railway system project in dbms

8085 INSTRUCTION SET
INSTRUCTION DETAILS
DATA TRANSFER INSTRUCTIONS
Opcode

Operand

Copy from source to destination
MOV
Rd, Rs
M, Rs
Rd, M

Move immediate 8-bit
MVI
Rd, data
M, data

Load accumulator
LDA
16-bit address

Load accumulator indirect
LDAX
B/D Reg. pair

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

Load H and L registers direct
LHLD
16-bit address

8085 Instruction Set

Description
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
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, 57 or MVI M, 57
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 2034 or LDA XYZ
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
The instruction loads 16-bit data in the register pair designated in the operand.
Example: LXI H, 2034
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 2040

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Store accumulator direct
STA
16-bit address

Store accumulator indirect
STAX
Reg. pair

Store H and L registers direct
SHLD
16-bit address

Exchange H and L with D and E
XCHG
none

The contents of the accumulator are copied