MicrosoftHyperTerminal is a small program that comes with Microsoft Windows.You can use it to send AT commands to your mobile phone or GSM/GPRSmodem. It can be found at Start -> Programs ->Accessories -> Communications -> HyperTerminal.If you cannot find it and you are using Windows 98, then probably youhave not installed it. You can go to Control Panel ->Add/Remove Programs -> Windows Setup tab ->Communications list box item -> Details button toinstall MS HyperTerminal.
Beforeyou start programming your SMS application, you may want to check ifyour mobile phone, GSM/GPRS modem and SIM card are working properlyfirst. The MS HyperTerminal is a handy tool when it comes to testingyour GSM devices. It is a good idea to test your GSM devicesbeforehand. When a problem occurs, sometimes it is difficult to tellwhat causes the problem. The cause can be your program, the GSMdevice or the SIM card. If you test your GSM device and SIM card withMS HyperTerminal and they operate properly, then it is very likelythat the problem is caused by your program.
Connectyour mobile phone or GSM/GPRS modem to a computer and set up thecorresponding wireless modem driver. You should find the wirelessmodem driver in the CD or disk that was provided by themanufacturer. If the manufacturer does not provide such CD or diskwith your mobile phone or GSM/GPRS modem, you can go to themanufacturer's web site and see whether the wireless modem drivercan be downloaded there. If the wireless modem driver cannot befound on the web site, you can still use Windows' standard modemdriver.
Inthe Connect To dialog box, choose the COM port that yourmobile phone or GSM/GPRS modem is connecting to in the Connectusing combo box. For example, choose COM1 if your mobile phoneor GSM/GPRS modem is connecting to the COM1 port. Then click the OKbutton.(Sometimes there will have more than one COM port inthe Connect using combo box. To know which COM port is usedby your mobile phone or GSM/GPRS modem, follow the procedurebelow:In Windows 98:Go to Control Panel ->Modem. Then click the Diagnostics tab. In the listbox, you can see which COM port the mobile phone or GSM/GPRS modemis connected to.In Windows 2000 and Windows XP:Go toControl Panel -> Phone and Modem Options. Thenclick the Modems tab. In the list box, you can see which COMport the mobile phone or GSM/GPRS modem is connected to.)
TheProperties dialog box comes out. Enter the correct portsettings for your mobile phone or GSM/GPRS modem. Then click the OKbutton.(To find the correct port settings that should beused with your mobile phone or GSM/GPRS modem, one way is to consultthe manual of your mobile phone or GSM/GPRS modem. Another way is tocheck the port settings used by the wireless modem driver that youinstalled earlier.To check the port settings used by thewireless modem driver on Windows 98, follow these steps:a. Go toControl Panel ->Modem.b. Selectyour mobile phone or GSM/GPRS modem in the list box.c. Click theProperties button.d.The Properties dialogbox appears. The Maximum speedsfield on the Generaltab corresponds to HyperTerminal's Bits per secondfield. Click the Connectiontab and you can find the settings for data bits, parity and stopbits. Click the Advancedbutton and you can find the setting for flow control.Tocheck the port settings used by the wireless modem driver on Windows2000 and Windows XP, follow these steps:a. Go to ControlPanel -> Phone andModem Options -> Modemstab.b. Select your mobile phone or GSM/GPRS modem in the listbox.c. Click the Propertiesbutton.d. The Propertiesdialog box appears. Click the Advancedtab and then click the Change Default Preferencesbutton.e. The Change Default Preferencesdialog box appears. The Port speedfield on the Generaltab corresponds to HyperTerminal's Bits per secondfield. You can also find the setting for flow control on the Generaltab. On the Advancedtab, you can find the settings for data bits, parity and stop bits.)
Type"AT" in the main window. A response "OK" shouldbe returned from the mobile phone or GSM/GPRS modem.Type"AT+CPIN?" in the main window. The AT command "AT+CPIN?"is used to query whether the mobile phone or GSM/GPRS modem iswaiting for a PIN (personal identification number, i.e. password).If the response is "+CPIN: READY", it means the SIM carddoes not require a PIN and it is ready for use. If your SIM cardrequires a PIN, you need to set the PIN with the AT command"AT+CPIN=".
The Robustel Industrial Cellular Modem M1000 MP is a compact design cellular modem based on GSM/GPRS/EDGE/UMTS/ HSDPA/HSUPA/HSPA+ networks. It offers the state-of-the-art 2G/3G connectivity for machine to machine (M2M) applications, providing users with reliable data transmission.
