TVout Library Brings Cardboard Arcade To Life

August 12, 2022 by 12 Comments

Recycling old CRTs is a true Hackaday tradition, and [Rob’s] mini arcade is sure to grab your attention.

First of all, you’ll probably appreciate [Rob] circumventing the supply shortage by getting all his components from recycled material. That’s probably the only way to get anything these days. He salvaged a small CRT from an old-school video intercom system and snagged the buttons, speakers, and switches from other unused devices laying around. Not all is lost, however, as [Rob] was able to purchase an Arduino Nano and a few resistors online. So maybe things are turning around in that category, who knows?

You’ll probably also appreciate how remarkably simple this hack is. No need for a Raspberry Pi as your standard 8-bit microcontroller will do the trick. And, fortunately, [Rob] found a nice library to help him generate the composite video signal, doing most of the work for him. All that was left to do was to build the arcade cabinet. Recreating the classic design was a pretty easy step, but you might opt for something a little nicer than cardboard though. But, hey, if it does the trick, then why not?

Cool project, [Rob]! We’re definitely happy to add this project to our retro collection here at Hackaday.

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MythTV Library On Apple TV Without A Jailbreak

August 2, 2012 by 16 Comments

[Dan] wrote in to share a link to his MythTv to Apple TV setup. He found a way to make the recordings he made on his Linux box available on the 2nd Generation Apple TV. Our first thought is that he would use XBMC on a jailbroken device  but that is not the case. The secret is to roll iTunes into the mix.

Take a look at the diagram above. The system starts with an Arch Linux box that runs MythTV, an open source program which allows you to record from tuner or encoder hardware. But actually watching those recordings on an iOS device is difficult for a couple of reasons. First, Apple likes to keep their devices locked up tight in hopes that you buy your entertainment rather than watching over-the-air records. Second, if you’re recording ATSC channels the files may be 1080i or 1080p, neither of which can be handled by the Apple TV 2. [Dan] gets around this by first using the command line version of Handbrake to transcode the recordings to an h264 format. He then uses iTunes running on an Windows 7 virtual machine (on the Linux box) to host the transcoded files in a library the Apple TV can access.

Bust Out That Old Analog Scope For Some Velociraster Fun!

April 17, 2023 by 6 Comments

[Oli Wright] is back again with another installation of CRT shenanigans. This time, the target is the humble analog oscilloscope, specifically a Farnell DTV12-14 12 MHz dual-channel unit, which features a handy X-Y mode. The result is the Velociraster, a simple (in hardware terms) Raspberry Pi Pico based display driver.

Using a Pico to drive a pair of AD767 12-bit DACs, the outputs of which drive the two ‘scope input channels directly, this breadboard and pile-of-wires hack can produce some seriously impressive results. On the software side of things, the design is a now a familiar show, with core0 running the application’s high-level processing, and core1 acting in parallel as the rendering engine, determining static DAC codes to be pushed out to the DACs using the DMA and the PIO.

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All About USB-C: Resistors And Emarkers

January 4, 2023 by 16 Comments

If you’ve been following along our USB-C saga, you know that the CC wire in the USB-C cables is used for communications and polarity detection. However, what’s not as widely known is that there are two protocols used in USB-C for communications – an analog one and a digital one. Today, let’s look at the analog signalling used in USB-C – in part, learn more about the fabled 5.1 kΩ resistors and how they work. We’ll also learn about emarkers and the mysterious entity that is VCONN!

USB-C power supply expects to sense a certain value pulldown on the CC line before it provides 5 V on VBUS, and any higher voltages have to be negotiated digitally. The PSU, be it your laptop’s port or a charger, can detect the pulldown (known as Rd) because it keeps a pullup (known as Rp) on the CC line – it then checks if a voltage divider has formed on CC, and whether the resulting voltage is within acceptable range.

If you plug a device that doesn’t make a pulldown accessible through the CC wire in the cable, your device will never get power from a USB-C port, and would only work with a USB-A to USB-C cable. Even the smarter devices that can talk the digital part of USB-C are expected to have pulldowns, it’s just that those pulldowns are internal to the USB-C communication IC used. A USB-C port that wants to receive power needs to have a pulldown.

