There are a host of PCB CAD tools at the disposal of the electronic designer from entry-level to multi-thousand-dollar workstation software. It’s a field in which most of the players are commercial, and for the open-source devotee there have traditionally been only two choices. Both KiCad and gEDA are venerable packages with legions of devoted fans, but it is fair to say that they both present a steep learning curve for newcomers. There is however another contender in the world of open-source PCB CAD, in the form of the up-and-coming LibrePCB.
This GPL-licensed package has only been in development for a few years. LibrePCB brought out its first official release a little over a year ago, and now stands at version 0.1.3 with builds for GNU/Linux, Windows, MacOS, and FreeBSD. It’s time to download it and run it through its paces, to see whether it’s ready to serve its purpose.
If imitation is the sincerest form of flattery, online creators are being sincerely flattered at an alarming rate these days. We Hackaday scribes see it all the time, as straight copy-pastes of our articles turn up on other websites under different bylines. It’s annoying, but given prevailing attitudes toward intellectual property rights, there’s very little point in getting upset about it anymore. But what if it’s hardware that’s being infringed upon?
Hacker and Tindie store proprietor [Brian Lough] recently ran into this problem with one of his products, but rather than get upset, he did a remarkably fair and thoughtful review of the knock-off. The board in question, a D1 Mini Matrix Shield, makes it a snap to use LED matrix panels in projects like his Tetris-themed YouTube sub counter. The knock-off came via Ali Express, with the most “flattering” aspect being the copy and the images on the Ali Express listing, some of which are pulled straight from [Brian]’s Tindie store. While the board’s layout is different, it’s pretty clear that it was strongly inspired by the original. And the changes they did make – like terminal choices and undersizing some traces – only serve to lower the quality of the knock-off. Surely this was a cost-cutting move, so they could undercut sales of the original, right? Apparently not – the knock off is more expensive. Yes, [Brian]’s board is a kit and the imitator is fully assembled, but it still begs the question of why?
Hats off to [Brian] for not only making a useful product, but for taking the time to engineer it properly and having the ambition to put it on the market. It’s a pity that someone felt the need to steal his work, but it seems to be a rite of passage these days.
Those of us who trawl the world of cheap imported goods will most often stay in our own comfortable zones as we search for new items to amaze and entertain us. We’ll have listings of electronic goods or tools, and so perhaps miss out on the scores of other wonders that can be ours for only a few dollars and a week or two’s wait for postage.
Just occasionally though something will burst out of another of those zones and unexpectedly catch our eye, and we are sent down an entirely new avenue in the global online supermarket.
Thus it was that when a few weeks ago I was looking for an inspection camera I had a listing appear from the world of personal grooming products. It seems that aural hygiene is a big market, and among the many other products devoted to it is an entire category of ear wax removal tools equipped with cameras. These can get you up close and personal with your ear canal, presumably so you can have a satisfying scoop at any accumulated bodily goop. I have a ton of electronics-related uses for a cheap USB close-up camera so I bought one of these so I could — if you’ll excuse the expression — get a closer look.
At the end of August I made the trip to Hebden Bridge to give a talk at OSHCamp 2019, a weekend of interesting stuff in the Yorkshire Dales. Instead of a badge, this event gives each attendee an electronic kit provided by a sponsor, and this year’s one was particularly interesting. The RC2014 Micro is the latest iteration of the RC2014 Z80-based retrocomputer, and it’s a single-board computer that strips the RC2014 down to a bare minimum. Time to spend an evening in the hackerspace assembling it, to take a look!
It’s An SBC, But Not As You Know It!
The kit arrives in a very compact heat-sealed anti-static packet, and upon opening was revealed to contain the PCB, a piece of foam carrying the integrated circuits, a few passives, and a very simple getting started and assembly guide. The simplicity of the design becomes obvious from the chip count, there’s the Z80 itself, a 6850 UART, 27C512 ROM, 62256 RAM, 74HCT04 for clock generation, and a 74HCT32 for address decoding. The quick-start is adequate, but there is also a set of more comprehensive online instructions (PDF) available.
Assembly of a through-hole kit is hardly challenging, though this one is about as densely-packed as it’s possible to make a through-hole kit with DIP integrated circuits. As with most through-hole projects, the order you pick is everything: resistors first, then capacitors, reset button and crystal, followed by integrated circuits.
I’m always a bit shy about soldering ICs directly to a circuit board so I supplemented my kit with sockets and jumpers. The jumpers are used to select an FTDI power source and ROM addresses for Grant Searle’s ROM BASIC distribution or Steve Cousins’ SCM 1.0 machine code monitor, and the kit instructions recommended hard-wiring them with cut-off resistor wires. There was no row of pins for the expansion bus because this kit was supplied without the backplane that’s a feature of the larger RC2014 kits, but it did have a set of right-angle pins for an FTDI serial cable.
Your Arduino Doesn’t Have A Development Environment On Board!
Having assembled my RC2014 Mini and given it a visual inspection it was time to power it up and see whether it worked. Installing the jumper for FTDI power, I attached my serial cable and plugged it into a USB port.
A really nice touch is that the Micro has the colours for the serial cable wires on the reverse side of the PCB, taking away the worry of getting it the wrong way round. A quick screen /dev/ttyUSB0 115200 to get a serial terminal from a bash prompt, hit the reset button, and I was rewarded with a BASIC interpreter. My RC2014 Micro worked first time, and I could straight away give it BASIC commands such as PRINT "Hello World!" and be rewarded with the expected output.
