Features of Intel 8085 microprocessor

Features of Intel 8085 microprocessor:

The features of Intel 8085 microprocessor are as follows:

Breadboard  Atmel AVR microprocessor project.
Breadboard Atmel AVR microprocessor project. (Photo credit: thepodger)

1)      8085 microprocessor is an 8 bit microprocessor. I.e. it can accept or provide 8 bit data simultaneously.

2)      8085 microprocessor is a single chip, NMOS device implemented with 6200 transistors.

3)      8085 microprocessor requires a single +5V DC power supply.

4)      8085 microprocessor provides on chip clock generator, therefore there is no need of external clock generator, but it requires external tuned circuit like LC, RC or crystal.

5)      8085 microprocessor requires two phase, 50% duty cycle, TTL clock. These clock signals are generated by an internal clock generator (refer following figure).

2 Phase TTL clock
2 Phase TTL clock

6)      The maximum clock frequency of 8085 microprocessor is 3MHz where as minimum clock frequency is 500 KHz.

7)      8085 provides 74 instructions with the following addressing modes:

  • register
  • direct
  • immediate
  • indirect
  • implied.

8)      The data bus is multiplexed with the address bus, hence it requires external hardware to separate data lines from address lines (this is one of the disadvantage of 8085).

9)      8085 microprocessor provides 16 address lines, therefore it can access 2^16 = 64K bytes of memory.

10)   It generates 8 bit I/O address, hence it can access 2^8 = 256 input ports and 256 output ports.

11)   It performs the following arithmetic and logical operations.

  • 8 bit, 16 bit binary addition
  • 2 digit BCD addition
  • 8 bit binary subtraction
  • logical AND, OR, EXOR
  • complement and shift operations.

12)   8085 microprocessor has five hardware interrupts: TRAP, RST 5.5, RST 6.5, RST 7.5, INTR

13)   The hardware interrupt capability of 8085 microprocessor can be increased by providing external hardware.

14)   8085 microprocessor has capability to share its bus with external bus controller (direct memory access controller); for transferring large amount of data from memory to I/O and vice versa.

15)   8085 microprocessor provides one accumulator, one flag register, 6 general purpose registers and two special purpose registers.

16)   It provides status for advanced control signals. (Advanced control signals are used in large systems).

17)   8085 microprocessor can be used to implement three chip microcomputer (8085, 8155, 8355)

18)   8085 microprocessor provides two serial I/O lines which are SOD and SID; it means, serial peripherals can be interfaced with 8085 microprocessor directly.

You may also like:

Tags: Features of Intel 8085 microprocessor.

Also read:  Four Point Starter - best explained

Leave a Reply