weird response from sim900

             ORG 0H
             ACALL INT_LCD
             MOV TMOD,#20H
             MOV TH1,#-3
             MOV SCON,#50H
             SETB TR1
             CLR RI
A_1:		 JNB RI,A_1
H_1:		 MOV DPTR,#MYDATA
D_1:         CLR A
             MOVC A,@A+DPTR
			 ACALL DATAWRT
			 ACALL DELAY
			 INC DPTR
			 JZ C_2 
			 SJMP D_1 
C_2:		 ACALL CLR_LCD
H_2:         MOV DPTR,#MSG_1
D_2:         CLR A
			 MOVC A,@A+DPTR
			 JZ B_2
			 ACALL SEND
			 INC DPTR
			 SJMP D_2
B_2:         ACALL RECV
			 ACALL DATAWRT
			 ACALL DELAY
			 ACALL CLR_LCD
			 ACALL INT_LCD
H_3:         MOV DPTR,#MSG_2
D_3:         CLR A
			 MOVC A,@A+DPTR
			 JZ B_3
			 ACALL SEND
			 INC DPTR
			 SJMP D_3
B_3:         ACALL RECV
			 ACALL DATAWRT
			 ACALL DELAY
			 ACALL CLR_LCD
			 ACALL INT_LCD
H_4:         MOV DPTR,#MSG_3
D_4:         CLR A
             MOVC A,@A+DPTR
             JZ B_4
             ACALL SEND
			 INC DPTR
			 SJMP D_4
B_4:         ACALL RECV
			 ACALL DATAWRT
			 ACALL DELAY
			 ACALL CLR_LCD
			 ACALL INT_LCD
H_5:		 MOV DPTR,#MYDATA
D_5:         CLR A
             MOVC A,@A+DPTR
			 ACALL DATAWRT
			 ACALL DELAY
			 INC DPTR
			 JZ AGAIN 
			 SJMP D_5
AGAIN:	     ACALL DELAY 
			 ACALL CLR_LCD
INT_LCD:     MOV A,#38H
             ACALL COMNWRT
		     ACALL DELAY
		     MOV A,#0EH
		     ACALL COMNWRT
		     ACALL DELAY
		     MOV A,#06H
		     ACALL COMNWRT
		     ACALL DELAY
		     RET
COMNWRT:     MOV P1,A
             CLR P0.0
		     SETB P0.1
		     ACALL DELAY
		     CLR P0.1
		     RET
DATAWRT:     MOV P1,A
             SETB P0.0
		     SETB P0.1
		     ACALL DELAY
		     CLR P0.1
		     RET
DELAY:       MOV R0,#2
HERE3:       MOV R3,#250
HERE2:       MOV R4,#255
HERE:        DJNZ R4,HERE
             DJNZ R3,HERE2
			 DJNZ R0,HERE3
		     RET
SEND:        MOV SBUF,A
PUT:         JNB TI,PUT
             CLR TI
			 RET
RECV:        JNB RI,RECV
             MOV A,SBUF
			 CLR RI
			 RET
CLR_LCD:     MOV A,#01H
             ACALL COMNWRT
			 ACALL DELAY
			 RET

ORG 300H
MYDATA: DB " HELLO ",0
MSG_1: DB "A",0
MSG_2: DB "AT",0
MSG_3: DB "AT+CMGF=1",0
END