The clock on the white board

Whiteboard Clock - a device that writes the current time marker on a white board. Every X (by default - 5) minutes, it deletes the previous time and writes new.

Creator Gadget describes its design and publish the source code for motor control.



Yellow and red parts in the design printed on 3D-printer ( source code 3D-models for OpenSCAD).





Apart from these, requires two motors to control the "hand" and another motor for lifting the structure to the desired height.

Device Control provides microcontroller PIC16F1454, which receives commands from the computer by radio at 433 MHz from another of the same microcontroller. USB bus power only goes. That is a gadget, in principle, can be mobile if provide it with independent power supply.





On the radio small pieces of text in ASCII. Under Linux, these transfers are initiated by commands like

  & quot; echo 12:34 & gt; / Dev / whiteboard & quot;  code>  pre>. This command will write on the blackboard while 

  12:34  code>  pre>. 



The author has developed their own simple protocol for transmitting data, where "1" signal corresponds to 0, 0 and 2 ms, 1 ms of silence, while "0" - 0, 1 and 0 signal ms, 2 ms of silence. Each message is sent repeatedly to the error correction. 



 



Font determined by the simple task of X and Y (код). They are processed by the program C ++, which converts the coordinates to move the marker. 



 



These self-made watches resemble the project  Plotclock  year ago on Arduino. By the way, for it was published even more detailed instructions for assembly. 



  



Source:  geektimes.ru/post/246102/