I've been working on an application which uses a GSM modem for one of two things; check its status using the built in HTTP stack by sending a GET request to the server, or sending data to the server (using UDP). I have tried several different methods to keep this as reliable as possible, and I'm finally ready to ask for help.
So the problem is sometimes the modem is busy doing something, and misses a command. As a human, I would see that and just resend the command. Adding a facility for my MCU to timeout and resend isn't an issue.
What is an issue is that the modem sends unsolicited responses after different events. When the modem changes registration status (with the cell tower) it would respond with +CGREG: 1, ... or when the GPS is ready GPS Ready. These responses can happen at any time, including in the middle of a command (like creating an IP connection).
This is a problem, because I haven't thought of a way to deal with this. My application needs to send a command (to connect to the server for example, AT+CIPSTART="UDP","example.com",5000) This command will response with 'OK', and then when the command has finished 'CONNECT OK'. However, I need to be able to react to the many other possible responses, and I haven't figured out a way of doing this. What do I need to do with my code to; wait for a response from the modem, check the response, perform an action based on that response?
A GSM modem is a specialized type of modem which accepts a SIM card, and operates over a subscription to a mobile operator, just like a mobile phone. From the mobile operator perspective, a GSM modem looks just like a mobile phone.
For the purpose of this document, the term GSM modem is used as a generic term to refer to any modem that supports one or more of the protocols in the GSM evolutionary family, including the 2.5G technologies GPRS and EDGE, as well as the 3G technologies WCDMA, UMTS, HSDPA and HSUPA.
GSM modems can be a quick and efficient way to get started with SMS, because a special subscription to an SMS service provider is not required. In most parts of the world, GSM modems are a cost effective solution for receiving SMS messages, because the sender is paying for the message delivery.
A GSM modem can be a dedicated modem device with a serial, USB or Bluetooth connection, such as the Falcom Samba 75 used in this document. (Other manufacturers of dedicated GSM modem devices include Wavecom, Multitech and iTegno.) To begin, insert a GSM SIM card into the modem and connect it to an available USB port on your computer.
Due to some compatibility issues that can exist with mobile phones, using a dedicated GSM modem is usually preferable to a GSM mobile phone. This is more of an issue with MMS messaging, where if you wish to be able to receive inbound MMS messages with the gateway, the modem interface on most GSM phones will only allow you to send MMS messages. This is because the mobile phone automatically processes received MMS message notifications without forwarding them via the modem interface.
It should also be noted that not all phones support the modem interface for sending and receiving SMS messages. In particular, most smart phones, including Blackberries, iPhone, and Windows Mobile devices, do not support this GSM modem interface for sending and receiving SMS messages at all at all. Additionally, Nokia phones that use the S60 (Series 60) interface, which is Symbian based, only support sending SMS messages via the modem interface, and do not support receiving SMS via the modem interface.
NowSMS will verify that it can communicate with the modem, and that the modem supports several of the basic AT commands defined in the ETSI GSM 07.05 (3GPP TS 23.005) specification. If the modem is successfully tested, NowSMS will display the following:
When you encounter any error initialising a GSM modem, we recommend the following troubleshooting steps outlined below. These general troubleshooting steps will be followed by suggestions that are specific to particular error conditions.
Unable to access modem, ensure that it is powered on and passes diagnostic tests: This error message is displayed when there is a communications error communicating with the modem. Another error message should have been displayed prior to this message, and that error message contains more specific information about the nature of the problem.
SIM900A GSM GPRS USB Modem for SMS and Data designed and manufactured by Graylogix for industrial applications related to GSM, which works on standard AT commands with 9600 Baud rate. Best suitable for SMS and Data applications, supports all types of sim cards except JIO, This modem works on 2G network and has one external antenna and it is USB self powered. Fast and stable network performance.
This text gives detailed information on the installation of the GSM Modem driver. The GSM modem driver can be used to send and receive SMS messages with a GSM phone attached to the PC. The installation of this driver can be started from the server manager by clicking on the Installed drivers menu item fromthe Drivers menu. In the "Available drivers for installation" window the GSM Modem install link should be clicked and the installation processwill start. After then installation process has finished, you'll see the GSM Modem 1 appearing in the list of drivers in the "Currentlyinstalled drivers" screen. On this page you can start the configuration by clicking on the Configure link (Figure 1). 2b1af7f3a8