Summary
This fun project receives text messages (sms) and prints them via the thermal printer. Additionally, the number of received messages is displayed on the front. (I was a bit optimistic using an 8 digit display 😀 )
Materials Needed
- an arduino nano board
- an rs232 thermal printer
- an sim800l gsm module
- an 7 segment modul MAX7219
- an MAX232 IC with passives
- punch of transistors to build voltage dividers
- different voltage regulators (9V, 5V, 3.8-4.2V) and 3D printer - of course :D
Instructions
Casing
The case consists of a single block in which all the electronics can be placed it. The thermal printer nicely covers the housing and holds the 7-segment display module in place.
Hardware
I’ve drawn a diagram for the wiring which can be found on GitHub:
https://github.com/meiniKi/smsbox/blob/master/wiring_diagram.png
Please consider the different voltage levels!! A 5 volts supply will blow up the sim800 module!
Software
The software is in progress and can be found on GitHub.
https://github.com/meiniKi/smsbox/blob/master/smsbox.ino