Embedded module manufacturing is incomplete without a proper test utility. We offer a nice, user interface for testing any type of GSM Modem which can be interfaced using UART Serial protocol with a system running Windows OS.
Power supply requirement:
For RS232 type modem mentioned in this link, requires adapter/battery of 12 Volt 1-2 Ampere current rating for reliable operation. DC Jack can be used to feed the input power.
For TTL Modem mentioned in this link, use 5 Volt, 1-2 Ampere adapter or Power bank.
The utility was actually developed for testing the SIM900A GSM modules manufactured by Elementz Engineers Guild Pvt Ltd. With the increase in demand and for quick testing we are providing the tool as a free software. The tool can be downloaded from our GitHub repository or from here.
This post describes the test method for SIM900A Modems, but virtually can test any Modem which supports UART protocol.
As shown in the above figure, user has to Scan for COM port using “Scan ports” button, select the COM port from the Port List. Choose the correct BaudRate(Default baudrate of Elementz SIM900A module is 9600). Click Open port and check the dialog box whether the COM port is opened. If opened sucessfully “Port opened successfully” should appear in the dialog box as shown below.
For making a call, just type the Phone number inside the box and Press Call. For disconnecting the call press End Call.
Similarly for sending SMS to a particular number, fill the Phone number Box and type your message in Message box and click Send.
For Modems other than SIM900, there is a provision for testing the modem using AT Command dialog box.
For example: for reading SMS from memory location 1 type
AT+CMGR=1 and press Enter
The message will be displayed in the Message Box.
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Hello Sir,
actually i use above tester software it can work on AT commands properly but when my SMS service application is run for reading sms on every 5 second it can read up to some hours . then it goes deadlock because AT commands has not responds like “OK” or “Error” .
then i close my application and open tester (above software test utility that you provide)
but there is also not work AT command . only connection is establish with port.
also i am change the baud rate for testing on AT commands but it not Respond to me.
Either is Adapter problem or modem configuration problem.
Please Kindly Help me …
It seems to be network related. Try resetting your modem by at command when not responding.
If using 12 Volt or more, proper heatsink should be placed on LM317, if you are applying power for more than 5 hours. Also try to increase the polling time interval to ensure it is not a firmware issue.
I was looking at this product http://elementzonline.com/sim900a-gsm-modem-module-with-sma-antenna-rs232-ttl-i2c-output–74?search=sim900
There is no specification for power supply. Although you have written a blog on how to use this gsm module with arduino, but regarding the connection, you just mentioned about the Tx and Rx pins. Can you please write in more detail about the power connections, preferrably with diagrams?
I am in serious doubt to see that most of the sites on the web are consciously avoiding to describe the power supply connections. Is this a AC powered module or DC? How much min/max current and voltage and through which pins, jacks – please elaborate.
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Hello!
I have tried your instructions but after i open port it shows “cannot open port for interfacing gsm modem.
Can you please explain the problem and solution also.
Thank you!
Check if the same port is opened in another application. If so close the other application and try again. Appreciate your valuable feedback.