INTERFACING OF 89C51 WITH GSM

[mahesh]

I want to send a string through SIM 300 GSM Module .. what are the steps i have to follow ??

[doraemon]

u mean u want to send string to server or to send AT commands.

[mahesh]

Yeah i want to send string thro GSM Module using AT commands without PC

[Ganesh Selvaraj]

There are many tutorials regarding interfacing of gsm modem with a microcontroller in this website. GO TO EG LABS and choose the controller.

[SHAH DISHANT H.]

Hi,

 

Interfacinf GSM is as easy as sending data on UART. Refer datasheet of SIM300 and find the sequence of data to be sent.

[mahesh]

I had tried something …

 

bt its nt working at all

 

any1 help me out to get off the errors ..

 

the code is like :

 

ORG 0000H
SJMP MAIN
ORG 0040H

MAIN:
;ACALL DELAY_10

GSM :

MOV TMOD,#20H  ; timer 1 mode 2
MOV SCON,#50H;  serial mode 1, rec enable
MOV TH1,#0FDH
SETB TR1  ;start timer

MOV DPTR,#M2
MOV R6,#02H
A1 :
MOV A,#00H
MOVC A,@A+DPTR
ACALL SEND
INC DPTR
DJNZ R6, A1
MOV A,#13
ACALL SEND
ACALL DELAY_SMALL

MOV DPTR,#M1
MOV R7,#09H
A2 :
MOV A,#00H
MOVC A,@A+DPTR
ACALL SEND
INC DPTR
DJNZ R7, A2
MOV A,#13
ACALL SEND
ACALL DELAY_SMALL

MOV DPTR,#M3
MOV R5,#8
A3 :
MOV A,#00H
MOVC A,@A+DPTR
ACALL SEND
INC DPTR
DJNZ R5, A3
MOV A,#'”‘
ACALL SEND

MOV DPTR,#M4
MOV R4,#13
A0 :
MOV A,#00H
MOVC A,@A+DPTR
ACALL SEND
INC DPTR
DJNZ R4, A0

MOV A,#'”‘
ACALL SEND
MOV A,#13
ACALL SEND
ACALL DELAY_SMALL

MOV DPTR,#MSG
MOV R4,#22H ; SET COUNT AS PER MSG LENGTH
MOV R4,#34
A4 :
MOV A,#00H
MOVC A,@A+DPTR
ACALL SEND
INC DPTR
DJNZ R4, A4

MOV A,#1AH
ACALL SEND
ACALL DELAY_SMALL

ACALL DELAY_SMALL
;LJMP MAIN

SEND : MOV SBUF,A
WAIT : JNB TI, WAIT
CLR TI
RET

M1 : DB “AT+CMGF=1”
M2 : DB “AT”
M3 : DB “AT+CMGS=”
M4 : DB “XXXXXXXXXX”

MSG : DB “TOTAL DATA=1 & FINAL DATA=  1108000”

DELAY_SMALL :
MOV R1,#07H
D1 : MOV R2,#0FFH
D2 : MOV R3,#0FFH
D3 : DJNZ R3,D3
DJNZ R2,D2
DJNZ R1,D1
RET

;DELAY_10 :
 
;MOV P1,#00H ; LED FLASH @ PORT P1
;ACALL DELAY_SMALL ; LED FLASH @ PORT P1
;MOV P1,#0FFH ; LED FLASH @ PORT P1
;ACALL DELAY_SMALL ; LED FLASH @ PORT P1

;MOV R5,#10
;MIN_1 :
;MOV R4,#60
;MIN_10 :
;ACALL DELAY_SMALL
;DJNZ R4,MIN_1
;DJNZ R5,MIN_10
;RET

END

[Ganesh Selvaraj]

Why don’t you try Embedded C… it is easier and you get a lot code examples also online

[Author]

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