MCS-48 System Detailed Opcode Information

MCS-48 instruction set op codes (A instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
ADD A,RN	01101nnn	1	1
ADD A,@R	0110000r	1	1
ADD A,#DATA	03 MM	2	2
ADDC A,RN	01111nnn	1	1
ADDC A,@R	0111000r	1	1
ADDC A,#DATA	13 MM	2	2
ANL A,RN	01011nnn	1	1
ANL A,@R	0101000r	1	1
ANL A,#DATA	53 MM	2	2
ANL PORT,#DATA	100110pp	2	2
ANL PORT,#DATA	MM	2	2
ANLD EP,A	100111ee	1	2

MCS-48 instruction set op codes (C instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
CALL ADDR	xxx10100	2	2
CALL ADDR	XX	2	2
CLR A	27	1	1
CLR C	97	1	1
CLR F1	A5	1	1
CLR F0	85	1	1
CPL A	37	1	1
CPL C	A7	1	1
CPL F0	95	1	1
CPL F1	B5	1	1

MCS-48 instruction set op codes (D instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
DA A	57	1	1
DEC A	07	1	1
DEC RN	11001nnn	1	1
DIS I	15	1	1
DIS TCNTI	35	1	1
DJNZ RN,ADDR8	11101nnn	2	2
DJNZ RN,ADDR8	XX	2	2

MCS-48 instruction set op codes (E instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
EN I	05	1	1
EN TCNTI	25	1	1
ENT0 CLK	75	1	1

MCS-48 instruction set op codes (I instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
IN A,PN	000010qq	1	2
INC A	17	1	1
INC RN	00011nnn	1	1
INC @R	0001000r	1	1
INS A,BUS	08	1	2

MCS-48 instruction set op codes (J instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
JBb ADDR8	bbb10010	2	2
JBb ADDR8	XX	2	2
JC ADDR8	F6 XX	2	2
JF0 ADDR8	B6 XX	2	2
JF1 ADDR8	76 XX	2	2
JMP ADDR	xxx00100	2	2
JMP ADDR	XX	2	2
JMPP @A	B3	1	2
JNC ADDR8	E6 XX	2	2
JNI ADDR8	86 XX	2	2
JNT0 ADDR8	26 XX	2	2
JNT1 ADDR8	46 XX	2	2
JNZ ADDR8	96 XX	2	2
JTF ADDR8	16 XX	2	2
JT0 ADDR8	36 XX	2	2
JT1 ADDR8	56 XX	2	2
JZ ADDR8	C6 XX	2	2

MCS-48 instruction set op codes (M instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
MOV A,#DATA	23 MM	2	2
MOV A,PSW	C7	1	1
MOV A,RN	11111nnn	1	1
MOV A,@R	1111000r	1	1
MOV A,T	42	1	1
MOV PSW,A	D7	1	1
MOV RN,A	10101nnn	1	1
MOV RN,#DATA	10111nnn	2	2
MOV RN,#DATA	MM	2	2
MOV @R,A	1010000r	1	1
MOV @R,#DATA	1011000r	2	2
MOV @R,#DATA	MM	2	2
MOV T,A	62	1	1
MOVD A,EP	000011ee	1	2
MOVD EP,A	001111ee	1	2
MOVP A,@A	A3	1	2
MOVP3 A,@A	E3	1	2
MOVX A,@R	1000000r	1	2
MOVX @R,A	1001000r	1	2

MCS-48 instruction set op codes (N,O instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
NOP	00	1	1
ORL A,RN	01001nnn	1	1
ORL A,@R	0100000r	1	1
ORL A,#DATA	43 MM	2	2
ORL PORT,#DATA	100010pp	2	2
ORL PORT,#DATA	MM	2	2
ORLD EP,A	100011ee	1	2
OUTL BUS,A	02	1	2
OUTL PN,A	001110qq	1	2

MCS-48 instruction set op codes (R-X instructions)
Instruction	Op Code	Bytes	Machine
Instruction	Op Code	Bytes	Cycles
RET	83	1	2
RETR	93	1	2
RL A	E7	1	1
RLC A	F7	1	1
RR A	77	1	1
RRC A	67	1	1
SEL MBk	111k0101	1	1
SEL RBk	110k0101	1	1
STOP TCNT	65	1	1
STRT CNT	45	1	1
STRT T	55	1	1
SWAP A	47	1	1
XCH A,RN	00101nnn	1	1
XCH A,@R	0010000r	1	1
XCHD A,@R	0011000r	1	1
XRL A,RN	11011nnn	1	1
XRL A,@R	1101000r	1	1
XRL A,#DATA	D3 MM	2	2

bbb - Three bits designating which bit of the Accumulator is to be tested.
ee - Two bits designating an 8243 expander port.
- 00 - P4
- 01 - P5
- 10 - P6
- 11 - P7
k - One bit selecting a memory or register bank.
- 0 - MB0 or RB0
- 1 - MB1 or RB1
MM - Eight bits of immediate data.
nnn - Three bits designating one of the eight general purpose registers.
pp - Two bits designating one of the on chip I/O ports.
- 00 - BUS
- 01 - P1
- 10 - P2
qq - Two bits designating either I/O port 1 or I/O port 2.
- 01 - P1
- 10 - P2
r - One bit selecting a pointer register.
- 0 - R0
- 1 - R1
xxx - The high order three bits of a program memory address.
XX - The low order eight bits of a program memory address.

last modified 11JUN04

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