Parts

712 Articles

Espressif Leaks ESP32-C3: A WiFi SoC That’s RISC-V And Is ESP8266 Pin-Compatible

November 22, 2020 by 56 Comments

Six years on from the emergence of the Espressif ESP8266 we might believe that the focus had shifted to the newer dual-core ESP32. But here comes a twist in the form of the newly-revealed ESP32-C3. It’s a WiFi SoC that despite its ESP32 name contains a RISC-V core in place of the Tensilica core in the ESP32s we know, and uses the ESP8266 pin-out rather than that of its newer sibling. There’s relatively little information about it at the time of writing, but CNX Software have gathered together what there is including a draft datasheet whose English translation is available as a Mega download. As with other ESP32 family members, this one delivers b/g/n WiFi and Bluetooth Low-Energy (BLE) 5, where it differs is the RISC-V 32 Single-core processor with a clock speed of up to 160 MHz. There is 400 kB of SRAM and 384 kB ROM storage space built in.

While there is no official announcement yet, Espressif has been dropping hints. There’s been an OpenOCD configuration file for it in the Espressif repositories since the end of last month. And on Friday, Espressif Software Engineering Manager [Sprite_tm] answered a reddit comment, confirming the RISC-V core.

ESP-01: Kjerish, CC BY-SA 4.0, RISC-V logo: RISC-V foundation, Public domain.

Why they are releasing the part as an ESP32 rather than giving it a series number of its own remains a mystery, but it’s not hard to see why it makes commercial sense to create it in an ESP8266-compatible footprint. The arrival of competing parts in the cheap wireless SoC space such as the Bouffalo Labs BL602 we mentioned recently is likely to be eating into sales of the six-year-old chip, so an upgrade path to a more capable part with minimal new hardware design requirements could be a powerful incentive for large customers to stay with Espressif.

We’re left to guess on how exactly the rollout will proceed. We expect to see similar developer support to that they now provide for their other chips, and then ESP32-C3 powered versions of existing ESP8266 boards in short order. It’s also to be hoped that a standard RISC-V toolchain could be used instead of the device-specific ones for current Espressif offerings. What we should not expect are open-source replacements for the blobs that drive the on-board peripherals, as the new chip will share the same closed-source IP as its predecessors for them. Perhaps if the PINE64 initiative to reverse engineer blobs for the BL602 bears fruit, we might see a similar effort for this chip.

Intel’s Forgotten 1970s Dual Core Processor

November 22, 2020 by 56 Comments

Can you remember when you received your first computer or device containing a CPU with more than one main processing core on the die? We’re guessing for many of you it was probably some time around 2005, and it’s likely that processor would have been in the Intel Core Duo family of chips. With a dual-core ESP32 now costing relative pennies it may be difficult to grasp in 2020, but there was a time when a multi-core processor was a very big deal indeed.

What if we were to tell you that there was another Intel dual-core processor back in the 1970s, and that some of you may even have owned one without ever realizing it? It’s a tale related to us by [Chris Evans], about how a team of reverse engineering enthusiasts came together to unlock the secrets of the Intel 8271.

If you’ve never heard of the 8271 you can be forgiven, for far from being part of the chip giant’s processor line it was instead a high-performance floppy disk controller that appeared in relatively few machines. An unexpected use of it came in the Acorn BBC Micro which is where [Chris] first encountered it. There’s very little documentation of its internal features, so an impressive combination of decapping and research was needed by the team before they could understand its secrets.

As you will no doubt have guessed, what they found is no general purpose application processor but a mask-programmed dual-core microcontroller optimized for data throughput and containing substantial programmable logic arrays (PLAs). It’s a relatively large chip for its day, and with 22,000 transistors it dwarfs the relatively svelte 6502 that does the BBC Micro’s heavy lifting. Some very hard work at decoding the RMO and PLAs arrives at the conclusion that the main core has some similarity to their 8048 architecture, and the dual-core design is revealed as a solution to the problem of calculating cyclic redundancy checks on the fly at disk transfer speed. There is even another chip using the same silicon in the contemporary Intel range, the 8273 synchronous data link controller simply has a different ROM. All in all the article provides a fascinating insight into this very unusual corner of 1970s microcomputer technology.

As long-time readers will know, we have an interest in chip reverse engineering.

