DATA TRANSFER INSTRUCTIONS -8085 Microprocessor

Opcode     Operand

Copy from source to destination

Description
MOV         Rd, Rs This instruction copies the contents of the source
M, Rs register into the destination register; the contents of
Rd, M Move immediate 8-bit 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 The 8-bit data is stored in the destination register or
M, data

Load accumulator

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 indirect

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 register pair immediate

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 H and L registers direct

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 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
Store accumulator direct  
STA           16-bit address

Store accumulator indirect

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 H and L registers direct

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

Exchange H and L with D and E

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 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

Copy H and L registers to the stack pointer

SPHL none 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

Exchange H and L with top of stack

XTHL none 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 register pair onto stack  
PUSH        Reg. pair

Pop off stack to register pair

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 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

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

OUT 8-bit port address The contents of the accumulator are copied into the I/O port specified by the operand. Example:  OUT F8H

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

IN 8-bit port address The contents of the input port designated in the operand are read and loaded into the accumulator. Example:  IN 8CH

PhD researcher at Friedrich-Schiller University Jena, Germany. I'm a physicist specializing in theoretical, computational and experimental condensed matter physics. I like to develop Physics related apps and softwares from time to time. Can code in most of the popular languages. Like to share my knowledge in Physics and applications using this Blog and a YouTube channel.



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