Transcending The Stack With The Right Network Protocol

April 9, 2019 by Maya Posch 14 Comments

The increase in network-connected devices the past years has been something of a dual-edged sword. While on one hand it’s really nice to have an easy and straight-forward method to have devices talk with each other, this also comes with a whole host of complications, mostly related to reliability and security.

With WiFi, integrating new devices into the network is much trickier than with Ethernet or CAN, and security (e.g. WPA and TLS) isn’t optional any more, because physical access to the network fabric can no longer be restricted. Add to this reliability issues due to interference from nearby competing WiFi networks and other sources of electromagnetic noise, and things get fairly complicated already before considering which top-layer communication protocol one should use. Continue reading “Transcending The Stack With The Right Network Protocol” →

The Joy Of Properly Designed Embedded Systems

March 20, 2019 by Maya Posch 32 Comments

The ages-old dream of home automation has never been nearer to reality. Creating an Internet of Things device or even a building-wide collection of networked embedded devices is “easy” thanks to cheap building blocks like the ESP8266 WiFi-enabled microcontroller. Yet for any sizable project, it really helps to have a plan before getting started. But even more importantly, if your plan is subject to change as you work along, it is important to plan for flexibility. Practically, this is going to mean expansion headers and over-the-air (OTA) firmware upgrades are a must.

I’d like to illustrate this using a project I got involved in a few years ago, called BMaC, which grew in complexity and scope practically every month. This had us scrambling to keep up with the changes, while teaching us valuable lessons about how to save time and money by having an adaptable system architecture.

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Buy Your Very Own Commercial Flight Simulator

January 21, 2019 by Maya Posch 25 Comments

If you happen to live near Phoenix, Arizona, have a spare US$10,000 or so kicking around, and have always fancied your own true-to-life commercial flight simulator, today is your lucky day. With just over a week to go on the auction, you can bid on a used flight simulator for a Bombardier CRJ200 regional jet airliner.

The CRJ200 jet was produced between 1991 and 2006, first being introduced in 1992 by Lufthansa. It’s a twin-engine design, with about 50 seats for passengers. With a length of more than 26 meters, 12,500 km (41000ft) ceiling, 785 km/h (487mph) cruising speed and a range of around 3,000 km (1864 mi) (depending on the configuration), it offers plenty of opportunities for the aspiring (hobbyist) pilot.

The auction stands at the time of writing at $4,400 offered and lasts until Monday, January the 28th. Local pick-up is expected, but the FAA-certified simulator comes complete with all of the manuals and the guarantee that it was 100% working before it was disassembled to ready it for auction. Just make sure that you have somewhere to put it before putting in that bid, and you could be the owner of a rig that would leave some of the best we’ve seen so far behind in the dust.

The Lost Art Of Steam Heating

November 18, 2018 by Maya Posch 51 Comments

We got pointed by [packrat] to a 2015 presentation by [Dan Holohan] on the history and art of steam heating systems. At the advent of central heating systems for entire buildings, steam was used instead of water or air for the transport medium. These systems were installed in landmark buildings including the Empire State Building, which still use them to this day.

A major advantage of steam-based heating system is that no pump is required: the steam will naturally rise up through the piping, condenses and returns to the origin. This can be implemented as a single pipe where condensation returns through the same pipe as the steam, or a two-pipe system where the condensate returns through its own pipe.

In the presentation, Dan walks us through his experiences working on many of these steam heating systems in major US buildings, the types of systems, fixes implemented by engineers long since dead and the particularities of maintaining these systems.

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Making PCBs With A Cutting Plotter

October 28, 2018 by Maya Posch 26 Comments

[LudwigLabs] is creating PCBs using copper foil and a cutting plotter (vinyl cutter). In this approach, it’s an additive process where instead of removing copper from a copper-clad board, the traces are cut out of copper foil and transferred to a solid backing surface (cardboard, fiberglass, etc.).

While similar to the use of copper tape laid out by hand, as covered by us last year, the big advantage of using a cutting plotter is that it allows one to create much more complicated traces similar to those you would expect to see on a factory-made PCB. Since cutting plotters translate a 2D design into very precise movements of the cutting blade, this allows for sharp angles and significantly thinner traces, allows designs from EDA software like KiCad or Altium to be quickly translated to physical boards.

Enterprising hackers might consider the possibility of using this approach to make two-sided, and even multi-layered boards. The copper is produced separately from the substrate which opens up the potential for using uncommon materials like glass or paper to host the circuits. The main limitations are the transferring of (very delicate) copper structures and creating vias without damaging the traces.

As a comparison with traditional PCB fab processes, the photo exposure and etching (or laser exposure and etching) process requires the creation of masks, UV exposing a board, etching, cleaning and so on. The simplicity of copper foil traces has led to many experimenting with this approach. Would you want to use this additive process, or are there refinements or alterations you would make?

Programming A RISC-V Softcore With Ada

October 8, 2018 by Maya Posch 9 Comments

We were contacted by [morbo] to let us know about a project on the AdaCore blog that concerns programming a PicoRV32 RISC-V softcore with Ada. The softcore itself runs on a Lattice ICE40LP8K-based TinyFPGA-BX FPGA board, which we have covered in the past.

The blog post describes how to use the Community edition of the GNAT Ada compiler to set up the development environment, before implementing a simple example project that controls a strip of WS28212b RGB LED modules. There are two push buttons changing the animation and brightness of the lights.

The source can be found at the author’s Github repository, and contains both the Ada source and the Verilog source for the PicoRV32 softcore. To build the project one needs the GNAT compiler, as well as the open-source iCE40 development tools to compile the softcore.

There is a video demonstrating the finished example project, that we’ve placed below the break.

Continue reading “Programming A RISC-V Softcore With Ada” →

Tiny WiFi-Enabled ARM MCU For Tiny Projects

October 2, 2018 by Maya Posch 62 Comments

Ever since the ESP8266 WiFi-enabled microcontroller came on the scene, it seemed like suddenly everyone came up with WiFi-enabled projects. But the ESP8266 is not the only game in town! Reader [PuceBaboon] notified us of a new product released by Seeed Studios: the imaginatively called Air602 WiFi Development Board.

The core of this board is the tiny WinnerMicro W600 MCU, which integrates a 32-bit ARM Cortex M3 CPU, along with dual UARTs, I2C, SPI and I2S interfaces, as well as a real-time clock (RTC). Add to this hardware crypto, seven I/O pins (five broken out on the development board) and you have a very capable WiFi-enabled MCU which can be programmed using the usual ARM development tools (e.g. Keil) using the provided SDK.

The W600 module can be bought by itself, in all its diminutive 12 mm x 10 mm glory, for a mere $1.90 as of time of writing – without antenna – as noted in [PuceBaboon]’s thoughts on this MCU and the development board.