Here one can find complete instruction set of 8051 microcontroller

January 10, 2015

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Here one can find complete instruction set of 8051 microcontroller. Complete information regarding each instruction like operational explanation, addressing mode, no. of byte occupied, no. of cycles used etc is given. So just, go through it. It’s a ready reference.

The complete 8051 Instruction Set or all 8051 instructions are broadly classify in to four groups data moving, logical, arithmetic and branching.

Data moving / handling Instructions:

Mnemonics	Operational description	Addressing mode	No. of bytes occupied	No. of cycles used
Mov a,#num	Copy the immediate data num in to acc	immediate	2	1
Mov Rx,a	Copy the data from acc to Rx	register	1	1
Mov a,Rx	Copy the data from Rx to acc	register	1	1
Mov Rx,#num	Copy the immediate data num in to Rx	immediate	2	1
Mov a,add	Copy the data from direct address add to acc	direct	2	1
Mov add,a	Copy the data from acc to direct address add	direct	2	1
Mov add,#num	Copy the immediate data num in to direct address	direct	3	2
Mov add1,add2	Copy the data from add2 to add1	direct	3	2
Mov Rx,add	Copy the data from direct address add to Rx	direct	2	2
Mov add,Rx	Copy the data from Rx to direct address add	direct	2	2
Mov @Rp,a	Copy the data in acc to address in Rp	Indirect	1	1
Mov a,@Rp	Copy the data that is at address in Rp to acc	Indirect	1	1
Mov add,@Rp	Copy the data that is at address in Rp to add	Indirect	2	2
Mov @Rp,add	Copy the data in add to address in Rp	Indirect	2	2
Mov @Rp,#num	Copy the immediate byte num to the address in Rp	Indirect	2	1
Movx a,@Rp	Copy the content of external add in Rp to acc	Indirect	1	2
Movx a,@DPTR	Copy the content of external add in DPTR to acc	Indirect	1	2
Movx @Rp,a	Copy the content of acc to the external add in Rp	Indirect	1	2
Movx @DPTR,a	Copy the content of acc to the external add in DPTR	Indirect	1	2
Movc a,@a+DPTR	The address is formed by adding acc and DPTR and its content is copied to acc	indirect	1	2
Movc a, @a+PC	The address is formed by adding acc and PC and its content is copied to acc	indirect	1	2
Push add	Increment SP and copy the data from source add to internal RAM address contained in SP	Direct	2	2
Pop add	copy the data from internal RAM address contained in SP to destination add and decrement SP	direct	2	2
Xch a, Rx	Exchange the data between acc and Rx	Register	1	1
Xch a, add	Exchange the data between acc and given add	Direct	2	1
Xch a,@Rp	Exchange the data between acc and address in Rp	Indirect	1	1
Xchd a, @Rp	Exchange only lower nibble of acc and address in Rp	indirect	1	1