Activities
Our new group project is the restoration (and hacking) of some electromagnetic flip-dot bus display panels. New display cases will have to be fabricated, and control boards for each display. A software interface is also needed for control the panels over a network etc. Suggestions and contributions are welcome, see the mailing list!
Tom has reverse engineered a schematic for the panel. Combining this with logic analysis Peter performed at the uni has allowed us to discover how we can control the state of each pixel on the panel. Our current setup involves using a breadboard with a few tac switches on it to manually pull some of the address lines high. Our next task is to use a MCU to pulse those same address lines with accurate timing.
The display is controlled column by column, using an array of h-bridges to configure each pixel in the column
The board that came with the displays is a generic MCU (H8)which we are going to reverse engineer and replace with a modern MCU
Photo gallery: https://photos.app.goo.gl/47nwBdrXxcoKn3jY8
https://docs.google.com/document/d/1CUAwdkxpGrkr4xf47PyitDyd0ukrCAkWJyJCvSQuNrw/edit?usp=sharing
Forum with similar setup
https://forums.adafruit.com/viewtopic.php?f=8&t=21599
Demonstration of custom controller - no details provided
http://www.youtube.com/watch?v=IcN_nGvcxeU
Custom arduino controller with info
http://www.youtube.com/watch?v=k7PlNs5B3pl
Github with code and circuit (below)
https://github.com/aacarioca/FlipDotDisplayController
Documented project with similar panels
https://engineer.john-whittington.co.uk/2017/11/adventures-flippy-flip-dot-display/
https://www.instagram.com/p/BfHD7dklxxZ/