Need Help with interfacing keypad with 8051 using rf module

[mert]

Hey people,
I am a newbie here:)
I have a project with 8051 as I write at the title.Actually my project is very similar to http://www.engineersgarage.com/microcontroller/8051projects/interface-keypad-AT89C51-circuit this one.The differance is I will use a rf module to make it wireless.
I wrote the codes with assembly and there is no problem with it.I simulated it with both proteus and multisim.But I don’t know how to use preamble and syncron data for rf module coding with assembly.
Here is the circuit diagram without rf module.I made it to simulate if my codes are right.I will add rf then.

 

 

 

 

Here is the assembly codes for receiver mcu:

ORG 0

MOV DPTR,#TABLO

BASA:

MOV P1,#0FFH

ANL P1,#0FH

MOV A,P1

CALL D?SPLAY

SJMP BASA 

D?SPLAY:

MOVC A,@A+DPTR

MOV P3,A

 

TABLO:

DB 3FH

DB 06H

DB 5BH

DB 4FH

DB 66H

DB 6DH

DB 7DH

DB 07H

DB 7FH

DB 6FH

db 77h

db 7ch

db 39h

db 5eh

db 79h

db 71h

ljmp BASA

END

This is the transmitter mcu :

ORG 00H

MOV DPTR,#LUT

MOV P1,#0FFH

MOV P3,#00H

 

BACK:MOV P1,#11111111B

     CLR P1.0

NEXT1:JB P1.4,NEXT2

      MOV A,#1H

      ACALL DISPLAY

NEXT2:JB P1.5,NEXT3

      MOV A,#2H

      ACALL DISPLAY

NEXT3:JB P1.6,NEXT4

      MOV A,#3H

      ACALL DISPLAY

NEXT4:SETB P1.0

      CLR P1.1

      JB P1.4,NEXT5

      MOV A,#4H

      ACALL DISPLAY

NEXT5:JB P1.5,NEXT6

      MOV A,#5H

      ACALL DISPLAY

NEXT6:JB P1.6,NEXT7

      MOV A,#6H

      ACALL DISPLAY

NEXT7:SETB P1.1

      CLR P1.2

      JB P1.4,NEXT8

      MOV A,#7H

      ACALL DISPLAY

NEXT8:JB P1.5,NEXT9

      MOV A,#8H

      ACALL DISPLAY

NEXT9:JB P1.6,NEXT10

       MOV A,#9H

       ACALL DISPLAY

NEXT10:SETB P1.2

       CLR P1.3

       JB P1.5,BACK

       MOV A,#0H

       ACALL DISPLAY

 

       LJMP BACK

 

DISPLAY:

        MOVC A,@A+DPTR

        MOV P3,A

        RET

 

LUT: DB 00000000b

     DB 00010000b

     DB 00100000b

     DB 00110000b

     DB 01000000b

     DB 01010000b

     DB 01100000b

     DB 01110000b

     DB 10000000b

     DB 10010000b

     END

.

 

And now I need your help.this is my first rf project so I don’t know where and how to add preamble and syncron data.Can you pls help me.For further information you can contact me from [email protected] or here.

 

[AJISH ALFRED]

Hi mert,

There are RF modules which transmit data using their own Preample and Sync bits, you dont have to code for it.

Which RF module are you using?

[Ashutosh Bhatt]

do u want to transmit keypad codes to another micro controller?

why u want to do that?

you need RF encoder-decoder chips like HT12E-HT12D along with RF Tx and Rx modules for this operation

[mert]

Hey people,
Thank you for your replies.
I will do this for a project of my microchips lecture.And to learn how rf modules work.
I have a basic 433mhz  rf module already.But i don’t know its model. My rf module doesnt have its preamble codes.So I have to write these codes.
And yes I have HT12E/D for my circuit.The photo I sent was only for showing what I am trying to do.In addition to this photo i have rf module and HT12 E/D in my circuit.I didnt try it yet because I dont have a 8051 programmer.On monday i will try it at the school.
 

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