Reverse engineering a cheap LED message marquee
posted May 19th 2011 10:01am by Mike Szczysfiled under: led hacks, Microcontrollers
[Hugo] went all out when sharing his findings while reverse engineering this small LED marquee. He purchased the 29×7 LED matrix for under $12 but was surprised to find that the USB connector wasn’t a standard type and didn’t come with a cable. He first soldered a standard connector in place and then set out to make the device do his bidding (translated).
What he accomplished can be seen in the video after the break. He can now connect to the device via a USB cable, sending it new messages and adjusting the speed at which it scrolls. He can also adjust the spacing between letters, reverse the scrolling direction, read the on-board buttons, and write the settings to the device’s EEPROM. This is all thanks to some alternative firmware that [Hugo] wrote for the ATmega88. You can download a copy of that code from the wiki page he put together (translated). We really appreciate the time he spent putting that page together. The wealth of information he gathered during the hacking process serves as an example of the best way to share your projects with the world.
From what I can tell he’s Not actually connecting over a USB cable. Just Serial. He mentions it could be possible with V-usb and i agree, with some modifications I think it would be very possible.