LED Display

LED display @ Maker Faire

LED display @ Maker Faire

Last year I mentioned a long term project I'm working on: A huge LED display built out of 32x32 LED RGB matrix modules driven by a BeagleBone Black, which could drive the display like a usual monitor using a framebuffer driver. After many months and just right before Maker Faire 2015 in Hanover I managed to bring the project in a presentable state. This article shall give an overview over the project. Continue reading

Maker Faire Hannover 2015

Dieses Wochenende fand die dritte Maker Faire in Hannover statt und nachdem ich 2013 und 2014 nur als Besucher vor Ort war, habe ich mich dieses Jahr auf dem Stand des Chaos Computer Club Hannover als Maker versucht. Bei uns am Stand gab es neben einem Lötworkshop viele Bastelprojekte zu sehen: Unter anderem hatten wir verschiedene selbst-gebaute Tastaturen, Snake auf Flipdot Displays, Multiplayer Tetris auf einem LED Laufschriftmodul, einen LED-Effekt-Koffer, meine Time Circuits und mein LED Display dabei. Das am Stand viel blinkte und es viel auszuprobieren gab, waren wir die ganze Zeit von vielen Kids und Junggebliebenen belagert, welche entweder für sie neue Spiele (Die 'Jugend' kennt kein Tetris mehr) oder Altbekanntes ausprobieren wollten.
Continue reading

Upgrading HP 6060B DC Electronic Load with front binding posts

HP 6063B Front Binding Posts

HP 6063B Front Binding Posts

A few weeks ago I scored an HP/Agilent/Keysight 6060B DC Electronic Load on eBay. Unfortunately most of these come without front binding posts as they are optional (Option 020) and have to be paid extra for. As I'm using this as a bench DC load and not in a rack-mounted test setup I wanted to have these. Luckily I had access to a HP/Agilent/Keysight 6063B DC Electronic Load with front binding posts, which is basically the same DC load with just less current and more voltage specs. Continue reading

7-segment Charlieplexing

A few weeks ago I bought the ATLYS FPGA development board from Digilent. Unlike my other two FPGA development boards (NEXYS3, BASYS2) the ATLYS does not have a 7-segment display onboard. As I often use this during debugging I wanted to add some external 7-segment display to the ATLYS board. The ATLYS boards provides two connections for add-on boards: A high-density Vmod port and a 8-pin Pmod™ port. As I'm planning to use the Vmod port for other stuff I wanted to use the Pmod™ port for the 7-segment display.

On my other two FPGA bords the 7-segment display is directly connected to the FPGA. The 4-digit 7-segment display has four anodes (one per digit) and eight cathodes (one per segment plus the decimal point) totalling in twelve pins. The display control has to be multiplexed within the FPGA. As the Pmod™ connector has only eight pins this kind of control mechanism would not work. So the most obvious alternative to send the data for pins serially and to use serial to parallel converters on the extension board. However I wanted to avoid using a lot of ICs on the boards so I went for an alternative approach: Charlieplexing. Continue reading