WHAT IS TIMING DIAGRAM OF 8085 MICROPROCESSOR

In this tutorial we are going to learn about WHAT IS TIMING DIAGRAM OF 8085 MICROPROCESSOR

It is a pictorial representation of execution of an instruction in the processor. operations in the microprocessor like memory read, memory write, i/o read, i/o write are known as machine cycles.

T-STATE- IT is a subdivision of an operation performed in one clock period.

   MACHINE CYCLES- IT is defined as time required for accessing the operands or data from memory or i/o devices.one machine cycle may contain 3 to 6t-states

   INSTRUCTION CYCLES- it is the total time required for the execution of one complete instruction.one instruction cycles may contain 1-5 machine cycle. the maximum no of t-states possible for an instruction in 8085 is 18

FOR 8085 MICROPROCESOR

     mini. number of t-state for opcode fetch~ 4t-state

     max. number of  t-state for opcode fetch ~6 t-state

     min. number of t-states for a machine cycle~ 3 t-state

     max. number of t-states for a machine cycle~ 6 t-state

     min. number of t-states for an instruction~ 4 t-state

     max. number of t-states for an instructor~ 18 t-state

     min. number of machine cycle for an instructor~ 1machine cycle

     max. number of machine cycle for an instructor~ 5 machine cycle

   TOTAL EXECUTION TIME – CLOCK PERIOD * NO. OF T-STATE* COUNT VALUE

   COUNT VALUE- how many time the instruction is executing except for opcode fetch the remaining machine cycles will have three t-state excising opcode from the memory is known as opcode fetch reading data/ operand from the memory is known as memory read operation

   INSTRUCTION SET CLASSIFICATION

   instruction are classified into two types

   1 according to type of operation

   2 according to length of instruction

  DATA TRANSFER OR COPY INSTRUCTIONS

   in this group of instruction,the data is transferred from one location known as source to another location known as destinator.

  it may be in b/w

  1 register to register

  2 register to memory

  3 register to i/o

  4 register to data

  ARITHMATIC INSTRUCTION

  the various arithmatic operations are addition,subtraction,increment and decrement

  LOGICAL INSTRUCTION

  the various logical operators are AND,OR,XOR.

  BRANCHING INSTRUCTION

  in this group,the control of the program may be transferred from one location to another.conditionally or unconditionally.

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