AT89C51 based wireless RF Transmitter and Receiver

[karangp]

Hi

im using AT89C51 microcontroller for transmitter and receiver side.
wireless module is TWS 432A (Tx), RWS 432A(Rx)

I use serial communication to transmitt simple 8-bit data over wirless tranmitter TWS-432A. and the same i receive data to another microcontroller using Receiver RWS - 432 module, i can send more than three or four data to transmitter side. but i cann't receive the same data at receiver side.

in my project is sending 8-bit data from one Mc to another Mc over wirless medium, then received data should be viewed in system hyperterminal via serial port at the receiver side. i can't get exact 8-bit data, some datas are losing:?:.

for your ref : here with i attach my program listing for TX and Rx
Transmitter Program

org 000h

MOV TMOD,#20H ;timer 1, mode 2
MOV TH1,#-6 ;4800 baud
MOV SCON,#50H ;8-bit, 1 stop bit, REN enabled
SETB TR1 ;start timer 1

AGAIN: MOV A,#"A" ;transfer " "serial data transfer subroutine
ACALL SEND
MOV A,#"B"
ACALL SEND
MOV A,#"C"
SJMP AGAIN

SEND: MOV SBUF,A ;load SBUF
HERE: JNB TI,HERE ;wait for last bit to transfer
CLR TI ;get ready for next byte
RET


end

Receiver program

org 00h
MOV TMOD,#20H ;timer1, mode 2 (auto reload)
MOV TH1,#-6 ;4800 baud
MOV SCON,#50H ;8-bit, 1 stop, REN enabled
SETB TR1 ;start timer 1


THIS IS USED TO RECEIVE DATA SERIALLY VIA WIRELESS

HERE: JNB RI,HERE ;wait for char to come in
MOV A,SBUF ;save incoming byte in A
MOV P1,A
ACALL TRANS
CLR RI ;get ready to receive next byte
SJMP HERE


THIS ROUTINE IS USED TO SEND, RECEIVED DATAS TO SYSTEM'S HYPERTERMINAL

TRANS: MOV SBUF,A ;load SBUF
HERE1: JNB TI,HERE1 ;wait for last bit to transfer
CLR TI ;get ready for next byte
RET

end

please can u give suitable solution for that project.

my email id: xxxxxxxxxx@gmail.com[/color][/u]
MOD: Please note that we dont entertain private sharing. You need to reda rules/ announcements again.

 

[IanP]

It looks like you have to "slow down" your transmitting mcu. Look what is happening: transmitter sends byte after byte and you expect the receiver to receive one byte and re-transmit it, while in the same time next byte from the transmitter is on its way ..
After CLR TI insert 1ms time loop in the transmitter's SEND subroutine ..
Regards,
IanP

 

[karangp]

thaks for your suggestion, i will try it now. i will keep in touch with you.

 

[Maverickmax]

Out of curiosity, what kind of antenna did you use?

Maverick Max

 

[hm_fa_da]

hi

does your transceiver support 4800 bps ?
start from low speeds first ,
and only on one way transmitting first ,
then go to full duplex and 4800 baud .

and set TI at first of the program , means MOV SCON,#52H except MOV SCON,#50H

regards,