New Product: The Raspberry Pi Debug Probe

February 21, 2023 by Jenny List 35 Comments

It’s fair to say that among the new product launches we see all the time, anything new from the folks at Raspberry Pi claims our attention. It’s not that their signature Linux single-board computers (SBCs) are necessarily the best or the fastest hardware on paper, but that they’re the ones with meaningful decade-plus support. Add to that their RP2040 microcontroller and its associated Pico boards, and they’re the one to watch.

Today we’ve got news of a new Pi, not a general purpose computer, but useful nevertheless. The Raspberry Pi Debug Probe is a small RP2040-based board that provides a SWD interface for debugging any ARM microcontroller as well as a more generic USB to UART interface.

The article sums up nicely what this board does — it’s for bare metal ARM coders, and it uses ARM’s built-in debugging infrastructure. It’s something that away from Hackaday we’ve seen friends using the 2040 for as one of the few readily available chips in the shortage, and it’s thus extremely convenient to have readily available as a product.

So if you’re a high level programmer it’s not essential, but if you’re really getting down to the nuts-and-bolts of an ARM microcontroller then you’ll want one of these. Of course, it’s by no means the first SWD interface we’ve seen, here’s one using an ESP32.

Exploring The History Of EPROM In The Soviet Union

February 21, 2023 by Chris Lott 17 Comments

An article on the history of EPROMs in the Soviet Union by [Vladimir Yakovlev] over at The CPU Shack Museum caught our attention. It is part one of a series on the topic, and walks you through the earliest Soviet EPROMs families.

Early EPROM programmer using punched paper tape (Intel, Electronics Magazine 1971)

The first of which, from the 1970s, is the K505RR1 developed and manufactured in Kyiv, equivalent to the first-generation Intel 1702A. It could hold 2048 bits, organized as 256×8, and offered a whopping 20 reprogramming cycles and data retention of 5000 hours.

The narrative proceeds to introduce several subsequent generations, design facilities, manufacturing techniques, and representative chip examples. A few tidbits — unlike Western EPROMs, the Soviets managed to put quartz windows in plastic packages (see the KP573 family).

In addition to the common gray or white, they also used different terracotta colored ceramic packages. An odd ceramic flat-pack EPROM is shown, and also some EPROMs whose dies have been painted over and re-badged as OTP chips.

Intel began producing EPROMs in 1971 as reported by the inventor, Intel’s Dov Frohman-Bentchkowsky, in Electronics Magazine’s 10 May edition (pg 91). We learned, amongst other things, that the 1701 did not have a quartz window, but could still be erased by exposure to X-rays. A friendly word of warning — browsing electronics advertisements from 50 years ago can easily consume your entire morning.

Once the package is sealed, information can still be erased by exposing it to X radiation in excess of 5×10⁴ rads, a dose which is easily attainable with commercial X-ray generators.

To dig deeper, check out the CPU Shack’s write-up on the history of EPROMs in general, and a piece we wrote in 2014 about the history of home computers behind the Iron Curtain.

Tidy Breadboard Uses Banana Bread

February 20, 2023 by Chris Lott 21 Comments

Self-described passionate maker in the electronics and 3D printing world, [Jakob], aka [testudor], was getting frustrated trying to connect banana plugs to solderless breadboards. Project Banana Bread was born — small banana jack adaptors and a companion tray with pockets to hold up to six modules.

The base in the photo is made from 5083 aluminum, machined on a homemade CNC router. But design files for a yet-to-be-tested 3D printer version are available as well. As can happen, he strayed from the original goal of solving the banana jack issue, and also cranked out a USB-serial port and a blank template module for any custom interfaces folks may want to implement.

If it is only power connections you are interested in, we covered the Open Power project back in 2019. And also don’t forget the mother of all breadboards, this 1960s behemoth we wrote about last year. What kinds of breadboard interface modules do you find most useful? Let us know in the comments below.

Digital Library Of Amateur Radio And Communications Is A Treasure Trove

February 20, 2023 by Al Williams 24 Comments

Having a big bookshelf of ham radio books and magazines used to be a point of bragging right for hams. These days, you are more likely to just browse the internet for information. But you can still have, virtually, that big shelf of old ham books, thanks to the DLARC — the digital library of Amateur Radio and Communications.

