What Could Go Wrong? I2C Edition

July 19, 2016 by Elliot Williams 53 Comments

I should really like I2C more than I do. In principle, it’s a brilliant protocol, and in comparison to asynchronous serial and SPI, it’s very well defined and clearly standardized. On paper, up to 127 devices can be connected together using just two wires (and ground). There’s an allowance for multiple clock-masters on the same bus, and a way for slaves to signal that the master needs to wait. It sounds perfect.

In reality, the tradeoff for using only two wires is a significantly complicated signalling and addressing system that brings both pitfalls and opportunities for debugging. Although I2C does reduce the number of signal wires you need, it gets dangerous when you have more than a handful of devices on the same pair of wires, and you’re lucky when they all conform to the same standard. I’ve never seen twenty devices on a bus, much less 127.

But still, I2C has its place. I2C was designed to connect up a bunch of slower, cheaper devices without using a lot of copper real estate compared to its closest rival protocol: SPI. If you need to connect a few cheap temperature sensors to a microcontroller (and their bus addresses don’t clash) I2C is a great choice. So here’s a guide to making it work when it’s not working.

Continue reading “What Could Go Wrong? I2C Edition” →

New Part Day: ST’s 32-Bit 3D Printer Controller

July 19, 2016 by Brian Benchoff 57 Comments

There are a few 32-bit ARM-based 3D printer controller boards out there such as the Smoothieboard, the Azteeg X5 mini, [Traumflug]’s Gen5 electronics, whatever board is in the Monoprice MP Mini Select, and several others I will be criticized for not mentioning. All of these ARM boards provide smoother acceleration, better control, and ultimately better prints from whatever 3D printer they’re controlling. Now, out of the blue, there’s a new board. It’s an evaluation board from ST — much like those famous Discovery boards — that sells itself as a plug and play solution for 3D printers.

The heart of this board is an STM32F401 — not the king of the STM32 line or the fastest ARM microcontroller, but anything faster or more capable will add considerably more to the BOM for this board. This controller board features six of ST’s L6474 motor drivers with enough current for some beefy NEMA 23 stepper motors , a multi-zone heated bed, and connections for a WiFi module and external LCD and keypad. You can buy this board right now for $118. This board isn’t a game changer, but it is evidence the game has been changed.

As with all 3D printer controller boards, there are a few aspects that will leave users wanting more. This is a board meant for 12V heaters (except for the bed, which has a 24V, 20A output), and the stepper drivers can only go up to 16 microsteps. That said, there’s not much else to complain about. This offering comes with a 32-bit firmware called Marlin4ST. From a quick perusal, it looks like the familiar configuration.h is still there, and still does what it’s supposed to do.

This ST Discovery board is extremely capable, available now, and relatively cheap, but that’s not really the big story here. What this board represents is a reference design and working firmware for a 32-bit ARM-based printer controller. That’s the future, and with this board the future might come a little sooner.

Thanks [jagerboots] for sending this one in.

Hackaday Prize: 20 Projects That Make Us All Citizen Scientists

July 18, 2016 by Brian Benchoff 8 Comments

We live in a time of unparalleled access to technology and this has the power to make life better for everyone. Today we are excited to announce twenty spectacular builds that use access to technology to move scientific exploration within the reach of all. These are the winners of the Citizen Scientist challenge of the 2016 Hackaday Prize. Themes tackled in this round include blood glucose monitoring, insole sensing for analyzing your footfalls, lab equipment like automated microscopy, sensors to measure the world around us, and more.

The winners for the Citizen Scientist portion of the Hackaday Prize are, in no particular order:

The Hackaday Prize is the greatest hardware competition on earth. We want to see the next great Open Hardware project benefit everyone. We’re working toward that by recognizing people who build, make, and design the coolest and most useful devices around.

These twenty projects just won $1000 and will now move on to the final phase of The Hackaday Prize, to be judged by our fourteen celebrity judges. Awesome! Now get to work: there’s a lot the hackers behind these projects need to do before the final judging in October where they’ll compete for the grand prize of $150,000 and four other top prizes.

If your project didn’t make the cut, there’s still an opportunity for you to build the next great piece of hardware for The Hackaday Prize. The Automation Challenge is currently under way. It encourages everyone to build devices that make your life easier.

Automate your life; build a device that makes your breakfast, a robot to mow your lawn, or software that does your taxes. Build a device that automatically tracks laundry detergent, automates washing the dishes, or a robot that obeys every command.

Like the Design Your Concept, Anything Goes, and Citizen Science rounds of The Hackaday Prize, the top twenty projects will each win $1000, and move on to the Hackaday Prize finals for a chance to win $150,000 and a residency at the Supplyframe DesignLab in Pasadena.

If you don’t have a project up on Hackaday.io, you can start one right now and submit it to The Hackaday Prize. If you’re already working on the next great piece of hardware design, add it to the Automation challenge using the dropdown menu on the sidebar of your project page.

Hackaday Links: July 17, 2016

July 17, 2016 by Brian Benchoff 23 Comments

There’s going to be a new Nintendo console for Christmas! It’s the NES Classic Edition. It looks like a minified NES, with weird connectors that look like the connector for the Wii Nunchuck. There are no other details.

A site called “Motherboard” reports assembling a computer is too hard and a ‘nerve-wrecking [sic]’ process. Tip of the stovepipe to the Totalbiscuit.

