing and the development of microprocessor technology. In 8085, it is emphasized how microprocessors have changed over time and how important they are to modern computer design.
2. Foundation of Microprocessors: The 8085 microprocessor’s architecture influenced later 8-bit CPUs. Learning the basics of architecture may help us to examine more complex microprocessors and computer systems.
3. Resource Constraints: The 8085 microprocessor operates with limited resources, such as memory and processing power. Studying its architecture can help in understanding how to optimize code and develop efficient algorithms for resource-constrained environments.
4. Conceptual Understanding: The 8085 microprocessor is simpler than modern-day CPUs. knowledge of 8085 microprocessor helps the new learners to understand microprocessors, including how instructions are processed, memory is interfaced, and I/O procedures function.
5. Stepping Stone: Learning about the 8085 microprocessor can help us to understand more complicated modern microprocessors. Furthermore, it may facilitate the initiation of several professional and hobby-related projects.

Features of 8085 Microprocessor

Features of 8085 microprocessor are given below:

1. 8-bit Data Bus: The 8085 has an 8-bit data bus, which means it can transfer 8 bits of data between the microprocessor and memory or I/O devices at a time.
2. 16-bit Address Bus: The 8085 uses a 16-bit address bus, allowing it to access up to 64 KB (216) of memory. This limitation makes it suitable for small-scale computing applications.
3. Address & Data Bus Multiplexed: In the 8085, the data bus (D0 – D7) and lower 8-bit address bus (A0 – A7) are multiplexed in order to reduce the number of external pins. However, as a result, address lines and data lines must be separated by additional hardware (Latch).
4. Single +5V Power Supply: The 8085 microprocessor operates on a single +5V power supply, making it suitable for low-power applications. Power supply is connected to Vdd and Ground is connected to Vss.
5. Clock Frequency: The 8085 typically operates at a clock frequency of 3 MHz. 8085A-2 version can operate at a maximum frequency of 5 MHz. It functions on a 50% duty cycle clock cycle.
6. Clock Generator: It has on chip clock generator. This internal clock generator requires a calibrated LC, RC, or crystal circuit. The internal clock generator generates clock signal by dividing oscillator frequency by two.
7. Registers: It has six general-purpose registers, these are register B, C, D, E, H, and L, which can be used individually (as 8-bit) or in pairs (as 16-bit) to perform various arithmetic and logical operations.
8. Accumulator: The accumulator (A register) is a special 8-bit register used for arithmetic and logic operations. Most arithmetic operations involve the accumulator.
9. Flag Register: The flag register consists of various flags that are set or reset based on the result of the previous operation. The flags include Carry (CY), Auxiliary Carry (AC), Sign (S), Zero (Z), Parity (P), and Overflow (V).
10. Stack Pointer (SP): The 8085 has a 16-bit stack pointer, which points to the memory location where the stack is currently located. The stack is used for storing return addresses and local data during subroutine calls.
11. Program Counter (PC): The program counter is a 16-bit register that holds the memory address of the next instruction to be executed.
12. Instruction Set: The 8085 microprocessor supports 274 instructions, including arithmetic operations (addition, subtraction, etc.), logical operations (AND, OR, XOR), data transfer operations, branching instructions, and more.
13. Interrupts: The 8085 supports five hardware interrupts, these are TRAP, RST 7.5, RST 6.5, RST 5.5, and INTR. These interrupt lines allow external devices to request attention from the microprocessor.
14. Serial Input/Output Ports: The 8085 has two serial I/O ports (SID and SOD) for serial communication with peripherals like keyboards, displays, and other devices.
15. Control Signal: It provides control signals (IO/M(low), RD(low), WR(low)) to control the bus cycle, and hence external bus controller is not required.
16. DMA Controller: The 8085 is capable of sharing the system interface with Direct Memory Access controller. This feature permits the transmission of large amounts of data at high velocities from I/O devices to memory or from I/O devices.