A grant from a private foundation has enable the Internet Archive to scan and index a trove of ham radio publications, including the old Callbooks, 73 Magazine, several ham radio group’s newsletters from around the globe, Radio Craft, and manuals from Icom, Kenwood, Yaesu, and others.

Continue reading “Digital Library Of Amateur Radio And Communications Is A Treasure Trove” →

Clear PLA Diffuses LEDs

February 20, 2023 by Al Williams 11 Comments

[Chuck] often prints up interesting 3D prints. But we enjoyed his enhancement to a cheap LED Christmas tree kit. The original kit was simply a few green PCBs in the shape of a tree. Cute, but not really something a non-nerd would appreciate. What [Chuck] did, though, is printed a clear PLA overcoat for it and it came out great. You can see how great in the video below.

You might think transparent PLA would be really clear, but because of the layers, it is more translucent than transparent. For an LED diffuser, though, it works great. There are a few things to consider when printing for this purpose. First, you’d think vase mode would be perfect for this, but he found out it didn’t work well — possibly due to something in the model, which was a download from Thingiverse.

Continue reading “Clear PLA Diffuses LEDs” →

Automating The Most Analog Of HVAC Equipment

February 20, 2023 by Bryan Cockfield 35 Comments

Burning wood, while not a perfect heating solution, has a number of advantages over more modern heating appliances. It’s a renewable resource, doesn’t add carbon to the atmosphere over geologic time scales like fossil fuels do, can be harvested locally using simple tools, and it doesn’t require any modern infrastructure to support it. That being said, wood stoves aren’t something that are very high-tech and don’t lend themselves particularly well to automation as a result, at least with the exception of this wood stove from [jotulf45v2].

While this doesn’t automate the loading or direct control of a modern pellet stove, it does help [jotulf45v2] know when the best times are for loading more wood into the stove and helps keep the stove in the right temperature range to avoid the dangerous formation of creosote on the inside of his chimney caused by low temperature burns. Two temperature sensors, one on the stovetop and the other on the stove pipe, monitor the stove exhaust temperature. They feed data to a Node-RED system running on a Raspberry Pi which automatically notifies the user by text message when certain stove temperatures are reached.

For anyone heating with wood, tools like this are indispensable to help avoid spending an otherwise unnecessary amount of time getting a fire up to temperature quickly without over-firing the stove. Modern pellet stoves have some more modern conveniences like this built in, but many of the perks of using cord wood are lost with these devices. There are plenty of other ways to heat with wood too; take a look at this custom wood boiler which serves as a hot water heater.

Low Power Challenge: Weather Station Runs For Months Thanks To E-Ink Display

February 20, 2023 by Robin Kearey 1 Comment

Having a device in your living room that shows weather information is convenient, and building one of those is a great project if you enjoy tinkering with microcontrollers and environmental sensors. It’s also a great way to learn about low-power design, as [x-labz] demonstrated with their e-ink weather station which works for no less than 60 days on a single battery charge. It has a clear display that shows the local temperature and humidity, as well as the weather forecast for the day.

The display is a 4.2″ e-paper module with a resolution of 400 x 300 pixels. It uses just 26 mW of power for a few seconds while it updates its image, and basically zero watts when showing a static picture. It’s driven by a tiny ESP32C3 processor board, which downloads the weather forecast from weatherapi.com every two hours. The indoor climate is measured by an SHT-21 temperature and humidity sensor mounted behind the display, while the outdoor data is gathered by a WiFi-connected sensor installed on [x-labz]’s balcony.

The key to achieving low power usage here is to keep the ESP32 in sleep mode as much as possible. The CPU briefly wakes up once every five minutes to read out the indoor sensor and once every fifteen minutes to gather data from outside, using the relatively power-hungry WiFi module.

To further reduce power consumption, the CPU core is driven at the lowest possible clock speed at all times: 10 MHz when reading the indoor sensor, and 80 MHz when using the WiFi connection. All of this helps ensure that just one 600 mAh lithium battery can keep everything running for those 60 days.

E-ink displays are perfect for text and simple graphics that don’t change too often, which is why they’re very popular in weather stations. With a bit of tweaking though, LCDs can also be optimized for low power.