Brent Marshall from Wright XM poked me a while back to help him out on a project for the CFL.

They wanted a huge interactive sign for the kickoff the next season. Wright XM definitely stepped up to the plate (um… yeah, wrong sports metaphor).

The sign consisted of 8 characters (#GREYCUP), and each letter was internally lit using addressable LEDs.

Brent needed a bit of help with the interaction between all of the letters. He already had all of the high level interaction done (e.g. scraping Twitter for the hashtags to update the letter colours, etc.). So, he called upon me to help with the low level stuff.

I used an old trick of using a single microcontroller as the master that would send simple serial messages with an embedded address. There was no data acking/error correction employed, as we only had a single transmitter, and no way to multiplex the incoming data from the slaves. RS232 was used in this case, since we didn’t have time/resources to switch over to RS422 or such, and we were well under 20m cable runs.

It worked quite well, despite a few cabling issues here and there, and in the end, I think Wright XM’s clients were happy.

Here is a video that Wright XM produced after the project to demonstrate what was done.

And here’s a shot of me working on the sign: