Maker Tim Alex Jacobs has put collectively an ultra-compact steampunk-inspired secondary show, pushed totally utilizing the Show Information Channel (DDC) of an HDMI port — “a complete hack and by far the worst technique to get a second monitor,” Jacobs admits.
“In an HDMI cable, nestled amongst the high-speed differential pairs, there’s an exceedingly gradual I2C bus,” Jacobs explains — the Show Information Channel, initially designed for speaking supported configurations between show outputs and gadgets. “Tiny OLED dot-matrix shows usually have an I2C controller, so I had the thought to attempt to plug one instantly into an HDMI port. Hilarious! Let’s do it.”
That undertaking, accomplished earlier this yr, led to DDC-OLED — an open supply device for Linux which turns an SSD1306 OLED show right into a tiny secondary show for X11. Initially, Jacobs was content material to think about the undertaking completed when an OLED lastly displayed an image — however an itch resulted in additional tinkering, enhancing the software program to assist simpler framebuffer setup, configurable brightness, elective dithering, and partial body updates.
Then got here the steampunk facet. “What’s a sillier improve for the silliest show than making it steampunk? However I by no means went in for sticking golden spray-painted gears on my hat,” Jacobs explains. “Once I discuss steampunk, I discuss milled brass and knurling.
“Except the USB Mild, from which I salvaged the flexible gooseneck factor, all the components have been sourced from bits I had mendacity round. This can be very satisfying to go from preliminary concept (of ‘flexible gooseneck milled brass HDMI DDC show’) to completed prototype the next day.”
The show makes use of a gooseneck conduit salvaged from a USB gentle to face freely with customized positioning. (📷: Tim Alex Jacobs)
Mentioned completed prototype, designed in SCAD, homes an off-the-shelf SSD1306 OLED panel inside a two-part brass housing held along with larger-than-planned M2 bolts. This connects to the DDC and energy pins of an HDMI connector by way of the aforementioned gooseneck, permitting the show to be positioned above the desk and angled as required.
“There might have been a intelligent technique to assemble the connector, possibly utilizing tiny bolts and threaded holes, however I made a decision to go along with a single be a part of that’s hot-glued in place as a result of it was the funniest possibility. The wonderful thing about ‘steampunk’ is that you do not have to wash your solder joints. The messy flux residue simply provides to the look,” Jacobs jokes.