This part is well-known by now, but we’ve seen lack-of-resistor failures in cheap devices aplenty, and the colloquial advice is “add 5.1 kΩ resistors”. You might be afraid to think it’s so simple, but you’d be surprised. Continue reading “All About USB-C: Resistors And Emarkers” →

This Week In Security: Adblock For Security, ProxyNotShell Lives, And CVSS 10 To Not Worry About

December 30, 2022 by 14 Comments

The ubiquity of ransomware continues, this time with The Guardian announcing they were partially shut down from an attack. Staff are working from home as the incident is being investigated and data is recovered. Publishing seems to be continuing, and the print paper ran as expected.

There have been a couple reports published recently on how ransomware and other malware is distributed, the first being a public service announcement from the FBI, detailing what might be a blindly obvious attack vector — search engine advertising. A bad actor picks a company or common search term, pays for placement on a search engine, and then builds a fake web site that looks legitimate. For bonus points, this uses a typosquatted domain, like adobe[dot]cm or a punycode domain that looks even closer to the real thing.

The FBI has a trio of recommendations, one of which I whole-heartedly agree with. Their first suggestion is to inspect links before clicking them, which is great, except for the punycode attack. In fact, there are enough lookalike glyphs to make this essentially useless. Second is to type in URLs directly rather than using a search engine to find a company’s site. This is great so long as you know the URL and don’t make a typo. But honestly, haven’t we all accidentally ended up at website[dot]co by doing this? Their last recommendation is the good one, and that is to run a high-quality ad-blocker for security. Just remember to selectively disable blocking for websites you want to support. (Like Hackaday!) Continue reading “This Week In Security: Adblock For Security, ProxyNotShell Lives, And CVSS 10 To Not Worry About” →

TV Repair By Mail

November 17, 2022 by 49 Comments

I don’t think there was ever a correspondence school called the “Close Cover Before Striking School” but since book matches — which used to be a thing when most people smoked — always had that text on them anyway perhaps there should have been. There was a time when electronic magazines, billboards, and even book matches were constantly bombarding us with ads to have a career in electronics. Or computers. Or TV repair. So while we think of distance learning as a new idea, really it is just the evolution of these old correspondence schools which date back quite some time.

How far exactly? Hard to say. There’s evidence of some distance learning going back as far as 1728. In 1837, there was a correspondence course to learn shorthand. By 1858, the University of London started its external program for correspondence work and the University of Chicago had a home study division in 1892.  Radio was an early choice of topic, too. In the United States, the United Wireless Telegraph company started a training school — later the Marconi Institute — in 1909. However, it is doubtful that there was any correspondence training going on there until much later.

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The Pi Pico board on top of a white box with an Ethernet jack, with a sensor module plugged onto the Pico's pin headers. A black MicroUSB and a green Ethernet cable are connected to this device.

An Elegant Ethernet Library For Your Next RP2040 Project

August 27, 2022 by 17 Comments

A few days ago we covered a project that brought Ethernet connectivity to the Raspberry Pi Pico using little more than some twisted pair and a RJ-45 connector. It was a neat trick, but not exactly ready for widespread adoption. Looking to improve on things a bit, [tvlad1234] has taken that project’s code and rewritten it into a friendly library you can use with any RP2040 board.

In case you missed it, the initial demo did 10BASE-T transmission by bit-banging with the PIO, and was able to send UDP messages to devices on the wired LAN. It was an impressive accomplishment, but its code didn’t make it easy to build your project around it. This new library makes UDP messaging as easy as a printf, offloading all non-PIO-managed Ethernet signal work onto the RP2040’s second CPU core. The library even generates a random MAC address out of your flash chip’s serial number!

As a demonstration of the new library, [tvlad1234] has put together a simple Ethernet-connected temperature monitor using the BMP085 or BMP180 sensor connect over I2C. If you feel like you could use an Ethernet transmit-only sensor in your life, browsing the source code would be a great start.