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8085 Instructions - Datatransfer

DATA TRANSFER INSTRUCTIONS

 Opcode  Operand Explanation of Instruction
 Description
 MOV

 Rd, Rs

M, Rs

Rd, M

Copy from source(Rs) to destination(Rd)

 This instruction copies the contents of the source register into the destination register; the contents of the source register are not altered. If one of the operands is a memory location, its location is specified by the contents of the HL registers.

Example: MOV B, C or MOV B, M

 MVI

 Rd, data

M, data

Move immediate 8-bit

The 8-bit data is stored in the destination register or memory. If the operand is a memory location, its location is specified by the contents of the HL registers.

Example: MVI B, 57H or MVI M, 57H

 LDA  16-bit address Load accumulator

The contents of a memory location, specified by a 16-bit address in the operand, are copied to the accumulator. The contents of the source are not altered.

Example: LDA 2034H

 LDAX  B/D Reg. pair Load accumulator indirect

The contents of the designated register pair point to a memory location. This instruction copies the contents of that memory location into the accumulator. The contents of either the register pair or the memory location are not altered.

Example: LDAX B

 LXI  Reg. pair, 16-bit data Load register pair immediate

The instruction loads 16-bit data in the register pair designated in the operand.

Example: LXI H, 2034H or LXI H, XYZ

 LHLD  16-bit address Load H and L registers direct

 The instruction copies the contents of the memory location pointed out by the 16-bit address into register L and copies the contents of the next memory location into register H. The contents of source memory locations are not altered.

Example: LHLD 2040H

 STA  16-bit address 16-bit address

The contents of the accumulator are copied into the memory location specified by the operand. This is a 3-byte instruction, the second byte specifies the low-order address and the third byte specifies the high-order address.

Example: STA 4350H

 STAX  Reg. pair Store accumulator indirect

The contents of the accumulator are copied into the memory location specified by the contents of the operand (register pair). The contents of the accumulator are not altered.

Example: STAX B

 SHLD  16-bit address Store H and L registers direct

The contents of register L are stored into the memory location specified by the 16-bit address in the operand and the contents of H register are stored into the next memory location by incrementing the operand. The contents of registers HL are not altered. This is a 3-byte instruction, the second byte specifies the low-order address and the third byte specifies the high-order address.

Example: SHLD 2470H

XCHG
 none Exchange H and L with D and E

The contents of register H are exchanged with the contents of register D, and the contents of register L are exchanged with the contents of register E.

Example: XCHG

 SPHL none
Copy H and L registers to the stack pointer

The instruction loads the contents of the H and L registers into
the stack pointer register, the contents of the H register provide the high-order address and the contents of the L register provide the low-order address. The contents of the H
and L registers are not altered.

Example: SPHL

 XTHL  none Exchange H and L with top of stack

The contents of the L register are exchanged with the stack location pointed out by the contents of the stack pointer register. The contents of the H register are exchanged with the next stack location (SP+1); however, the contents of the stack pointer register are not altered.

Example: XTHL

 PUSH  Reg. pair Push register pair onto stack

The contents of the register pair designated in the operand are copied onto the stack in the following sequence. The stack pointer register is decremented and the contents of the highorder register (B, D, H, A) are copied into that location. The stack pointer register is decremented again and the contents of the low-order register (C, E, L, flags) are copied to that location.

Example: PUSH B or PUSH A

 POP  Reg. pair Pop off stack to register pair

The contents of the memory location pointed out by the stack pointer register are copied to the low-order register (C, E, L, status flags) of the operand. The stack pointer is incremented by 1 and the contents of that memory location are copied to the high-order register (B, D, H, A) of the operand. The stack pointer register is again incremented by 1.

Example: POP H or POP A

OUT
 8-bit port address Output data from accumulator to a port with 8-bit address

 The contents of the accumulator are copied into the I/O port specified by the operand.

Example: OUT F8H

 IN  8-bit port address Input data to accumulator from a port with 8-bit address

The contents of the input port designated in the operand are read and loaded into the accumulator.

Example: IN 8CH

Other Instructions:

Arithmetic Instructions

Branching Instructions

Logical Instructions

Control Instructions