High-Speed Spectrometer Built With Cheap Linear CCD

November 21, 2020 by 37 Comments

If you’ve ever dreamed of building a proper spectrometer, it looks like the ESPROS epc901 CCD sensor is absolutely worth your attention. It’s fast, sensitive, easy to interface with, and at just $24 USD, it won’t break the bank. There’s only one problem: implementing it in your project means either working with the bare 2×16 0.5 mm pitch BGA device, or shelling out nearly $1,400 USD for the development kit.

Thankfully, [Adrian Studer] has come up with a compromise. While you’ll still need to reflow the BGA to get it mounted, his open hardware breakout and adapter boards for the ESPROS epc901 make the sensor far easier to work with.

It’s not just a hardware solution either, he also provides firmware code for the STM32L4 based Nucleo development board and some Python scripts that make it easy to pull data from the sensor. The firmware even includes a simple command line interface to control the hardware that you can access over serial.

With the sensor successfully wrangled, [Adrian] partnered with [Frank Milburn] to build an affordable spectrometer around it. The design makes use of a 3D printed chamber, a simple commercial diffraction grating, and an array of entrance slits ranging from 0.5 to 0.0254 millimeters in width that were laser-cut into a sheet of stainless steel.

In the videos after the break, you can see the finished spectrometer being used to determine the wavelength of LEDs, as well as a demonstration of how the high-speed camera module is able to study the spectral variations of a CFL bulb over time. [Adrian] tells us that he and [Frank] are open to suggestions as to what they should point their new spectrometer at next, so let them know in the comments if you’ve got any interesting ideas.

We’ve seen an incredible number of spectrometer builds over the years, and some of the more recent ones are really pushing the envelope in terms of what the DIY scientist is capable of doing in the home lab. While they’re still fairly niche, these instruments are slowly but surely finding their way into the hands of more curious hackers.

Continue reading “High-Speed Spectrometer Built With Cheap Linear CCD” →

New Part Day: Bouffalo Labs BL602 RISC-V Wi-Fi/Bluetooth SoC

November 20, 2020 by 20 Comments

We should all by now be used to microcontrollers with wireless hardware on board, with Espressif or Nordic Labs dominating the hacker scene. There have been several other contenders in this arena over the years that haven’t really caught the attention of our community, usually because of the opacity of their available information.

A new contender should be worth a second look though. The BL602 from Bouffalo Labs is a Wi-Fi- and Bluetooth LE-capable microcontroller with a 32-bit RISC-V derived core. If that doesn’t interest you much, perhaps news that the PINE64 folks are spearheading an effort to reverse engineer it for a fully open-source blob-free wireless implementation might sharpen your attention.

So where can you get your hands on one? Hold your horses, this chip is at an early stage in its gestation. We can see that there are some exciting possibilities in store, but we’re still figuring out the hardware interfaces and other software required to make it work. A community is hard at work reverse engineering it, which leads us back to the PINE64 story we mentioned earlier.

You can find BL602 modules from AliExpress vendors, but the PINE64 folks will offer you a free one if you join their blob reverse engineering effort. Take note though, this offer is for those prepared to show commitment to the project, so don’t spam them in the hope of free stuff if you won’t be helping deliver the goods.

We might see the BL602 gaining an open-source toolchain and internal blobs over the coming months thanks to the efforts of those working on it. Just as the ESP8266 did back in 2014, it’s starting as a black box with a relative scarcity of information. But if this hacking effort pays off, we’ll have a cheap RISC-V Wi-Fi and Bluetooth module with entirely open-source software from the silicon upwards. What a time to be alive!

Thanks [Renze] for the tip.

E-Paper Weather Display Is A Great Base To Build From

November 3, 2020 by 26 Comments

As e-paper modules have become more affordable, we’ve started to see them pop up more and more in hacker projects. It used to be that you had to force a second-hand Kindle to do your bidding, but now you can buy just the screen itself complete with a header to plug right into your Raspberry Pi. It will still cost you as much as a used Kindle…but at least it comes with some documentation and there are Python libraries to talk to it.

But where to start? If you need some inspiration, and perhaps a little source code, this very slick weather display put together by [James Howard] is a great as baseline. Not that it really needs any additional refinement, as we think it already looks gorgeous. But rather than starting from scratch for your own project, it would be much easier to graft some additional functionality onto his code.

