Good USB – Protecting Your Ports With Two Microcontrollers

March 2, 2017 by Brian Benchoff 43 Comments

If you’ve ever needed an example of why you should not plug random USB peripherals into your computer, you need only look at BadUSB. The BadUSB attack relies on the fact that the microcontroller inside every USB device is a black box. If you plug a USB thumb drive into your computer, the microcontroller could quickly set up an additional network interface, forward all your traffic to the attacker’s server, and still keep serving up all those files and documents on the drive. Do you want a thumb drive that attaches a virus to every file? Bad USB can do that.

Until now, there is no cure or fix for a device using an implementation of BadUSB. [Robert Fisk] just came up with the first prophylactic USB device, designed to keep BadUSB off your computer. He’s calling it USG, and it’s basically a hardware firewall for USB devices.

The basic design of the system goes something like this: take an ARM microcontroller with a USB host port, take another microcontroller with a USB device port, and have these devices talk to each other over SPI. The command protocol between these two microcontrollers is very simple, and thus decreases the attack surface.

[Robert] is building USG dongles, but in the spirit of Open Hardware and verifiable hardware, he’s also released a design based on two dev boards wired together. This DIY version is basically two STM32F4 dev boards smashed together with bodge wires. The total cost – less solder and a JTAG programmer – is about $50 USD. No, it doesn’t look as pretty as [Robert]’s commercial version of USG, but it does the same job of keeping your computer safe from BadUSB devices.

ESP32 Tutorials

March 1, 2017 by Al Williams 24 Comments

The ESP8266 has become one of those ubiquitous parts that everyone knows. However, the new ESP32 has a lot of great new features, too. If you want to take the ESP32 for a spin, you should check out [Neil Kolban’s] video series about the device. When we say series, we aren’t kidding. At last count, there were nineteen videos. Some are only a few minutes long, but some weigh in at nearly twenty minutes and the average is somewhere in between.

The topics range from setting up tools and using Eclipse and GDB. There are also tutorials on specific tasks like PWM, analog conversion, real-time operating systems, and more.

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Understanding DMA

February 28, 2017 by Al Williams 17 Comments

In the world of computers, the central processing unit (CPU) is–well–central. Your first computer course probably explained it like the brain of the computer. However, sometimes you can overload that brain and CPU designers are always trying to improve both speed and throughput using a variety of techniques. One of those methods is DMA or direct memory access.

As the name implies, DMA is the ability for an I/O device to transfer data directly to or from memory. In some cases, it might actually transfer data to another device, but not all DMA systems support that. Sounds simple, but the devil is in the details. There’s a lot of information in this introduction to DMA by [Andrei Chichak]. It covers different types of DMA and the tradeoffs involved in each one.

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Jean-Luc PYcARD Is A Pocketable Python Development Platform

February 23, 2017 by Elliot Williams 11 Comments

It’s a good thing that a ridiculous pun and a screenprint of Jean-Luc Picard on the bottom of the board is enough to qualify for the 2017 Hackaday Sci-Fi Contest, because [bobricius]’s Python-plus-Arduino card and environmental sensor potpourri is very cool.

The PCB design itself is great. It’s got a gigantic LED array, cutout for a wrist strap, and an onboard USB plug so you can program it just by sticking it in your computer; it shows up as a USB mass storage device when you plug it in. The files that show up on the “drive” are Micropython code that you can edit, save, and then run directly on the device. You can hardly beat that for convenience.

And there’s a full complement of sensors: not one but two temperature and humidity sensors, including our recent favorite BME280, which also reads barometric pressure. (We suspect that makes it a tri-corder.) There’s a real-time clock, a buzzer, and some buttons. Want to add more sensors? I2C ports are broken out for your convenience.

Besides having Star Trek flair, this board would give the various educational platforms a run for their money: Micro:bit, we’re looking at you. Very cool indeed!

Microchip Launches New Family Of PICs

February 21, 2017 by Brian Benchoff 106 Comments

Over the last few years, we’ve seen projects and products slowly move from 8-bit microcontrollers to more powerful ARM microcontrollers. The reason for this is simple — if you want to do more stuff, like an Internet-connected toaster, you need more bits, more Flash, and more processing power. This doesn’t mean 8-bit microcontrollers are dead, though. Eight bit micros are still going strong, and this week Microchip announced their latest family of 8-bit microcontrollers.

The PIC16F15386 family of microcontrollers is Microchip’s latest addition to their portfolio of 8-bit chips. This family of microcontrollers is Microchip’s ‘everything and the kitchen sink’ 8-bit offering. Other families of PICs have included features such as a complementary waveform generator, numerically controlled oscillator, a configurable logic controller, power saving functionality and the extreme low power features, but never before in one piece of silicon.

This feature-packed 8-bit includes a few new tricks not seen before in previous Microchip offerings. Of note are power management features (IDLE and DOZE modes), and a Device Information Area on the chip that contains factory-calibrated data (ADC voltage calibration and a fixed voltage reference) and an ID unique to each individual chip.

As you would expect from a new family of PICs, the 16F15386 is compatible with the MPLAB Xpress IDE and the MPLAB Code Configurator, a graphical programming environment. The products in the family range from 8-pin packages (including DIP!) with 3.5kB of program Flash to 48-pin QFPs with 28kB of program Flash. The goal for Microchip is to provide a wide offering, allowing designers to expand their builds without having to change microcontroller families.

All of these chips can be sampled now, although the lower pin count devices won’t be available through normal means until next month.

Smaller Cheaper Arduino

February 21, 2017 by Al Williams 38 Comments

Well, honestly, [Michael Mayer’s] STM8 Arduino (called Sduino) isn’t actually much to do with the Arduino, except in spirit. The STM8 is an 8-bit processor. It is dirt cheap and has some special motor control features that are handy. There’s a significant library available for it. However, it can be a pain to use the library and set up the build.

Just like how the Arduino IDE provides libraries and a build system for gcc, Sduino provides similar libraries and a build system for the sdcc compiler that can target the STM8. However, if you are expecting the Arduino’s GUI or a complete knock off of the Arduino library, you won’t get that.

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Making Use Of Stellaris/Tiva Real-Time Clock

February 19, 2017 by Elliot Williams 8 Comments

If you’re at all like us, or like [Vadim], you’ve got a stash of development boards in a shoebox on a shelf in your closet. If you’re better organized that we are, it might even be labeled “dev boards”. (Ah well, that’s a project for another day.) Anyway, reach into your box and pull one out, and put it to use. Do something trivial if you need to, but a dev board that’s driving a silly blinker is better than a dev board sitting in the dark.

[Vadim]’s good example to us all is going to serve as the brains for an automated plant watering system. That’s a low-demand application where the microcontroller can spend most of the time sleeping. [Vadim]’s first step, then was to get a real-time clock working with the hibernation mode. There’s working code inline in his blog.

royale-with-cheese-pulp-fiction-2_12-movie-clip-1994-hd-6pkq_ebhxj4mkv-shot0001 — “I don’t know, I didn’t go into Burger King.”

If you use Arduino, you’ll feel at home in the Energia ecosystem. But it’s like ordering a Quarter Pounder with Cheese in Paris: Energia is a Royale with Cheese (YouTube) — it’s the little differences. And maybe that’s the point of the exercise; it’s always a good thing to try out something new, even if it’s only minimally different.

So grab that unused dev board off the shelf, struggle through the unfamiliar development environment and/or toolchain, but remember to keep an eye out for the sweet little differences. The more tools that you’re familiar with, the more solutions will spring to mind when you’re hacking on your next project.