RECEIVE UNREADABLE RESPONSE FROM GSM INTERFACE WITH 89C51

I receive unreadable response from gsm interface with 89c51 mcu,
My code is below

ORG 0000H
MOV A,#0EH
ACALL COMMAND
ACALL STATUS
MOV A,#38H
ACALL COMMAND
ACALL STATUS
MOV A,#06H
ACALL COMMAND
ACALL STATUS
ACALL CLEAR
MOV TMOD,#20H
MOV TH1,#-3
MOV SCON,#50H
SETB TR1
MOV DPTR,#TABLE
MOV R0,#2
H_1: CLR A
MOVC A,@A+DPTR
JZ B_1
ACALL SEND
INC DPTR
SJMP H_1
SEND: MOV SBUF,A
H_2: JNB TI,H_2
CLR TI
RET
B_1: JNB RI,B_1
MOV A,SBUF
MOV P0,A
ACALL DISPLAY
CLR RI
SJMP B_1
DISPLAY: SETB P2.0
CLR P2.1
SETB P2.2
ACALL DELAY
CLR P2.2
RET
COMMAND: MOV P0,A
CLR P2.0
CLR P2.1
SETB P2.2
ACALL DELAY
CLR P2.2
RET
DELAY: MOV R6,#255
DEL: MOV R7,#255
DEL1: DJNZ R7,DEL1
DJNZ R6,DEL
RET
STATUS: CLR P2.0
CLR P2.2
SETB P2.1
MOV P0,#0FFH
SETB P2.2
MOV A,P0
JB ACC.7,STATUS
CLR P2.1
CLR P2.2
RET
CLEAR: MOV A,#01H
ACALL COMMAND
RET
TABLE: DB 'AT',0DH,0
END

What do you mean by unreadable response? And can you put some light on what this code do?

DINESH40,


MOV TMOD,#20H
MOV TH1,#-3 -> MOV TH1,#3
MOV SCON,#50H
SETB TR1
MOV DPTR,#TABLE

@viniciusheidrun, code is fine. It should be -3 which is similar to 0 - 3 = 253 (8 bit unsigned subtraction) = 0xFD