Problem with GSM SIM900 module

[Vishal]

Dear Friends,

 

I am designing GSM based switching circuit, as I am new to this topic so before going to interface GSM module with Microcontroller I am testing with Hyper Terminal. 

 

When I swithced ON the circuit it shows messages like ready with default setting, as below –

 

 

RDY

 

+CFUN: 1

 

+CPIN: READY

 

but this message is appearing frequently/ continuesly so I am not able to type and do other action with GSM module e.g. send messages.

 

I can test only “AT” command and it result “OK” means GSM modem an SIM card is working fine.

AATT

 

 

OK

 

Only issue is ready messages are appering again and agian. so when I type some commands like AT+CMGF=1 suddenly above ready messages are comes in between which leads to interrupt the commands. I think GSM module is restarting.

 

Some times  “Call Ready” also appears along with above ready messages.

 

RDY

 

+CFUN: 1

 

+CPIN: READY

 

Call Ready

 

Kindly help me out in this regards. I am in urgent need.

 

Thanks in advanced.

 

Regards,

Vishal

[Amrith]

The problem you are facing is confusing. If there is any reset switch on the module, try reseting it. Take care that, no wire is touching any of the gsm module pins.

If your problem is solved with any other solution please share, so that every one here will gain.

[Vishal]

Dear Friends,

 

Above RESTART issue has been resolved.

 

Actually it was power supply issue, due to insufficient input current GSM module was restarting. Initially I was using regulated supply by 7805 and Zener diode, but afterwords I replaced with variable supply by LM317 and its working fine now.

 

Regard’s

Vishal

[Amrith]

Hey Vishal, 

Appreciate!!!

Thank you for sharing.

[hazrat ali]

dear sir! 

             i have problem that how  to switch on and off  the sim900 module using send sms….i want to switch on and off the GSM MODULE  by using sms when i wanted …..my project is to get data from MCU(atmega16/32) when i wanted  and then switched it off or at on sleeping mood…..if anyone know about it ….plz plz reply  me….

                                                    thanks

[hazrat ali]

dear friend(vishal)!

                   you should wait for awhile ….until CALL READY  comes on hyperteminal ….then check out your commands…..also check your power supply either i give correct voltage and current to your module…

[umar farrok]

in your program itself you can do it use relay to trip on only the condition is satisfies other than that the relay trip the supply off for the gsm modem try it

[hazrat ali]

 i don’t want to use relly….

 i want to control it by sending cammands….is this possible? can i do it with help of  +CPOF,+CFUN

 cammand…reply me …thanks

[vatsal shah]

hello,

        i am getting msg of cpin ready and not ready..call ready msg is not getting on hyperterminal.what should i do?

[Krushnakant Salunkhe]

vishal , i m facing same problem what should i do? What is power requirement for sim 900a ? I m giving power to modem by 5v adapter 1A current. Is it sufficient?? Plz reply fast

[Chaitanya]

Hello Guys Need Ur Help .My Problem is Only AT Command is working 

AT

 

OK

AT+CPIN?

 

ERROR

 

This was the Problem Please Help(Need Fast Reply) THANKS IN ADVANCE

[S.Sriramkumar]

i have a gsm 900a module…the modem is working properly because while i call the mobile which is used in the modem…i could hear a ring back sound….while i try to call it throuh the arduino….the at commands are sending…but the modem doesn't make the call…

 

[rifat499]

the modem is operating properly as though I call the transportable whatever is us…

[Anonymous]

how to fix thier problem in gsm  only power led on but not status led and sim notification led is not on

[Hari Prasaath K]

Pooventhan..

1. Have you changed the sim card and tried..

2. Check with any problem in the antenna.

3. Check with any problem in the sim card holder..

[Author]

Posts