A lot of that has to do with how concise and well commented his code is. We’ve seen enough of these projects to know the kind of spaghetti that’s often running on the backend, but there’s none of that here. [James] assembles the display using the powerful Pillow graphics library, which lets you draw primitives and drop in text and icons with just a couple lines of code.

Once all the data is plugged in, the entire screen is saved as an image file which is then opened up on the e-paper display. Even if you aren’t a Python expert, you should be able to understand what’s happening and how to bend it to your will.

We’ve always had high hopes for electronic paper, and it seems the technology might finally be hitting critical mass. While it’s still a bit expensive, we’ve started seeing it pop up in unexpected places to great effect. Hopefully projects like this one will inspire others to take the B&W plunge.

Bringing High Temperature 3D Printing To The Masses

October 28, 2020 by 77 Comments

Despite the impressive variety of thermoplastics that can be printed on consumer-level desktop 3D printers, the most commonly used filament is polylactic acid (PLA). That’s because it’s not only the cheapest material available, but also the easiest to work with. PLA can be extruded at temperatures as low as 180 °C, and it’s possible to get good results even without a heated bed. The downside is that objects printed in PLA tend to be somewhat brittle and have a low heat tolerance. It’s a fine plastic for prototyping and light duty projects, but it won’t take long for many users to outgrow its capabilities.

The next step up is usually polyethylene terephthalate glycol (PETG). This material isn’t much more difficult to work with than PLA, but is more durable, can handle higher temperatures, and in general is better suited for mechanical parts. If you need greater durability or higher heat tolerance than PETG offers, you could move on to something like acrylonitrile butadiene styrene (ABS), polycarbonate (PC), or nylon. But this is where things start to get tricky. Not only are the extrusion temperatures of these materials greater than 250 °C, but an enclosed print chamber is generally recommended for best results. That puts them on the upper end of what the hobbyist community is generally capable of working with.

Industrial 3D printers like the Apium P220 start at $30,000.

But high-end industrial 3D printers can use even stronger plastics such as polyetherimide (PEI) or members of the polyaryletherketone family (PAEK, PEEK, PEKK). Parts made from these materials are especially desirable for aerospace applications, as they can replace metal components while being substantially lighter.

These plastics must be extruded at temperatures approaching 400 °C, and a sealed build chamber kept at >100 °C for the duration of the print is an absolute necessity. The purchase price for a commercial printer with these capabilities is in the tens of thousands even on the low end, with some models priced well into the six figure range.

Of course there was a time, not quite so long ago, where the same could have been said of 3D printers in general. Machines that were once the sole domain of exceptionally well funded R&D labs now sit on the workbenches of hackers and makers all over the world. While it’s hard to say if we’ll see the same race to the bottom for high temperature 3D printers, the first steps towards democratizing the technology are already being made.

Continue reading “Bringing High Temperature 3D Printing To The Masses” →

What’s In A USB-C Connector?

October 27, 2020 by 30 Comments

Anyone who’s ever put together a bill-of-materials for an electronic device will be familiar with the process of scouring supplier catalogs and data sheets for the best choice of components. The trick is to score the best combination of price and performance for the final product, and for those unused to the process, there are always seemingly identical products with an astonishingly wide variety of prices. It’s a topic [Timon] explores in a Twitter thread, examining a 20-cent in quantity of 100 USB-C socket alongside one that costs only 5 cents, and his teardown provides a fascinating insight into their manufacture.

The parts look so nearly identical that while it’s possible to differentiate between them visually, it’s near impossible to work out which was the cheaper. Some tiny features such as a crack in a metal fold or a bit less plating on the contacts emerge, but even then it’s no guide to the quality as they don’t appear on the same part. It’s only when the metal shell is removed to expose the underlying plastic moulding that more clues emerge, as one moulding is more complex than the other. The more complex moulding provides a better and more reliable fit at the expense of a much more costly moulding process, so at last we can not only identify the more expensive part but also see where the extra cash has gone. It’s a subtle thing, but one that could make a huge difference to the performance of the final assembly and which makes for a fascinating expose for electronic design engineers.

If connectors are your thing, there’s a wealth of fascinating information in their history.