When I was in elementary school, the playground had a twenty foot tall metal slide that faced South. During my time there, at least three of my classmates fell off it, and I distinctly remember the school nurse’s aid running past me on the playground with a wheelchair. There wasn’t soft mulch or the weird rubber granules under this slide – just hard, compacted dirt. This slide was awesome, even if it was torn down when I was in third grade. [Brandon Hart]’s kid’s won’t look back fondly on their youth with experiences like these; he built a water-cooled slide in his backyard. He’s getting an 80°F ΔT with a trip to Ace Hardware, probably $20 in fittings, and a drill. Neat.

This is probably better suited for an ‘Ask Hackaday’ column, but [Arsenijs] has run into a bit of a problem with his Raspberry Pi Project. He’s trying to use a planarized kernel module to obfuscate the SPI bus, but he can’t do that because of a oblivated drumble pin. He could, of course, deenumerate several of the GISP modules, but this would cause a buffer underflow and eventually wreck the entire cloudstack. I told him he should use Corrosion, but he seems dead set on his Hokey implementation. If anyone has any ideas, get the glamphs and put it on the grumbo.

The Owon SDS7102 oscilloscope is a small, cheap, two-channel scope that is impressive for its price but noisier than you would expect. This scope has been thoroughly reverse engineered, and now Linux is running on this scope. This Linux scope has a working VGA display, USB host, USB device, Flash, and working Ethernet. The entire analog front end has been reversed engineered, and somehow this is now the most open oscilloscope you can buy.

The ESP32 is Espressif’s followup to their very popular ESP8266 WiFi module. The ESP32 will be much more powerful and include Bluetooth when it’s released in August. Until then, [Pighixxx] has the complete pinout for the ESP32.

Hacklet 116 – Audio Projects

July 16, 2016 by Adam Fabio 5 Comments

If the first circuit a hacker builds is an LED blinker, the second one has to be a noisemaker of some sort. From simple buzzers to the fabled Atari punk console, and guitar effects to digitizing circuits, hackers, makers and engineers have been building incredible audio projects for decades. This week the Hacklet covers some of the best audio projects on Hackaday.io!

We start with [K.C. Lee] and Automatic audio source switching. Two audio sources, one amplifier and speaker system; this is the problem [K.C. Lee] is facing. He listens to audio from his computer and TV, but doesn’t need to have both connected at the same time. Currently he’s using a DPDT switch to change inputs. Rather than manually flip the switch, [K.C. Lee] created this project to automatically swap sources for him. He’s using an STM32F030F4 ARM processor as the brains of the operation. The ADCs on the microcontroller monitor both sources and pick the currently active one. With all that processing power, and a Nokia LCD as an output, it would be a crime to not add some cool features. The source switcher also displays a spectrum analyzer, a VU meter, date, and time. It even will attenuate loud sources like webpages that start blasting audio.

Next up is [Adam Vadala-Roth] with Audio Blox: Experiments in Analog Audio Design. [Adam] has 32 projects and counting up on Hackaday.io. His interests cover everything from LEDs to 3D printing to solar to hydroponics. Audio Blox is a project he uses as his engineer’s notebook for analog audio projects. It is a great way to view a hacker figuring out what works and what doesn’t. His current project is a 4 board modular version of the Big Muff Pi guitar pedal. He’s broken this classic guitar effect down to an input board, a clipping board, a tone control, and an output stage. His PCB layouts, schematics, and explanations are always a treat to view and read!

Next we have [Paul Stoffregen] with Teensy Audio Library. For those not in the know, [Paul] is the creator of the Teensy family of boards, which started as an Arduino on steroids, and has morphed into something even more powerful. This project documents the audio library [Paul] created for the Freescale/NXP ARM processor which powers the Teensy 3.1. Multiple audio files playing at once, delays, and effects, are just a few things this library can do. If you’re new to the audio library, definitely check out [Paul’s] companion project
Microcontroller Audio Workshop & HaD Supercon 2015. This project is an online version of the workshop [Paul] ran at the 2015 Hackaday Supercon in San Francisco.

Finally we have [drewrisinger] with DrDAC USB Audio DAC. DrDac is a high quality DAC board which provides a USB powered audio output for any PC. Computers these days are built down to a price. This means that lower quality audio components are often used. Couple this with the fact that computers are an electrically noisy place, and you get less than stellar audio. Good enough for the masses, but not quite up to par if you want to listen to studio quality audio. DrDAC houses a PCM2706 audio DAC and quality support components in a 3D printed case. DrDAC was inspired by [cobaltmute’s] pupDAC.

If you want to see more audio projects and hacks, check out our new audio projects list. See a project I might have missed? Don’t be shy, just drop me a message on Hackaday.io. That’s it for this week’s Hacklet, As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

Retrotechtacular: The US Air Force Has The Biggest Fleet

July 15, 2016 by Brian Benchoff 27 Comments

When it comes to the superlatives of aviation, there are aircraft larger than the C-5 Galaxy. [Howard Hughes]’s Spruce Goose has the largest wingspan, and the Soviet and now Ukranian Antonov AN-225 Mriya has the largest cargo capacity. When it flies in the next year or so, Scaled Composites Stratolaunch – a twin-hulled beast of a plane designed to haul rockets up to 30,000 feet – will be the aircraft with the largest wingspan and the greatest cargo capacity.

These superlatives, while completely accurate, fail to realize these huge planes are one of a kind. There is no plan to build a second Stratolaunch, and the second airframe for the AN-225 is rusting away in a field. If you want to find a fleet of enormous aircraft, there’s only one contender: the C5 Galaxy, the largest plane in the US Air Force inventory.

This video, from the USAF Archives circa 1968, goes over the design, construction, and operation of the C5 Galaxy. It covers the program beginnings, the shortcomings of earlier aircraft, and – of course – completely disregards the initial problems of the C5.

Continue reading “Retrotechtacular: The US Air Force Has The Biggest Fleet” →