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Features of 8085 Microprocessor

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  • 8085 MPU is an 8-bit microprocessor i.e. it can accept, process and provide 8-bit data.
  • It operates on +5V power supply connected at Vcc.
  • Power supply ground is connected to Vss.
  • It has 8 data lines (D0 - D7).
  • It has 16 address lines (A0 - A15). It can access 2^16 = 64K of memory.
  • It has 8 bit I/O address. It can access 2^8 = 256 I/O ports.
  • It operates on clock cycle with 50% duty cycle.
  • It operates with a 3MHz clock frequency.
  • The lower 8-bit address bus (A0 - A7) and data bus (D0 - D7) are multiplexed to reduce number of external pins.
  • It has 8-bit accumulator, flag register, instruction register, six 8-bit general purpose registers (B, C, D, E, H and L) and two 16-bit registers (SP and PC).
  • It has five hardware interrupts. They are TRAP, RST 7.5, RST 6.5, RST 5.5 and INTR.
  • It has serial I/O control which allows serial communication.
  • It has control signals (IO/M, RD, WR) to control bus cycles.
  • It has five addressing modes. They are: immediate, register, direct, indirect and implied.
  • It has powerful instruction set that can do various arithmetic operations and some logical operations.
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