[SOLVED] sim300 interfacing with 8051

[debabrta kar]

hi evry1 plz help me m sending at +cnmi command to the modem sim300 but not getting a new sms indiaction ...whenever a new msg is coming to the sim modem is not giving any indication...plz help me whats the problem....?

SMS / SHORT HAND TYPING IS NOT ALLOWED HERE
NEXT TIME YOU WILL GET A WARNING..
READ RULES BEFORE POSTING : MOD

 

[aameer]

are you testing with PC or micro controller.

 

[debabrta kar]

sir m testing with microocntroller at89s51

 

[aameer]

did you got OK when you transmitted AT
first send AT enter
check for OK
later send AT+CMGF=1 enter
check for OK
then wait untill You recieve +CMTI:"SM",1// 1 if you have no messages in your inbox

 

[debabrta kar]

yes sir m getting a response as OK after comannd AT, AT+CMGF=1 AND AT +CNMI=2,1,0,0,0 but then when a new message is comming then indication must be +CMTI:"SM" 1...so in recieving part if i am comapring with any of the character of +CMTI:"SM",1..but its not giving a match...so m not able to go furthr to send the command AT+CMGR=1.. so plz gide me how to proceed.....thanx in advance..

 

[aameer]

After AT+CMGF=1
delete the first message with command AT+CMGD=1 enter
then send a new message
Then the incoming message will be stored in first location of the inbox
Now message is coming but it is stored in different location as the inbox is not empty.
For example if you have already 3 messages in inbox the new incoming message will be stored in 4th location.so sim300 will give +CMTI:"SM" 4.
So delete the 1 first message then check as told before.

 

[debabrta kar]

yessir m doing the same ...also i used to delete the message at 1st position through hypoterminal also..but didnot get any new msg indication.........

 

[aameer]

check whether the network status.
Dial the sim placed in gsm module and watch it on hyper terminal.
whether it is giving any feedback.
check the antenna ,whether you have connected.
first test it in hyerterminal.
AT+CMGR=1 or any message

 

[debabrta kar]

sir with your guidance i had proceed further an now i am getng the indication as OK+CMTI:"SM", but the index number is not coming i mean i comapred with 0AH but same result i found....may i knw what is last character of the new mssg indication so that i can comapre with that and can proceed further

 

[aameer]

the last character will be the messages you have in your inbox. if it already contains 5 messages in inbox then new incoming message will be stored in 6th location..again new message means in 7th location. so better you delet the 1st message and read for 1st message

Follow these steps once.

AT <enter>
OK
AT+CMGF=1 <enter>
OK
AT+CMGD=1 <enter>
OK
AT+CMGR=1 <enter>
OK
then send new message
you will get +CMTI: "SM",1
then AT+CMGR=1 <enter>
the send message will be displayed...

 

[debabrta kar]

sir actually last character is 0AH i got it from sim300 document and my new msg indication is conformed bit it was not possible without u r concerned help....

 

[aameer]

i dint get what you told
did u got the result or still in problem

 

[debabrta kar]

yes i got the result

 

[aameer]

k. All the best.. carry on