Hello All,
From what I could find, cell phones with internet access use a dynamic IP address. If so, how could I use one the sparkfun cell units to control hardware in the field.
In general, how would a TCP/IP packet find its way to the cellular unit from the internet. Do these units have a wake feature so they don’t have to poll for packets?
Sorry if the questions seem basic, I am new to networking and wireless (as in 0 experience).
Thanks,
Cale
The GSM Module is configured as either a Client or Server. When configured as a Server it will accept incoming requests and output a message to the uP indicating this. You’ll only be able to accept incoming requests if your service provider allow its - not likely unless you have a data plan for something like a Laptop Data card. Even in that case you’ll probably have to contact customer service to have them enbale incoming request - and may have to pay extra for it.
Thanks, this is good to know.
Are there any tricks around this? For instance, can you use a sim card with both phone and data and have the unit respond when it receives a call? I will be trying to talk to a weather data logger.
Calegatter:
Are there any tricks around this? For instance, can you use a sim card with both phone and data and have the unit respond when it receives a call? I will be trying to talk to a weather data logger.
The most common scenario is for your device to act as a client and make a connection to your server when a specific event occurs (i.e wind speed is over x MPH) or on a periodic basis (once an hour, once a day, etc.). If you only want it to report data when queried you could have it respond to a call from a specific telephone number, or send it an SMS message.
In any of these cases, your device would be a client and would make a request to a server with data for the server to save. You would then have to connect to the server using a web browser to see the data that your device sent. If you want to connect directly to your device via a web browser you’ll need to configure it as a server and have a plan that allows it to accept incoming request.
Do you know of any prepay services that would allow incoming connections?
Calegatter:
Do you know of any prepay services that would allow incoming connections?
What Country are you in?
USA, Utah
In the US you have 2 options for GSM service providers - AT&T and T-Mobile, although you may also be able to locate a “reseller” - this depends a lot on how many devices you are deploying. You may need to have a “laptop Connect” card to initially setup your account.
AT&T has a couple of “DataConnect” plans - you have to search their web site to see pricing dependent on your location (http://www.att.com).
T-mobile has 3 data-only plans starting at $29.99/mo (http://www.t-mobile.com/shop/plans/Cell … rnet_email)