[Work In Progress]
Hello everyone, i made a project a couple of months ago that could interests the community. This is a SIM900 module based Machine to Machine shield for MSP430G2 launchpad.
Background and context :
Approching the end of courses at university and seeing the internship on the verge to begin, we had an Industrial computing project. Mine was too develop the program for a intrusion alarm using :
- GPRS/GSM module by ElecFreaks http://www.elecfreaks.com/store/gprsgsm-moduleefcom-por-p-450.html (to admin : i searched forum's rules but I didn't found it, so i don't know if linking a commercial website is considered as advertisement) at 36€
- PIR sensor
- The choice between an Intel 8051 dev board home made by professors or MSP430, come on i've worked on the first one the whole three months developping a little BIOS, it doesn't feel more interesting for you to get new knowledges about other microcontrollers, especially when your MSP430 is sleeping in its box?
Finally, I didn't success to get my mind into it, i've got a really bad mark but I still wanted to finish it without buying the same module, by doing it by myself.
My internship in an university's electronic lab began. And do you know what ? They made the most basic phone i ever seen, using also the SIM900 ! I could get the hardware files and software(for an ARM Cortex).
And the mind of the lab regarding students was "You have a project? Come to do it !".So equipments was available for personnal use, and me complaining all the time that i don't have enough equipments to achieve a lot of projects that i would like to do : that was the best moment for achieve my first personnal project.
Specifications :
- The main goal of this module was the intrusion alarm, but i prefered it modular as possible
- Not too expensive
-
Prototype 1 :
I learned a lot of this prototype : over half of space is unused, and
Prototype 2 :
This prototype works, but not fully tested : I need a good alimention to supply 2 Amps bursts from the SIM900 during active communication.
As you can see i made some mistakes, like useless vias not connected to ground planes
Professional PCBs :
What's new? TX_DEBUG and RX_DEBUG PIN of the SIM900 got 2 separates male pins to allow firmware's updating.
An other type of SMA connector is choosed.
At this moment i didn't know the term "Machine to Machine", and discovered later that the GPRS communication service(for web application) can be used and not only sms i found it more appropriate for the topic.
I cannot solder one of this version because tools needed. But I'm thinking about sending one to a person for free to test it, and if working i'll probably send few more "free samples". If my work really interests you, you can send me a message to maybe test it or get it for free.
Futur improvements :
Schematic & Layouts :
Files :