How do I add a phone number to the SIM900? Can I add a phone number to the SIM900? Assuming I can, would I send the phone number through the AT Commands or the actual SIM card? I don't know how to write to a SIM card without another phone, so I am lost on how to write it standalone. The purpose of this is that I want to add my phone number to another device that uses Arduino and an SIM900 breakout. It is a project that could use that "phone" to receive calls and SMS and etc.
You don't write a phone number to the SIM900.
Your cellular service provider writes the phone number, along with other account information, to a SIM card. You connect the SIM card to the device.
You will need a separate phone number for the SIM900 - unless you want to pull the sim card out of your phone every time you want to use it.
Even if you could program a new SIM card to have exactly the same information as the one in your phone, your provider would detect that and be very unhappy with you.