8085 Instruction Set & T-Clock Cycles

 8085 Instruction Set & T-Clock Cycles


Symbol
Meaning
A
Accumulator
B,C,D, E,H,L
8085 8-Bit register (internal registers)
F
Represents the flag register
M
The 16-bit memory address currently held by the register pair H and L
byte
An 8-bit data quantity
port
An 8-bit I/O port address
r, rl, r2
8085 8-Bit register (One of the registers A, B, C, D, E, H, L)
rp





One of the following register pairs
B represents the register pair Band C
D represents the register pair D and E
H represents the register pair Hand L
PSW represents the register pair A and F
SP represents the 16-bit stack pointer
PC
The 16-bit program counter
CY
Carry flag
P
Parity flag
AC
Auxiliary carry flag
Z
Zero flag
S
Sign flag


MOVE, LOAD AND STORE INSTRUCTION SET

Mnemonic
T- Cycles
Control Signals
MOV  rl, r2
4
RD,
MOV M, r
7
RD,WR
MOV r, M
7
RD,RD
MVI r, 8-bit Data
7
RD,RD
MVI M, 8-bit Data
10
RD,RD,WR
LXI B, 16-bit Data
10
RD,RD,RD
LXI D, 16-bit Data
10
RD,RD,RD
LXI H, 16-bit Data
10
RD,RD,RD
LXI SP, 16-bit Data
10
RD,RD,RD
STAX B
7
RD, WR
STAX D
7
RD, WR
LDAX B
7
RD, RD
LDAX D
7
RD, RD
STA 16-bit Data
13
RD, RD, RD, WR
LDA 16-bit Data
13
RD, RD, RD,RD
SHLD 16-bit Data
16
RD, RD, RD, RD,WR
LHLD 16-bit Data
16
RD, RD, RD, RD, RD
XCHG
4
RD

ADD, SUBTRACT, INCREMENT AND DECREMENT INSTRUCTION SET

Mnemonic
T- Cycles
Control Signals
ADD r
4
RD
ADC r
4
RD
ADD M
7
RD,RD
ADC M
7
RD, RD
ADI 8-bit Data
7
RD, RD
ACI 8-bit Data
7
RD, RD
DAD B
10
RD, RD, RD
DAD D
10
RD, RD,RD
DAD H
10
RD, RD, RD
DAD SP
10
RD, RD, RD
SUB r
4
RD
SBB r
4
RD
SUB M
7
RD,RD
SBB M
7
RD, RD
SUI 8-bit Data
7
RD, RD
SBI 8-bit Data
7
RD, RD
INR r
4
RD
DCR r
4
RD
INR M
10
RD,RD,RD,WR
DCRM
10
RD,RD,RD,WR
INX B
6
RD
INX D
6
RD
INX H
6
RD
INX SP
6
RD
DCX B
6
RD
DCX D
6
RD
DCX H
6
RD
DCX SP
6
RD

JUMP INSTRUCTION SET

Mnemonic
T- Cycles
Control Signals
JMP 16-bit Data
10
RD,RD,RD
JC 16-bit Data
7/10
RD,RD,RD
JNC16-bit Data
7/10
RD,RD,RD
JZ 16-bit Data
7/10
RD,RD,RD
JNZ 16-bit Data
7/10
RD,RD,RD
JP 16-bit Data
7/10
RD,RD,RD
JM 16-bit Data
7/10
RD,RD,RD
JPE 16-bit Data
7/10
RD,RD,RD
JPO 16-bit Data
7/10
RD,RD,RD
PCHL
6
RD

STACK, CALL OPERATIONS & RETURN INSTRUCTION SET

Mnemonic
T- Cycles
Control Signals
PUSH B
12
RD, RD, WR
PUSH D
12
RD,RD,WR
PUSH H
12
RD, RD, WR
PUSH PSW
12
RD,RD,WR
POP B
10
RD,RD,RD
POP D
10
RD,RD,RD
POP H
10
RD,RD,RD
POP PSW
10
RD,RD,RD
XTHL
16
RD,RD,RD,WR,WR
SPHL
6
RD
CALL 16-bit Data
18
RD,RD,RD,RD,RD,RD
CC  16-bit Data
9/18
RD,RD,RD,RD,RD,RD
CNC  16-bit Data
9/18
RD,RD,RD,RD,RD,RD
CZ  16-bit Data
9/18
RD,RD,RD,RD,RD,RD
CNZ  16-bit Data
9/18
RD,RD,RD,RD,RD,RD
CP  16-bit Data
9/1 8
RD,RD,RD,RD,RD,RD
CM  16-bit Data
9/18
RD,RD,RD,RD,RD,RD
CPE  16-bit Data
9/18
RD,RD,RD,RD,RD,RD
CPO  16-bit Data
9/18
RD,RD,RD,RD,RD,RD
RET 16-bit Data
10
RD,RD,RD
RC 16-bit Data
6/12
RD,RD,RD
RNC 16-bit Data
6/12
RD,RD,RD
RZ 16-bit Data
6/12
RD,RD,RD
RNZ 16-bit Data
6/12
RD,RD,RD
RP 16-bit Data
6/12
RD,RD,RD
RM 16-bit Data
6/12
RD,RD,RD
RPE 16-bit Data
6/12
RD,RD,RD
RPO 16-bit Data
6/12
RD,RD,RD

LOGICAL, INTERRUPTMASK, ROTATE, SPECIALS, CONTROL, RESTART
& INPUT/OUTPUT INSTRUCTION SET

Mnemonic
T- Cycles
Control Signals
ANA r
4
RD
XRA r
4
RD
ORA r
4
RD
CMP r
4
RD
ANAM
7
RD,RD
XRA M
7
RD,RD
ORAM
7
RD,RD
CMP M
7
RD,RD
ANI 8-bit Data
7
RD,RD
XRI 8-bit Data
7
RD,RD
ORI 8-bit Data
7
RD,RD
CPI 8-bit Data
7
RD,RD
DAA
4
RD,RD
RIM
4
RD,RD
SIM
4
RD
DI
4
RD
EI
4
RD
RLC
4
RD
RRC
4
RD
RAL
4
RD
RAR
4
RD
CMA
4
RD
STC
4
RD
CMC
4
RD
DAA
4
RD
NOP
4
RD
HLT
5
XX
IN 8-bit Data
10
RD, RD
OUT 8-bit Data
10
RD, WR
RST
12
XX
REFERENCES
1.     R. S. Gaonkar, Microprocessor Architecture, Programming, and Applications with the 8085, Fifth Edition, Penram International Publishing (India) Private Limited.
2.     S Ghoshal, Microprocessor Based System Design, Macmillan India Limited, 1996
3.     M. Mano, Digital Logic and Computer Design, Prentice – Hall India
4.     B. Ram - Fundamentals of Microprocessor and Microcontrollers
5.     “Microprocessors: Principles and Applications” by A Pal
6.     “Microprocessors and Microcontrollers : Architecture, Programming and Interfacing Using 8085, 8086 and 8051” by Soumitra Kumar Mandal
7.     “Introduction to Microprocessors and Microcontrollers” by Crisp John Crisp
8.     “Microprocessors And Microcontrollers” by A Nagoor Kani
9.     “Microprocessors And Microcontrollers : Architecture, Programming and System Design 8085, 8086, 8051, 8096” by KRISHNA KANT
10. “8 - Bit Microprocessor” by Vibhute

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