Smart Notice Board
What and Why
This is another hobby project. Any display solution with a VGA input can be used a the notice board. Users text the messages to be displayed, along with an access code to a predefined number. The system would them display the messgae on the display
The system is built around an AVR microcontroller and a GSM modem. The GSM modem has a SIM card provided by the netork provider and can receive text messages. The microcontroller controls the modem and reads the incomming messages through AT commands over a serial port. The user has to send the text message prepended with the security access code. This prevents unauthorized people from spamming the system,
Once the text to be displayed is received and authenticated. The AVR microcontroller sends it over to the display as a VGA signal. Even though the tiny AVR controller does not have a VGA port, VGA signals are generated by bitbanging through the SPI port.
Here is a video of the system in operation.