Which of the following instruction is a six byte instruction?
This instruction format can be coded from 1 to 6 bytes depending upon the addressing modes used for instructions. The Opcode stands for Operation Code. Every Instruction has a unique 6-bit opcode. For example, the opcode for MOV is 100010….Instruction Format in 8086 Microprocessor.
| REG Code | Register Selected |
|---|---|
| 1 1 1 | BH DI |
Why the size of 8086 is 6 bytes in queue?
8086 Queue is only Six Byte long: This is because the longest instruction in the instruction set of 8086 is six byte long. Hence with a six byte long queue it is possible to pre-fetch even the longest instruction in the main program.
Why is the size of queen in 8086 is 6 bytes Mcq?
Because the longest instruction in 8086 is 6 byte long. Hence it is possible to prefetch even the longest instruction in the instruction set.
What is the maximum size of an instruction in 8086?
The max size is 64K. There is no minimum – you can use only first byte, but the segment is always 64K. Maybe the exception are the last segments – the latest (0xFFFF) is 16 bytes, before the latest are 32, 48, 64 bytes… Generally, 8086 segments are method for addressing of more than 64K with 16 bit address registers.
How many bytes are present in the 8085 instruction?
In 8085, the length is measured in terms of “byte” rather then “word” because 8085 microprocessor has 8-bit data bus. Three types of instruction are: 1-byte instruction, 2-byte instruction, and 3-byte instruction. In 1-byte instruction, the opcode and the operand of an instruction are represented in one byte.
How many instructions are there in 8086?
117 basic instructions
There are 117 basic instructions in the instruction set of 8086.
What is an instruction byte?
Three-byte instruction is the type of instruction in which the first 8 bits indicates the opcode and the next two bytes specify the 16-bit address. The low-order address is represented in second byte and the high-order address is represented in the third byte.
What is the size of instruction byte queue in 8086?
6-bytes
Ans. The instruction queue is 6-bytes in length, operates on FIFO basis, and receives the instruction codes from memory. BIU fetches the instructions meant for the queue ahead of time from memory.
How many 16-bit registers are there in 8086?
The 8086 has eight more or less general 16-bit registers (including the stack pointer but excluding the instruction pointer, flag register and segment registers). Four of them, AX, BX, CX, DX, can also be accessed as twice as many 8-bit registers (see figure) while the other four, SI, DI, BP, SP, are 16-bit only.
What is the size of queue in 8086 microprocessor?
The instruction queue is 6-bytes in length, operates on FIFO basis, and receives the instruction codes from memory.
What is the name of 16-bit register in 8085?
Stack Pointer (SP)
Stack Pointer (SP) The stack pointer is also a 16-bit register used as a memory pointer. It points to a memory location in R/W memory, called the stack.
What are 8086 instructions?
The 8086 provides some instructions which handle string operations such as string movement, comparison, scan, load and store. Moves 8-bit or 16-bit data from the memory location(s) addressed by SI register to the memory location addressed by DI register.
Which is a 3 byte instruction?
In a 3-byte instruction, the first byte specifies the opcode, and the following two bytes specify the 16-bit address. The 2nd byte holds the low order address. The 3rd-byte holds the high order address. Instructions require three memory locations to store the single byte in the memory.
What is 3 byte instruction example?
Three-byte instructions If a 16-bit numeral is present in the instruction then that instruction will be of three-byte. Here, the numeral may be a data or an address, for example, in LXI H,3500H and STA 2500H, etc.
What is 8-bit and 16-bit microprocessor?
The most popular to those who are just starting out are 8 bit and 16 bit microcontrollers. The main difference between 8 bit and 16 bit microcontrollers is the width of the data pipe. As you may have already deduced, an 8 bit microcontroller has an 8 bit data pipe while a 16 bit microcontroller has a 16 bit data pipe.
What is instruction explain any 6 instruction set of 8085?
Arithmetic Group
| Instruction Set | Explanation | Flags |
|---|---|---|
| ADI data [A] ← [A] + data | Add immediate data to accumulator | All |
| ACI data [A] ← [A] + data + [CS] | Add with carry immediate data to accumulator | All |
| DAD rp [H-L] ←[H-L] + [rp] | Add register paid to H-L pair | CS |
| SUB r [A] ←[A]-[r] | Subtract register from accumulator | All |
Which are 16-bit registers?
16-bitEdit The registers found on the 8086 and all subsequent x86 processors are the following: AX, BX, CX, DX, SP, BP, SI, DI, CS, DS, SS, ES, IP and FLAGS. These are all 16 bits wide.
Which is 2 byte instruction?
Two-byte instruction is the type of instruction in which the first 8 bits indicates the opcode and the next 8 bits indicates the operand. Example-1: Task- Load the hexadecimal data 32H in the accumulator.
What is a 1-byte instruction?
1. One-byte instructions – In 1-byte instruction, the opcode and the operand of an instruction are represented in one byte. Example-1: Task- Copy the contents of accumulator in register B.