Data Transfer Instructions in 8085 Microprocessor
S.No | Instruction | Example |
1. | Move – To copy a data from source to destination register. MOV Rd, Rs MOV M, Rs MOV Rd, M | MOV D, C MOV M, B MOV B, M |
This instruction MOV Ax,Bx copies the contents of the source register into the destination register. This instruction doesn’t alter the contents of the source register. This instruction is Mainly used for transferring the same data from one register to the other. | ||
2. | Move immediate 8-bit MVI Rd, data MVI M, data | MVI B, 50H MVI M, 50H |
In order to store an 8-bit data in the destination register, the instruction MVI Rd, data is used. The destination register or memory stores the 8-bit data. | ||
3. | Load accumulator direct LDA 16-bit address of a memory location, | LDA 5000H |
The contents specified by a 16-bit address of a memory location in the operand, are copied to the accumulator. | ||
4. | Load accumulator indirect LDAX Reg. pair | LDAX B LDAX D |
The contents to a memory location from the designated register pair point. This instruction is usually used to copy the contents of that memory location into the accumulator. | ||
5. | Load register pair immediate LXI Reg. pair, 16-bit data | LXI B, 5000H LXI D, 5000H LXI H, 5000H LXI SP, 5000H |
The instruction’ Load register pair immediate’ loads 16-bit data in the register pair selected in the operand. It is usually represented as LXI D, 5000H | ||
6. | Load H and L registers direct LHLD 16-bit address | LHLD 5000H |
The instruction ‘LHLD 16-bit address ‘copies the contents of the memory location pointed by the 16-bit address into register L and copies the contents of the next memory location into register H. | ||
7. | Store accumulator direct STA 16-bit address | STA 5000H |
‘Store accumulator direct’: In this type of instruction, To the memory location specified by the operand, the contents of the accumulator are copied. | ||
8. | Store accumulator indirect STAX Rx | STAX B STAX D |
‘Store accumulator indirect’ instruction set is used for copying the contents of the accumulator to the memory location specified by register pair. In other words, we can say that: The contents of the accumulator are copied into the memory location specified by the contents of the operand (register pair). | ||
9. | Store H and L registers direct SHLD 16-bit address | SHLD 5000H |
The data’s of register L are store to the memory location by the 16 bit address in the operand. Datas of H register are stored into the next location of memory. | ||
10. | Exchange H and L with D and E XCHG | XCHG |
The instruction ‘Exchange H and L with D and E’ represents: The contents of register H and register D are exchanged with eachother. The contents of register L and register E are exchanged with each other. | ||
11. | Copy H and L registers to the stack pointer SPHL | SPHL |
‘Copy H and L registers to the stack pointer SPHL’ represents: The contents of the H and L registers are loaded into the stack pointer register. | ||
12. | Exchange H and L with top of stack pointer XTHL | XTHL |
‘Exchange H and L with top of stack pointer XTHL’ represents: The contents of the L register are exchanged with the stack location pointed by the contents of the stack pointer register(SP Register). The data stored in the H register are exchanged with the next stack location (SP+1). | ||
13. | Push register pair onto stack PUSH Reg. pair (PSW ‘Processor Status Word’ means Accumulator and Flag register) | PUSH B PUSH D PUSH H PUSH PSW |
‘Push register pair onto stack’ usually denotes: The data of the register pair assigned in the operand are copied to the stack. | ||
14. | Pop off stack to register pair POP Reg. pair | POP B POP D POP H POP PSW |
‘Pop off stack to register pair’ instruction set - The contents of the memory location pointed out by the stack pointer register are copied to registers specified. | ||
15. | Output data from accumulator to a port with 8-bit address OUT 8-bit port address | OUT 50H |
‘OUT 8-bit port address ‘ denotes: - The contents of the accumulator are copied into the I/O port specified by the operand. | ||
16. | Input data to accumulator from a port with 8-bit address IN 8-bit port address | IN 50H |
‘IN 8-bit port address ‘ instruction represents:- The contents of the input port designated in the operand are read and loaded into the accumulator. |
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