Post on 08-Apr-2015
description
8085 Instruction Set
*
*
*Move Immediate
*It loads the 8-bit data(byte) into the register specified.
*This is the 2 byte instruction.
*Example: MVI A,82H
MVI B,37H
*
*Load register pair immediately.
*Similar to MVI instruction.
*It loads the data or address in register pairs or stack pointer
register.
*It is 3 byte instruction.
*Example: LXI H,2050H
Address Op-
code
Operand Hex
code
8000 LDA 2050H 3A,50,
20
8003 HLT 76
Address Op-
code
Operand Hex
code
8000 LXI B,2050H 01,50,
20
8003 LDAX B 0A
8004 HLT 76
*
LDA
16-bit data byte
3
Direct
memory location
specified by contents
of register pairs
Accumulator
LDAX
Rp (B/D register pair)
1
Indirect
memory location
specified by 16-bit
address
Accumulator
*
Op-Code
operand
Bytes
Addressing modes
Transfer from
Transfer to
1. Stands for Store Accumulator Direct
2. The contents of accumulator are
copied to a memory location
specified by the operand.
3. No flags are affected.
Example: STA 2050H
Op-code Operand Bytes
STAX 16-bit 3
1. Stands for Store Accumulator Direct
2. The contents of accumulator are copied to a memory location specified by the contents of the operand (register pair).
3. No flags are affected.
Example: STAX B
This instruction is similar to move A, m except it uses the content BC or DE as memory pointers.
Op-code Operand Bytes
STAX Rp (B/D register
pair)
3
* Ranjan Yadav
* Ashish Rauniyar
* Chandan Prasad Gupta
* Rabin Bhandari
* Mikesh Khanal
*