So I’ve built a little Z80 single board computer, and with considerably less work than that required for the fully modular version of the RC2014. Its creator Spencer tells me that the Micro was originally designed as a bargain-basement RC2014 as a multibuy for workshops and similar activities, being very similar to his RC2014 mini board but without provision for a Pi Zero terminal and a few other components. It lacks the extra hardware required for a more comprehensive operating system such as CP/M, so I’m left with about as minimal an 8-bit computer as it’s possible to build using parts available in 2019. My question then is this: What can I do with it?
So. What Can I Do With An 8-bit SBC?
My first computer was a Sinclair ZX81, how could it possibly compare this small kit that was a giveaway at a conference? Although the Sinclair included a black-and-white TV display interface, tape backup interface, and keyboard, the core computing power was not too far different in its abilities from this RC2014 Micro — after all, it’s the same processor chip. It was the platform that introduced a much younger me to computing, and straight away I devoured Sinclair BASIC and then went on to write machine code on it. It became a general-purpose calculation and computing scratchpad for repetitive homework due to the ease of BASIC programming, and with my Maplin 8255 I/O port card I was able to use it in the way a modern tech-aware kid might use an Arduino.
The RC2014 Micro is well placed to fill all of those functions as a BASIC and machine code learning platform on which to get down to the hardware in a way you simply can’t on most modern computers, and though the Arduino represents a far more sensible choice for hardware interfacing there is also an RC2014 backplane and I/O board available for the Micro’s expansion bus should you wish to have a go. Will I use it for these things? It’s certainly much more convenient than its full-sized sibling, so it’s quite likely I’ll be getting my hands dirty with a little bit of Z80 code. It’s astounding how much you can forget in 35 years!
The RC2014 Micro can be bought from Spencer’s Tindie store, with substantial bulk discounts for those workshop customers. If you want the full retrocomputer experience it’s a good choice as it provides about as simple a way into Z80 hardware and software as possible. The cost of simplicity comes in having no non-volatile storage and in lacking the hardware to run CP/M, but it has to be borne in mind that it’s the bottom of the RC2014 range. For comparison you can read our review of the original RC2014, over which we’d say the chief advantage of the Micro is its relative ease of construction.
As the name implies, the OSEP STEM board is an embedded project board primarily aimed at education. You use jumper wires to connect components and a visual block coding language to make it go.
I have fond memories of kits from companies like Radio Shack that had dozens of parts on a board, with spring terminals to connect them with jumper wires. Advertised with clickbait titles like “200 in 1”, you’d get a book showing how to wire the parts to make a radio, or an alarm, or a light blinker, or whatever.
The STEM Kit 1 is sort of a modern arduino-powered version of these kits. The board hosts a stand-alone Arduino UNO clone (included with the kit) and also has a host of things you might want to hook to it. Things like the speakers and stepper motors have drivers on board so you can easily drive them from the arduino. You get a bunch of jumper wires to make the connections, too. Most things that need to be connected to something permanently (like ground) are prewired on the PCB. The other connections use a single pin. You can see this arrangement with the three rotary pots which have a single pin next to the label (“POT1”, etc.).
I’m a sucker for a sale, so when I saw a local store had OSEPP’s STEM board for about $30, I had to pick one up. The suggested price for these boards is $150, but most of the time I see them listed for about $100. At the deeply discounted price I couldn’t resist checking it out.
So does an embedded many-in-one project kit like this one live up to that legacy? I spent some time with the board. Bottom line, if you can find a deal on the price I think it’s worth it. At full price, perhaps not. Join me after the break as I walk through what the OSEPP has to offer.
If there is one thing that most Hackaday readers will know about Denmark, it is that it’s the home of the Lego brick. The toy first appeared at the end of the 1940s from the factory of Ole Kirk Christiansen‘s Lego company in Billund, central Denmark, and has remained inseparable from both the town and the country ever since.
When spending a week in Denmark for the BornHack hacker camp it made absolute sense to take a day out to drive up to Billund and visit the famous Legoland theme park. All those childhood dreams of seeing the fabled attraction would be satisfied, making the visit a day to remember.
The Danes at Bornhack however had other ideas. By all means go to Legoland they said, but also take in Lego House. As a Brit I’d never heard of it, so was quickly educated. It seems that while Legoland is a kid’s theme park, Lego House is a far more Lego-brick-focused experience, and in the view of the Danish hackers, much better.
Paul Stoffregen did it again: the Teensy 4.0 has been released. The latest in the Teensy microcontroller development board line, the 4.0 returns to the smaller form-factor last seen with the 3.2, as opposed to the larger 3.5 and 3.6 boards.
Don’t let the smaller size fool you; the 4.0 is based on an ARM Cortex M7 running at 600 MHz (!), the fastest microcontroller you can get in 2019, and testing on real-world examples shows it executing code more than five times faster than the Teensy 3.6, and fifteen times faster than the Teensy 3.2. Of course, the new board is also packed with periperals, including two 480 Mbps USB ports, 3 digital audio interfaces, 3 CAN busses, and multiple SPI/I2C/serial interfaces backed with integrated FIFOs. Programming? Easy: there’s an add-on to the Arduino IDE called Teensyduino that “just works”. And it rings up at an MSRP of just $19.95; a welcomed price point, but not unexpected for a microcontroller breakout board.
The board launches today, but I had a chance to test drive a couple of them in one of the East Coast Hackaday labs over the past few days. So, let’s have a closer look.