GSM SIM 300 interfacing

DO THE CONFIGRATION AS BELOW

SELECT 9600

PARITY NONE

BIT RATE 8

TYPE AT AND SEND

IF REPLY IS OK THEN MODEM IS CONNECTED

PRODUCT NAME     : GSM MODEM
HARDWARE      :  SIM 300 MODULE
COMMUNICATION     : RS232
COMMANDS    : AT
INPUT VOLTAGE    : 12VDC / 1AMP   
*************************************************************************************************************************
ANTENNA  -  PULL THE ANTENNA OUT IF THE SIGNAL IS WEAK

HOW TO TEST!!!!

1. INSERT THE SIMCARD INTO SIM TRAY BACKSIDE
2. CONNECT THE RS232 CABLE TO THE PC SERIAL PORT -  SERIAL PORT PROPERTIES ( RESTORE DEFAULTS - 9600 BAUD RATE)
3. OPEN HYPERTERMINAL FROM WINDOWS START>PROGRAMS>ACCESARIES>COMMUNICATIONS>HYPERTERMINAL
4. SELECT THE COMPORT WITH BAUD RATE 9600
5. TYPE "AT " ECHO "OK" IF ECHO IS OK COMMUNICATION IS OK !!!!!!!!!+


6. CHECK THE LED STATUS ( NETWORK SERCHING , NETWORK CONNECTED, IS SHOWN IN LED STATUS GIVEN BELOW)
****************************************************************************************************************************
 Working state of network status indication LED OUTPUT

State SIM300 function

Off SIM300 is not running
64ms On/ 0.8SEC Off SIM300 does not find the network
64ms On/ 3 SEC Off SIM300 find the network
64ms On/ 300ms Off GPRS communication
*****************************************************************************************************************************

TO CHQ GAIN - AT+CSQ=?
TO CHK NETWORK - AT+COPS=?


Examples for send and receive SMS

For sending SMS in text Mode:

AT+CMGF=1 press enter
AT+CMGS=”mobile number” press enter
Once The AT commands is given’ >’ prompt will be displayed on the screen.
Type the message to sent via SMS. After this, press ctrl+Z to send the SMS.
If the SMS sending is successful, “ok” will be displayed along with the message number.


For reading SMS in the text mode:
AT+CMGF=1 Press enter
AT+CMGR= no.
Number (no.) is the message index number stored in the sim card. For new SMS, URC will be received
on the screen as +CMTI: SM ‘no’. Use this number in the AT+CMGR number to read the message.
Voice call
Initiating outgoing call:
ATD+ mobile number; press enter
For disconnecting the active call:
ATH press enter
For receiving incoming call:
ATA press enter



**************************************************USEFUL AT COMMANDS FOR SETTINGS *****************************************************************

TO CHANGE BAUDRATE  - AT+IPR=BAUDRATE(Ex 9600) 0-115200 For maore details refer AT commands Document page 33

TO SAVE THE SETTINGS AT&W

TO RESTORE FACTORY DEFAULTS TYPE AT&F THEN SAVE IT AT&W

do the configration as below

Hi, 

We are also facing the same problems, We also have the SIMCOM 300. It is not able to generate the call through the Microcontroller.

Did you find the solution to it? Please help us with the issue, if you have got the solution.

Thank You for your Help.

I have faced same issue recently and fixed it by applying small work around in it. See...the module I purchased (plz check your module) is (ONLY) "RS232" interface with modem,  NO TTL compatibility.

The problem I faced was, the module supported to communicate via HyperTerminal, but no response when I tried with TTL logic (ie. via 89c51). Then I bye-passed the wires runing out from MAX232 (Note: to communiate in TTL logic, we do NOT require the help of MAX232, if you don't want you may remove from the board), to the pin 11 and 12 of MAX232 and connect with RX & TX of MC respectively. Now it is working....!

Thank you.

Muthu Kumar G.

Hi,

     Is it possible to send SMS to multiple numbers at a time through SIM 300?? I can able to send SMS to a single number.

Hi Srikanth,

It is not possible to send SMS to multiple numbers at a time. The only way to send SMS to multiple numbers is to provide some time delay in your code after each SMS is sent successfully.

You can't sent the messages to multiple numbers simultaneously, but ofcourse you can send messages to multiple numbers in a quick succession. Just add a delay between each message sent.

And you know, it dosen't matter since the delivery of the message depends on the network, and there will be surely a significant delay no matter how quick you send to multiple numbers.

Amrith 

            thanx for your replies..  If the network unable to delivery the message  in time , then no use of my project. it can b happend due to jamming in network.  So is it possible for my microcontroller to see the delivary report and send again??

Yes, it is possible. Once you've send a message, you should wait for the required delivery report string from the module. If it is a successful delivery, then send the next message

 Thanx Amrith for the reply and i will try it tomorrow.

              Can you pls tell me how the crystal frequency like 4Mhz or 20 Mhz  influences my delay which i gave in the program.

Because when iam executing ATDXXXXXX;  command, its nt getting successful sometimes but is working fine with Hyperterminal all the time and also iam started working on gprs for data transfer from remote to home pc, pls give me some guidance. thanx  ...

Hi Amrit,

     Can I have your mail Id ?

Hi  Srikanth,

my mail id is amrith.tins@gmail.com

Hi srikanth,

Crystal oscillator frequency & delay routine are much related to each other. If you are using 20Mhz you need less delay compared to 4Mhz crystal. Generally most of the compilers has in build delay functions, which calculate the delay timings as you give the crystal oscillator value you are using. Refer your controller data sheet & timing diagrams for detailed description.

hi guys in some areas cell network is not available but while by going 5kms from there.there will be again full signal so based on this i want to do a small antenna which recieves the frequency for having atleast one strip of network so first of all is it possible to do and cany any one guide me in this plzz..

can any one help me on interfacing of gps and gsm module with atmega128????

i hav sim 300 gsm module and GSSM3 series GPS

i need some help from u guyzz

m making ma final year on tracking

send the program 

Hey, i m also facing the same problem right now. can ny1 help me out of this.

thanks in advance.

hi 

i have nokia 3500c mobile

is this mobile support AT commands?

if yes,then how can i connect this mobile to microcontroller (8051)

plz help me

HI

 WHEN I GIVE AT+COPS=? TO MODULE I RETURNS ERROR SAYING

+CME ERROR 22

WHAT DOES IT MEAN?

I need source code for sending sms from AT89s52 to Gsm module...kind reply...