The sensor bridge board is a small piece of embedded hardware that allows the user to easily connect up to six analog sensors. The board will then read the data from the sensors and send this data via the serial port to a client application which then either records the data to files or serves it over a websocket to interested applications.
The firmware (/firmware) of the sensor board is Arduino based and the board layout files (/hardware) are created with CadSoft/Autodesk Eagle
The data from the sensors is sent over the serial port at a baud rate of 9600 bps.
The serial protocol in which the data is communicated is very straighforward:
it will always send six two-byte (16 bit) values (ordered from sensor one to
sensor six), separated by a carriage return (0x0D) and a line feed
(0x0A). So one single message will always be 14 bytes long and be ordered
like this:
Sensor 1 value | Sensor 2 value | Sensor 3 value | Sensor 4 value |
Sensor 5 value | Sensor 5 value | Carriage return | Line feed
The sensor readings will have a value from 0 to 1023 (10 bit), and will be
sent with the high byte first. If it is detected that there is no sensor
connected to the analog input, a value of FF:FF will be sent to notify the
disconnected state of the sensor.
This is the message that is sent when only the first sensor is connected that
has a sensor reading of 0 (00:00).
00:00:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:0D:0A
This is the message that is sent when only the first sensor is connected that
has a sensor reading of 1023 (03:FF).
03:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:0D:0A
The firmware (everything under /firmware) is licensed under the GPLv3, the Arduino core libraries and IDE are under their own respective licenses (GNU LGPL and GNU GPL). License text can be found under /firmware/license.txt
The board layout files (everything under /hardware) is under the Creative Commons Attribution-ShareAlike 3.0 Unported License. License text can be found under /hardware/license.txt