The Procedure for Sending AT Commands to a Mobile Phone or GSM/GPRS Modem Using MS HyperTerminal(Contd...)

6. The Properties dialog box comes out. Enter the correct port settings for your mobile phone or GSM/GPRS modem. Then click the OK button.
   
   
   
   
   (To find the correct port settings that should be used with your mobile phone or GSM/GPRS modem, one way is to consult the manual of your mobile phone or GSM/GPRS modem. Another way is to check the port settings used by the wireless modem driver that you installed earlier.
   
   
   
   
   To check the port settings used by the wireless modem driver on Windows 98, follow these steps:
   
   a. Go to Control Panel -> Modem.
   b. Select your mobile phone or GSM/GPRS modem in the list box.
   c. Click the Properties button.
   d. The Properties dialog box appears. The Maximum speeds field on the General tab corresponds to HyperTerminal's Bits per second field. Click the Connection tab and you can find the settings for data bits, parity and stop bits. Click the Advanced button and you can find the setting for flow control.
   
   To check the port settings used by the wireless modem driver on Windows 2000 and Windows XP, follow these steps:
   a. Go to Control Panel -> Phone and Modem Options -> Modems tab.
   b. Select your mobile phone or GSM/GPRS modem in the list box.
   c. Click the Properties button.
   d. The Properties dialog box appears. Click the Advanced tab and then click the Change Default Preferences button.
   e. The Change Default Preferences dialog box appears. The Port speed field on the General tab corresponds to HyperTerminal's Bits per second field. You can also find the setting for flow control on the General tab. On the Advanced tab, you can find the settings for data bits, parity and stop bits.)
   

7. Type "AT" in the main window. A response "OK" should be 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 is waiting for a PIN (personal identification number, i.e. password). If the response is "+CPIN: READY", it means the SIM card does not require a PIN and it is ready for use. If your SIM card requires a PIN, you need to set the PIN with the AT command "AT+CPIN=".
   
   
    

   If you get the responses above, your mobile phone or GSM/GPRS modem is working properly. You can start typing your own AT commands to control the mobile phone or GSM/GPRS modem.Further details about how to use AT commands to send and receive SMS messages will be provided in the following sections.