8051 Assembly Address Based 16 bit Multiplication with carry program

    ORG 0000H

                MOV DPTR, #0030H

                MOVX A, @DPTR

                MOV B, A

                MOV R7, A

    INC DPTR

    MOVX A, @DPTR

    MUL AB

    MOV DPTR, #0090H

    MOVX @DPTR, A

    MOV A, B           

                MOV R0, A

                MOV A, R7

                MOV B, A

                MOV DPTR, #0032H

                MOVX A, @DPTR

                MUL AB

                ADD A, R0

                MOV R6, A

                MOV A, B

                MOV R5, A

                INC DPTR

                MOVX A, @DPTR

                MOV R3, A

                MOV B, A

                MOV DPTR, #0031H

                MOVX A, @DPTR

                MUL AB

                ADD A, R6

                MOV DPTR, # 0091H

                MOVX @DPTR, A

                MOV A, B

                MOV R4, A

                MOV DPTR, #0032H

                MOVX A, @DPTR

                MOV B, A

                MOV A, R3

                MUL AB

                ADD A, R5

                ADD A, R4

                MOV DPTR, #0092H

    MOVX @DPTR, A

                MOV A, B

                INC DPTR

                MOVX @DPTR, A

                MOV PCON, #02H

8051 Assembly Address Based 16 bit Subtraction program with Carry

    ORG 0000H

    CLR C

    MOV R1, #00H

                MOV DPTR, #0030H

                MOVX A, @DPTR

                MOV R0, A

                INC DPTR

                MOVX A, @DPTR

                SUBB A, R0

                JNC OVER1

                INC R1

                CPL A

                ADD A, #01H

                MOV DPTR, #0090H

                MOVX @DPTR, A

                MOV A, R1

                MOV R7, A

OVER1:   MOV DPTR, #0090H

                MOVX @DPTR, A

                MOV A, R1

                MOV R7, A

                MOV DPTR, #0032H

                MOVX A, @DPTR

                MOV R2, A

                INC DPTR

                MOVX A, @DPTR

                MOV R3, A

                MOV A, R2

                ADD A, R7

                MOV R2, A

                MOV A, R3

                SUBB A, R2

                JNC OVER2

                INC R4

                CPL A

                MOV A, #01H

                MOV DPTR, #0091H

                MOVX @DPTR, A

                MOV A, R4

                INC DPTR

                MOVX @DPTR, A

OVER2:   MOV DPTR, #0091H

                MOVX @DPTR, A

                MOV A, R4

                INC DPTR

                MOVX @DPTR, A

                MOV PCON, #02H

8051 Assembly Address Based 16 bit Addition with carry program

    ORG 0000H

                MOV DPTR, #0030H

                MOVX A, @DPTR

                MOV R0, A

                INC DPTR

                MOVX A, @DPTR

                MOV R1, A

                INC DPTR

                MOVX A, @DPTR

                MOV R2, A

                INC DPTR

                MOVX R3, A

                MOV A, R1

                ADD A, R1

                ADD A, R0

                JNC OVER1

                INC R7

OVER1:   MOV DPTR,#0090H

                MOVX @DPTR, A

                MOV A, R7

                ADD A, R2

                ADD A, R3

                JNC OVER2

                INC R6

OVER2:   INC DPTR

                MOVX @DPTR, A

                MOV A, R6

                INC DPTR

                MOVX @DPTR, A

                MOV PCON, #02H

Software: x8051 Dos Assembler for 32 and 64 bit windows 7

Mediafire Link: http://www.mediafire.com/?k3eyidzn92wlyqh

Install Procedure:-

1. Unzip the x8051 for 7.

2. Install the DOSBox0.74-win32-installer.

3. Create a folder on C:\ , and rename it x8051.

4. Copy downloaded Link, x8051 Application File and paste it on C:\x8051.

5. Open DOSBox 0.74 from desktop.

6. Write dos commend 

          Z:\> mount d c:\x8051\ (Enter)

          Z:\>d: (Enter)

          D:\>x8051 (Enter)

7. Assemble your .asm file.

Software: x8051 Dos Assembler for 32 bit Xp & Vista

Mediafire Link: http://www.mediafire.com/?es5vhu8kijlzh4a

Book: Phlips Semiconductors 80C51 Family Architecture

Mediafire Link:-  http://www.mediafire.com/?s4mb651za9i9rac

Book: Understanding 8085 8086 Microprocessors and Peripheral ICs through Question And Answer

Mediafire Link: http://www.mediafire.com/?prwc7kvhcfuank5

8051 Assembly Boolean Algebra NAND operation program

ORG 0000H

MOV DPTR, #0030H

MOVX A, @DPTR

MOV R0, A

INC DPTR

MOVX A, @DPTR

ANL A, R0

CPL A

MOV DPTR, #0090H

MOVX @DPTR, A

MOV PCON, #02H

8051 Assembly Boolean Algebra NOR operation program

ORG 0000H

MOV DPTR, #0030H

MOVX A, @DPTR

MOV R0, A

INC DPTR

MOVX A, @DPTR

ORL A, R0

CPL A

MOV DPTR, #0090H

MOVX @DPTR, A

MOV PCON, #02H