Command List of 8085

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  • Topic: Instruction set, X86, Control flow
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  • Published : May 1, 2013
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Command List

Data Transfer Group:
The data transfer instructions move data between registers or between memory and registers.

MOV           Move
MVI           Move Immediate
LDA           Load Accumulator Directly from Memory STA           Store Accumulator Directly in Memory LHLD          Load H & L Registers Directly from Memory SHLD          Store H & L Registers Directly in Memory

An 'X' in the name of a data transfer instruction implies that it deals with a register pair (16-bits);

LXI           Load Register Pair with Immediate data LDAX          Load Accumulator from Address in Register Pair STAX          Store Accumulator in Address in Register Pair XCHG          Exchange H & L with D & E

XTHL          Exchange Top of Stack with H & L

Arithmetic Group:
The arithmetic instructions add, subtract, increment, or decrement data in registers or memory.

ADD           Add to Accumulator
ADI           Add Immediate Data to Accumulator
ADC           Add to Accumulator Using Carry Flag
ACI           Add Immediate data to Accumulator Using Carry SUB           Subtract from Accumulator
SUI           Subtract Immediate Data from Accumulator SBB           Subtract from Accumulator Using Borrow (Carry) Flag SBI           Subtract Immediate from Accumulator Using Borrow (Carry) Flag INR           Increment Specified Byte by One

DCR           Decrement Specified Byte by One
INX           Increment Register Pair by One
DCX           Decrement Register Pair by One
DAD           Double Register Add; Add Content of Register               Pair to H & L Register Pair

Logical Group:
This group performs logical (Boolean) operations on data in registers and memory and on condition flags.

The logical AND, OR, and Exclusive OR instructions enable you to set specific bits in the accumulator ON or OFF.

ANA           Logical AND with Accumulator
ANI           Logical AND with Accumulator Using Immediate Data ORA           Logical OR with Accumulator
OR            Logical OR with Accumulator Using Immediate Data XRA           Exclusive Logical OR with Accumulator XRI           Exclusive OR Using Immediate Data

The Compare instructions compare the content of an 8-bit value with the contents of the accumulator;              
CMP           Compare
CPI           Compare Using Immediate Data

The rotate instructions shift the contents of the accumulator one bit position to the left or right:

RLC           Rotate Accumulator Left
RRC           Rotate Accumulator Right
RAL           Rotate Left Through Carry
RAR           Rotate Right Through Carry

Complement and carry flag instructions:

CMA           Complement Accumulator
CMC           Complement Carry Flag
STC           Set Carry Flag

Branch Group:
The branching instructions alter normal sequential program flow, either unconditionally or conditionally. The unconditional branching instructions are as follows:

JMP           Jump
CALL          Call
RET           Return

Conditional branching instructions examine the status of one of four condition flags to determine whether the specified branch is to be executed. The conditions that may be specified are as follows:

NZ            Not Zero (Z = 0)
Z             Zero (Z = 1)
NC            No Carry (C = 0)
C             Carry (C = 1)
PO            Parity Odd (P = 0)
PE            Parity Even (P        = 1)
P             Plus (S = 0)
M             Minus (S = 1)

Thus, the conditional branching instructions are specified as follows:

Jumps         Calls        Returns
C             CC            RC      (Carry) INC           CNC           RNC     (No Carry) JZ            CZ            RZ      (Zero) JNZ           CNZ           RNZ     (Not Zero) JP            CP            RP      (Plus) JM            CM            RM      (Minus) JPE           CPE           RPE     (Parity Even) JP0           CPO           RPO     (Parity Odd)

Two other...
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