I2C From Your VGA Port

Breakout board for VGA to I2C

VGA, DVI, and HDMI ports use Display Data Channel (DDC) to communicate with connected displays. This allows displays to be plug and play. However, DDC is based on I2C, which is used in all kinds of electronics. To take advantage of this I2C port on nearly every computer, [Josef] built a VGA to I2C breakout.

This breakout is based on an older article about building a $0.25 I2C adapter. This adapter hijacks specific lines from the video port, and convinces the kernel it’s a standard I2C device. Once this is done, applications such as i2c-tools can be used to interact with the port.

[Josef] decided to go for overkill with this project. By putting an ATmega328 on the board, control for GPIOs and LEDs could be added. Level shifters for I2C were added so it can be used with lower voltage devices. The end product is an I2C adapter, GPIOs, and LEDs that can be controlled directly from the Linux kernel through an unused video port.

Arduino Day is Today

arduino-day-2014

Did you know today is Arduino day? A day to pull that little teal board out of the bin and blink some LEDs or dive deeper to challenge your skills. There’s a map of local events, but unless you’re near Italy (the birthplace of the movement) events are a bit hard to find.

There can be a lot of hate for Arduino around here, but we consider it the gateway drug to learning hardware design so why not support wide-adoption of the platform? We’ve even seen Hackaday-associated projects adopting compatibility. Both the Mooltipass and the FPGA shield projects have the platform in mind. Break down the assumption that electronics require mythical-levels-of-wizardry to toy with and we’ll be on our way to a world filled with hardware hackers. If you do want to get some really cheap boards to hand out Sparkfun has Pro Mini’s for $3 today, as well as some other deals [Thanks Jeff].

Are you still unconvinced and ready to rage in the comments? Before you do head on over to our Arduino anger management site to exercise some of that aggression.

Impressive dev boards for your STM32 dev boards

stm32-discovery-breakout-boards

It seems there are a lot of people who have the same complaint about the STM32 Discovery boards; it can be difficult to add external hardware to them. Don’t get us wrong, we appreciate all of the pins being broken out (as opposed to the Stellaris Launchpad which we think has too few available). Here’s [Scot Kornak's] solution to the problem. He created three different baseboards which the STM32 Discovery plugs into. Each is for a different model of dev board: the VL, F3, and F4. But he also thinks the baseboard we saw in this other project is a good choice for an F4 solution.

These large PCB add-ons bring functionality in two different ways. The first is by using expandable ports for drop in modules like serial communications connectors or Analog/SPI/I2C modules. For us, the second method is the most desirable. He routes each GPIO port to a 2×8 header and uses IDC cables (rainbow cable in these images) to connect them to a breadboard. Seeing this makes us wish STM had used discreet clusters of 16 pins instead of those super long dual pin headers.

UDP between STM32-F4 Discovery boards

stm32-f4-udp

[The Backwoods Engineer] tested out a new accessory kit for the STM32-F4 Discovery board. The image above shows two boards communicating with the UDP protocol. Notice the extra PCB into which each Discovery board has been plugged. This is a third-party add-on which adds Ethernet, RS-232, SD card slot, and a connector for LCD or Camera. We’ve had one of these F4 Discovery boards on hand for a while and haven’t figured out a good way to connect external hardware to the huge dual pin-headers. This doesn’t solve the problem — the base board also includes dual headers to break-out all the pins — but having Ethernet, serial, and SD certainly reduces the need to add all that much more. The other drawback to the hardware is that the sample firmware is targeted at the IAR Embedded Workbench which is neither free, nor in the realm of affordable for hobbyists.

The NIC used on the baseboard has auto-crossover capabilities so the boards were connected using a regular Cat6 patch cable. This example has the boards constantly sending UDP packets with the module on the right reporting status information to a terminal via the serial connection.

Portable gaming console uses SSD1289 and Propeller

building-a-portable-video-game

[Samir] dabbles in hobby electronics and decided to put his skills to the test by building this portable gaming console (Note: this site uses an HTTPS address which cannot be used through Google Tranlator. It does work for the Chrome browser translator). The image above is a screenshot from his Breakout-style game. The paddle at the bottom is controlled with the touchscreen. You move it back and forth to keep the ball from traveling past the bottom edge (it bounces off of the red borders on the sides and top).

The main PCB is larger than the 3.2″ LCD footprint, but [Samir] made sure to include a lot of peripherals to make up for it. The board sports a Parallax Propeller chip to run the games. It interfaces with the SSD1289 screen (this is a cheap and popular choice) but that really eats up a lot of the IO pins. To control the game the touchscreen can be used as we’ve already mentioned. But there are two other options as well. There is an expansion port which uses a shift register (74HC165) to serialize the input. For prototyping this allowed [Samir] to use an Atari joystick. He also rolled a Bluetooth adapter into the project which we would love to see working with a Wii remote. Rounding out the peripherals are an SD card slot, audio jack for sound, and an RTC chip for keeping time.

There are several videos included in the post linked above. After the break we’ve embedded the game-play demo from which this screenshot was taken.

[Read more...]

OLED name badge with rechargeable LiPo cell

oleduino-name-badge

Here’s a project that let [Rick Pannen] try his hand with an OLED display and a rechargeable power source. He calls it OLEDuino which is a mashup of the display type and the Arduino compatible chip running the whole thing. He figures it will serve nicely as a geeky name badge but also ported a Breakout type game to play when he’s bored.

The project is an inexpensive way to attempt a more permanent trinket than simply using Arduino and a breadboard. [Rick] sourced the OLED display and USB LiPo charging cable on eBay. The ATmega328 hiding below the display is being driven from the 3.7V LiPo cell without any power regulation. The four buttons at the bottom provide the only user input but it should be more than enough for a few simple tricks.

Head over to his code repo for a bit more information. The schematic and board are both Eagle files. We generated an image of the schematic and embedded it after the break if you want to take a quick look at how simple the hardware really is.

[Read more...]

Hackaday Links: November 15, 2012

Another way to break out dual pin headers

[Uwe] wrote in to share his technique for breaking out dual pin headers. He uses two single pin headers, a piece of protoboard, and a dual row pin socket to make an adapter. This is removable where the other method we saw this week was not.

Web-based slide show hack

Wanting to use an old Android tablet as a digital picture frame, [Gordon] coded up a simple way to use an HTML page to scan your picture directories to feed a rotating background image.

The simplest hot plate

For his chemistry experiments [Charlie] is using a plain old clothes iron for a hot plate. he simply clamps it upside down to the bench. It doesn’t have any stirring abilities, but we already have an old iron in the shop which we use for toner transfer so we’ll have to keep this in mind if we ever need to heat chemicals (might be a good way to warm etchant).

A charging VU meter

This Cambrionix series8 universal charger has columns of LEDs that are animated when a device is charging. [Steve Tyson] works for the company and has had some fun messing with the firmware. He’s showing off the display as a VU meter.

Game Boy knockoff teardown

This wide-form-factor Game Boy is a knockoff from way back when the original system hit the market. You won’t want to miss this lengthy post that takes a look at what’s inside. [Thanks Neil]