I’ve been playing around with representing textual information with 7-segment displays. The nifty thing about 7-segment displays is they are ubiquitous, cheap, and easily addressable with IC chips such as the (mighty) ULN2003a.

In my immediate explorations, I find that the following letters are not possible using a 7-seg:

M, W, V, K , X, Q, Z

This is considering that it is okay to use lowercase letters to “cheat”.

For example, the word “BURNT” could be written :

|_Â | |Â _Â _Â |_
|_| |_| |Â | | |_

I don’t really like the solution for “N”, but at least it works. It’s a shame about the letter “M”, as it has a somewhat high letter frequency! Here’s a chart of the letter frequencies of the 7-segment “orphans” (based on Wikipedia data):

m 2.41%
w 2.36%
v 0.98%
k 0.77%
x 0.15%
q 0.10%
z 0.07%

The next plan is to develop a display that can handle all the letters with as few segments as possible (inspiration from Josh Nimoy). In the meantime, I whomped up a little Processing program to randomly illuminate the various segments of a 7-seg display…click to view the program: