Logic Analyzers: Decoding And Monitoring

April 15, 2024 by 7 Comments

Last time, we looked into using a logic analyzer to decode SPI signals of LCD displays, which can help us reuse LCD screens from proprietary systems, or port LCD driver code from one platform to another! If you are to do that, however, you might find a bottleneck – typically, you need to capture a whole bunch of data and then go through it, comparing bytes one by one, which is quite slow. If you have tinkered with Pulseview, you probably have already found an option to export decoded data – all you need to do is right-click on the decoder output and you’ll be presented with a bunch of options to export it. Here’s what you will find:

2521888-2521888 I²C: Address/data: Start
2521896-2521947 I²C: Address/data: Address write: 22
2521947-2521954 I²C: Address/data: Write
2521955-2521962 I²C: Address/data: ACK
2521962-2522020 I²C: Address/data: Data write: 01
2522021-2522028 I²C: Address/data: ACK
2522030-2522030 I²C: Address/data: Start repeat
2522038-2522089 I²C: Address/data: Address read: 22
2522089-2522096 I²C: Address/data: Read
2522096-2522103 I²C: Address/data: ACK
2522104-2522162 I²C: Address/data: Data read: 91
2522162-2522169 I²C: Address/data: NACK
2522172-2522172 I²C: Address/data: Stop

Whether on the screen or in an exported file, the decoder output is not terribly readable – depending on the kind of interface you’re sniffing, be it I2C, UART or SPI, you will get five to ten lines of decoder output for every byte transferred. If you’re getting large amounts of data from your logic analyzer and you want to actually understand what’s happening, this quickly will become a problem – not to mention that scrolling through the Pulseview window is not a comfortable experience.

The above output could look like this: 0x22: read 0x01 ( DEV_ID) = 0x91 (0b10010001). Yet, it doesn’t, and I want to show you how to correct this injustice. Today, we supercharge Pulseview with a few external scripts, and I’ll show you how to transfer large amounts of Sigrok decoder output data into beautiful human-readable transaction printouts. While we’re at it, let’s also check out commandline sigrok, avoiding the Pulseview UI altogether – with sigrok-cli, you can easily create a lightweight program that runs in the background and saves all captured data into a text file, or shows it on a screen in realtime! Continue reading “Logic Analyzers: Decoding And Monitoring” →

Analyzing The Code From The Terminator’s HUD

April 15, 2024 by 35 Comments

The T-800, also known as the Terminator, was like some kind of non-giving up robot guy. The robot assassin viewed the world through a tinted view with lines of code scrolling by all the while. It was cinematic shorthand to tell the audience they were looking through the eyes of a machine. Now, a YouTuber called [Open Source] has analyzed that code.

The video highlights one interesting finds, concerning graphics seen in the T-800’s vision. They appear to match the output of various code listings and articles in Nibble Magazine, specifically its September 1984 issue. One example spotted was a compass rose, spawned from an Apple Basic listing. it was a basic quiz to help teach children to understand the compass. Another graphic appears to be cribbed from the same issue in the MacPaint Patterns section.

The weird thing is that the original film came out in October 1984 — just a month after that article would have hit the news stands. It suggests perhaps someone involved with the movie was also involved or had access to an early copy of Nibble Magazine — or that the examples in the magazine were just rehashed from some other earlier source.

Code that regularly flickers in the left of the T-800s vision is just 6502 machine code. It’s apparently just a random hexdump from an Apple II’s memory. At other times, there’s also 6502 assembly code on screen which includes various programmer comments still intact. There’s even some code cribbed from the Apple II DOS 3.3 RAM Disk driver.

It’s neat to see someone actually track down the background of these classic graphics. Hacking and computers are usually portrayed in a fairly unrealistic way in movies, and it’s no different in The Terminator (1984). Still, that doesn’t mean the movies aren’t fun!

Continue reading “Analyzing The Code From The Terminator’s HUD” →

Remembering Peter Higgs And The Gravity Of His Contributions To Physics

April 15, 2024 by 8 Comments

There are probably very few people on this globe who at some point in time haven’t heard the term ‘Higgs Boson’  zip past, along with the term ‘God Particle’. As during the 2010s the scientists at CERN were trying to find evidence for the existence of this scalar boson and with it evidence for the existence of the Higgs field that according to the Standard Model gives mass to gauge bosons like photons, this effort got communicated in the international media and elsewhere in a variety of ways.

