Here’s a simple USB interface to communicate with a SIM900 modem by Jesus Echavarria. He wrote a post on his blog detailing its assembly:
Hi all! Here’s the new project where I’m working a couple of days. Since I develop the SIM900 module and test it, I don’t work with it. Also, I’ve got at home some samples of the MCP2200 USB bridge that I want to test it. So make an USB interface for this board was the perfect idea! This allows to use the SIM900 board with a PC, Raspberry or similar, with the plus of no need external power supply or control signals. Just plug the USB cable on the board and start communicating with the world!
Project details at Jesus Echavarria’s blog.
Via the contact form.