AVR Minecraft Server Lets You Toggle Pins From The Virtual World

November 16, 2012 by Mike Szczys 21 Comments

Wanting to test his skills by building a webserver [Cnlohr] decided to also code a Minecraft server which allows him to toggle pins from inside the game. The rows of switches seen above give him direct access to the direction register and I/O pins of one port of the ATmega328.

The server hardware is shown in the image above. It’s hard to tell just from that image, but it’s actually a glass substrate which is [Cnlohr’s] specialty. He uses an ENC424J600 to handle the networking side of things. This chip costs almost twice as much as the microcontroller next to it. But even in single quantities the BOM came in at under $20 for the entire build.

In the video after the break [Cnlohr] and a friend demonstrate the ability for multiple users to log into the Minecraft world. The simulation is fairly bare-bones, but the ability to affect hardware from the game world is more exciting than just pushing 1s and 0s through some twisted pairs.

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In-depth Comparison At STM32 F3 And F4 Discovery Boards

November 15, 2012 by Mike Szczys 5 Comments

The STM32 F3 and F4 Discovery boards have been around for a while now. We’ve looked at both separately and they’re impressive dev boards for the price. Now can get a closer look at each from this in-depth comparison of the two Cortex-M4 development tools.

To start off, both of the boards have the same size and footprint (there are two dual-row pin headers which break out the connections to the ARM chip). Fundamentally the F3 and F4 chips have a different level of features, but the boards themselves are aimed at different applications as well. The F3 series of microcontrollers looks to be more affordable than the F4, containing less program memory, no Ethernet capability, and only one USB port. But both have hardware floating-point abilities and they’re blazing fast. The boards offer a MEMS accelerometer for prototyping. But the Discovery-F3 also contains a gyroscope while the Discovery-F4 provides audio hardware like a microphone, and DAC.

If you want to use a Linux box to develop with these tools you might find this guide helpful.

Variometer Build For Gliding Aircraft

November 15, 2012 by Mike Szczys 24 Comments

If you’re flying through the air in a non-powered vehicle your rate of descent is something that you want to keep any eye one. With that in mind, [Adrian] decided to design his own Variometer (translated) what will have a place in the cockpit next to the other instrumentation. It emits a pitch whose frequency is dictated by the rate at which altitude is being lost or gained.

He went with a PIC 24FJ64 microcontroller to drive the device. It’s reading data from an MS5611 barometric pressure sensor. This measures changes in air pressure associated with a change in altitude. As a user interface he chose one of SparkFun’s Nokia 5110 LCD screen breakout boards. He also went with one of their boost converts which lets him power the device from just one battery cell. The case itself is cut from several layers of plastic using a CNC mill.

In the video after the break you can see how sensitive the device is. Moving it just a few feet up or down has an immediate effect on the sound and the displayed data.

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SquareWear Sewable Microcontroller Board

November 15, 2012 by Mike Szczys 11 Comments

If you’re into adding electronics to your wearable items this little board will be of interest. The 1.6″x1.6″ board is called SquareWear and comes in several different flavors.

It may be a bit of a surprise that this is not an Arduino compatible board. [Ray] tried a few projects with PIC microcontrollers and ended up really liking them. He chose to go with the PIC 18F14K50 for this project. The chip has USB functionality and is running a bootloader. He thinks this makes it easier to work with over a wide range of computers than the Lilypad (a sewable Arduino compatible board which sometimes runs into FTDI driver issues the first time you try to program it).

We like the fact that it is open source. As we mentioned earlier, it comes in a few different flavors. There is a red or white version that uses a LiPo battery, and one that is driven from a CR2032 coin cell. If you’re working on a small project to which you would like to add a rechargeable battery this will serve as a cheap and easy reference design.

[via Adafruit]

Put Your Dev Board To Work As A Demoscene Display

November 14, 2012 by Mike Szczys 4 Comments

If you’re looking for a way to push your comfort zone with that slick new microcontroller you’ve been working with we think [Morgan Gangwere] has the answer. He took his chipKit development board and used it as a demoscene platform.

Demoscene refers to audio and visual demos written to squeeze as much entertainment out of a given platform as possible. We’ve seen demos for a lot of different platforms; for instance, here’s a Propeller chip demo. But this use of the onboard OLED screen brings a smile to our faces. With well under 100 lines of code [Morgan] implemented several different video effects (the music heard in the clip after the break is not being produced by the board). There is a star field which serves as the background. Over the top of it a scrolling message is displayed following a sine wave shape. The speed at which it scrolls is set by the trimpot, which you can see adjusted about 50 seconds into the clip.

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Make Dual Pin Header Footprints Into Breadboard Friendly DIP

November 13, 2012 by Mike Szczys 28 Comments

[John] wrote in with a solution to a prototyping issue that has vexed us for quite some time. Above you can see the DIP friendly solution for dual-row pin headers which he came up with. With just a bit of easy soldering he now has a breadboard friendly device for prototyping.

He starts by soldering a dual row pin header on the board, then clips off all of the legs on the outside row. The row of legs that remain are then inserted into one side of the trench on his breadboard. The other side of the trench has a single row pin header, and he solders them to the outer row on the breakout board using another single pin header aligned horizontally. This isn’t a 100% convenient solution, as it’s still pretty hard to get your jumper wires in the breadboard on the side covered by the breakout board. But if you plan in advance you can place your wires first, then plug in the development board.

Here [John] is working with TI’s eZ430-RF2500 board. We’d like to go back and remove the dual pin socket we soldered on our eZ430-F2013, replacing it with this style of pins.

Cornell ECE 4760 Lecture Videos Now Online

November 13, 2012 by Mike Szczys 5 Comments

Whenever we hear about ECE 4760 we take notice. That’s because a ton of fantastic hacked together projects have resulted from the class. It’s offered at Cornell University and focuses on designing projects based on microcontrollers. We look at it as a ‘how to connect everything to your microcontroller’ guide. The good news for you is that 34 lecture videos from the Spring 2012 ECE 4760 class are now available to watch for free online. When coupled with the course webpage itself (which outlines the reading, labs, and homework) this turns into an opportunity to work through the entire course on your own schedule.

If you need a brief preview, here’s a couple random things we’ve seen as final projects from the course: a digital saxophone, a handwriting decoder, and a haptic feedback unit for building your biceps.

We’re still working our way through the Nand2Tetris project, but we’re putting these lectures on our watch list for later.

[via Reddit]