Immediate addressing mode in 8085 Microprocessor

MicrocontrollerMicroprocessor8085

In this mode, the 8/16-bit data is specified in the instruction itself as one of its operand. For example MVI E, ABH: means ABH is copied into register A. Here the operand is immediately available in the instruction.

  • MVI E ABH



Before
After
(A)
Any value
ABH

As example, if we consider instruction MVI E, ABH then it means that ABH will be moved or copied to the register E. And, as a result, the previous value of E will get overwritten.

Address
Hex Codes
Mnemonic
Comment
2000
1E
MVI E, ABH
E ← ABH
2001
AB

ABH as operand

This instruction will have seven T-states as shown below.

Summary  − So this instruction MVI E, ABH requires 2-Bytes, 2-Machine Cycles (Opcode Fetch and Memory Read) and 7T-States for execution as shown in the timing diagram. 

raja
Published on 04-Jan-2019 17:21:13
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