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General Instruction Formats in 8086 Microprocessor
8086 Microprocessor General Instruction Formats: Here, we are going to learn about the various general instruction formats in 8086 Microprocessor.
Submitted by Uma Dasgupta, on February 10, 2020
Introduction:
In this article, we are going to discuss about the 6 general formats of instructions.
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One byte instruction:
This is only one byte long and may have implied data and register.
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Register to register:
This instruction is 2 byte long. First byte specified opcode and width(w) of opcode and second byte specified register operand and R/M field.
Here, MSB - Most significant bit and LSB - Least significant bit
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Register to/from memory with no displacement:
This format is also 2-byte form and similar to the register except the MOD field.
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Register to/from memory with displacement:
This is same as the third one having one or two additional byte for displacement.
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Immediate operand to register:
In it first byte as well as three bits from the second byte which are used for the register field. In case of register to register format is reserved for the opcode. It also contains 1 or 2 bytes of immediate data.
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Immediate Operand to memory with 16-bit displacement:
Opcode have single bit indicators their significance is as follows,
Conclusion:
In the above article, I have discussed the different instruction formats of the microprocessors briefly, with relative diagrams also. As I said earlier at the beginning of this article also that this topic of computer system organization is very important from the examination point of view and also the base of your knowledge about computer architecture. For further queries shoot your questions in the comment section below!