Along with this media frenzy, the physicist after whom the Higgs boson was named also gained more fame, despite Peter Higgs already having been a well-known presence in the scientific community for decades by that time until his retirement in 1996. With Peter Higgs’ recent death after a brief illness at the age of 94, we are saying farewell to one of the big names in physics. Even if not a household name like Einstein and Stephen Hawking, the photogenic hunt for the Higgs boson ended up highlighting a story that began in the 1960s with a series of papers.

Continue reading “Remembering Peter Higgs And The Gravity Of His Contributions To Physics” →

How Do You Make A Repairable E-Reader

April 15, 2024 by 38 Comments

Mobile devices have become notorious for their unrepairability, with glued-together parts and impossible-to-reach connectors. So it’s refreshing to see something new in that field from the e-book reader brand Kobo in the form of a partnership with iFixit to ensure that their new reader line can be fixed.

Naturally, we welcome any such move, not least because it disproves the notion that portable devices are impossible to make with repairability in mind. However, the linked article is especially interesting because it includes a picture of a reader, and its cover has been removed. We’re unsure whether or not this is one of the new ones, but it’s still worth looking at it with reparability eyes. Just what have they done to make it easier to repair?

Continue reading “How Do You Make A Repairable E-Reader” →

Waveform Generator Teardown Is Nearly Empty

April 15, 2024 by 24 Comments

We always enjoy [Kerry Wong’s] insightful teardowns, and recently, he opened up a UTG1042X arbitrary waveform generator. Getting inside was a bit of a challenge since there were no visible screws. Turns out, they were under some stickers. We always dislike that because it is very difficult to get the unit to go back together.

Once open, the case reveals it is almost completely empty. The back panel has a power supply, and the front panel has all the working circuitry. The box seems to be for holding the foot and preventing the device from getting lost on your bench.

Continue reading “Waveform Generator Teardown Is Nearly Empty” →

Laser cut bug body with pincers and electronics to control the pincers

A Buggy Entry In The Useless Robot Category

April 14, 2024 by 1 Comment

No one loves a useless robot more than we do here at Hackaday. But if anyone does it might be [ARC385] with her Bug Bite Bot.

A true engineering marvel, [ARC385]’s bug bot extinguishes the candle on its own little birthday cupcake. Yup. That’s it! Even more peculiar, (and to be fair, somewhat fittingly) before her bug releases its less-than-crushing bite, it plays itself a little Happy Birthday jingle. Seems legit.

If you choose to build this little bug yourself, you’ll be happy to know that the electronics on this build are pretty straightforward. Servo motors control the pincers and a photoresistor detects the flame. [ARC385] tried using a flame sensor instead of the photoresistor, but mentioned she couldn’t get consistent performance at her required sensing distance. She also mentions that you’ll probably need to calibrate the photoresistor to ambient light if for whatever reason you choose to embark on this build yourself.

[ARC385] did a pretty good job with the laser-cut plywood to construct the bug, but using plywood adds a few more question marks to this already puzzling build. She even mentioned having to modify the pincers so they wouldn’t catch fire trying to extinguish the candle.

Would be cool if the candle could rekindle itself, but we can’t possibly support making this hack even more of a fire hazard than it already is.

Continue reading “A Buggy Entry In The Useless Robot Category” →

Voice Control For A Vintage Heathkit Radio

April 14, 2024 by 6 Comments

Most modern ham rigs have a voice activated transmission (VOX) mode, although we don’t know many people who use it often. When a transmitter is in VOX mode, it starts transmitting when you talk, and then, when you pause for a second or two, the transmitter turns off. Many old ham transmitters, though, didn’t support VOX, so Heathkit sold the VX-1 “electronic voice control” to add VOX to older transmitters. [Jeff Tranter] shows us inside a clean-looking unit.

These devices were sold from 1958 to 1960 and used tubes and a selenium rectifier. The device is connected between the microphone and the transmitter. It also sat between the receiver and the speaker to mute audio while transmitting. The original unit had a screw terminal to connect to the outside world, and some of the screws had live line voltage on them. The unit [Jeff] examines is modified to have phono jacks along with a few other repairs.

The wiring looks like a tube radio. Tubes are above the chassis, and point-to-point wiring is underneath. There is also an unusual sealed selenium rectifier. [Jeff] shows how the device works using just a receiver. A few minor repairs were needed.

If you are interested in getting your ham license, most modern radios support VOX out of the box — no rhyme intended. We do, however, love that old Heathkit gear.

Continue reading “Voice Control For A Vintage Heathkit Radio” →