This is a homage to the old timey flip flap boards used in train stations to announce train arrival and departure times. Each letter in such boards had to be flipped through its entire deck of flip cards before it could settle down to displaying its letter of the final message.
They still sell boards like this at
This app lets you program your phone to do that.
(Sample Announcement courtesy of Jack Benny)
This app requires an ordered list of all UTF-8 symbols, to drive the board.
I found one at Columbia University's Kermit Project, courtesy of
Frank da Cruz, The Kermit Project, Columbia University, 25 June 2003
For the purposes of this project, all we need is the symbol between the [ and the ] on each line, in that order.
Here's the loading order:
The UTF40 character list is the end result, for use in the Clock Timer.
Clock Timer code:
This is how the flipping sequence is initialized and started.
Each Clock Timer cycle, we have to run through each letter position of our message, replacing that letter with either itself or the current UTF8 flip character, whichever comes first in the UTF8 character list. After displaying the latest iteration of the message, we advance the index into the UTF8 character list for the next Clock1.Timer cycle.
This global variable is needed to keep track of how far down the UTF8 character list we have reached flipping the message display characters.
Source code:
FlipFlapBoard.aia (131.0 KB)
All blocks:
