Endstops That Stay Out Of The Way

In the course of building a new delta printer, [thehans] decided he needed his own endstop design that used minimal hardware. Endstops are just switches that get hit when the printer moves at the extreme of an axis, but [thehans] wanted something with a bit of refinement for his BigDelta 3D Printer build.

The result is a small unit that cradles a microswitch and needs only a single zip tie that mounts flush, resulting in a super tidy looking piece. In addition, it mounts on the delta’s v-slot rails such that the mount does not take up any of the machine’s range of motion, because the carriage can travel past it. It is a parametric design made in OpenSCAD, so feel free to modify it to accommodate other types of switches.

Continue reading “Endstops That Stay Out Of The Way”

Sir, It Appears We’ve Been Jammed!

In a move that would induce ire in Lord Helmet, [Kedar Nimbalkar] has recreated Instructables user spacehun’s version of WiFi jammer that comes with a handful of features certain to frustrate whomever has provoked its wrath.

The jammer is an ESP8266 development board — running some additional custom code — accessed and controlled by a cell phone. From the interface, [Nimbalkar] is able to target a WiFi network and boot all the devices off the network by de-authenticating them. Another method is to flood the airspace with bogus SSIDs to make connecting to a valid network a drawn-out affair.

This kind of signal interruption is almost certainly illegal where you live. It does no permanent damage, but once again raises the existing deauth exploit and SSID loophole. [Nimbalkar]’s purpose in recreating this was for educational purposes and to highlight weaknesses in 802.11 WiFi protocols. The 802.11w standard should alleviate some of our fake deauth woes by using protected frames. Once the device authenticates on a network it will be able to detect fake deauth packets.

We featured a more targeted version of this hack that can be done using a PC — even targeting itself! And more recently there was a version that can target specific devices by jumping on the ACK.

Continue reading “Sir, It Appears We’ve Been Jammed!”

The Smallest Wave Blaster Card

In the early 90s, the Creative Sound Blaster was the soundcard. It wasn’t the absolute best sounding card on the market, but it quickly became the defacto standard and delivered good sound at the right price. It relied primarily on the Yamaha OPL-3 FM synthesis chip, but if you were feeling spendy, you could pimp it out with a Wave Blaster add-on card, which essentially bolted a sample synthesis engine onto the card. This gave the card a broad palette of sampled instruments with which to play MIDI tunes all the sweeter, so you could impress your grade school chums who came over to play DOOM.

It’s now 2017, if you hadn’t checked the calendar, and Sound Blasters from yesteryear are only going to go further upward in price. It goes without saying that add-on daughterboards and accessories are even rarer and are going to be priced accordingly. So, if you’re building a vintage gaming rig and are desperate for that sample-synth goodness, [Serdashop] are here to help with their latest offering, the Dreamblaster S2.

It’s reportedly the smallest Wave Blaster add-on board available, which is awesome. If you’re sticking it on top of your Sound Blaster 16, yes, it’s pointless – you’re not exactly short on room. But if you want to integrate this with a compact microcontroller project? Size matters. Yes, you can feed this thing MIDI signals and it’ll sing for you. A hot tip for the uninitiated: MIDI speaks serial, just like everything and everyone else. Your grandma learned to speak it in the war, you know.

Your options for hooking this up are either slotting it into a Wave Blaster compatible card, or buying the carrier board that allows you to use it with a Game Port, in addition to custom-wiring it to your own hardware. We’d love to see this as a HAT for the Raspberry Pi Zero. Do it, send it in and we’ll write it up.

We’ve seen [Serdashop]’s hardware here before – namely, the earlier Dreamblaster X2. Video below the break.

Continue reading “The Smallest Wave Blaster Card”

Lint For Shell Scripters

It used to be one of the joys of writing embedded software was never having to deploy shell scripts. But now with platforms like the Raspberry Pi becoming very common, Linux shell scripts can be a big part of a system–even the whole system, in some cases. How do you know your shell script is error-free before you deploy it? Of course, nothing can catch all errors, but you might try ShellCheck.

When you compile a C program, the compiler usually catches most of your gross errors. The shell, though, doesn’t look at everything until it runs which means you might have an error just waiting for the right path of an if statement or the wrong file name to occur. ShellCheck can help you identify those issues before deployment.

If you don’t like pasting your script into a Web page, you can install the checker locally by visiting GitHub. The readme file there also explains what kind of things the tool can catch. It can even integrate with common editors (as seen in the video below).

Continue reading “Lint For Shell Scripters”

Power Sipping Master Keeps Slave Clock On Time

Few things are as infuriating as clocks that are not synchronized. It’s frustrating when the clock on the range and the clock on the microwave act like they’re in time zones that are one minute apart. Now picture that same issue over dozens of clocks in a train station, or hundreds in a school or factory. It’s no wonder that slave clocks, which advance on signals from a master clock, were developed.

When a pair of vintage Lepaute slave clocks made their way to [melka], he knew just what to do – build his own master clock to keep the slave on track. This particularly stylish slave clock uses pulses of alternating polarity every 30 seconds and will work on 1.5-volt pulses, which let [melka] meet his design goal of running for a year off a single AA battery. To keep the power needs low, [melka] relies on the RTC to wake up the MSP430 every second to increment a counter. When it hits 30, a pulse is sent to the clock’s motor through an H-bridge; the MCU alternates the polarity of every other pulse to advance the clock.

It’s not immediately clear how the clock is set; we recall the slave clocks in high school rapidly advancing for Daylight Saving adjustments, so we assume [melka] has provided some way of pulsing the clock quickly to set the time. Regardless, it’s a good lesson in low-power design. And be sure to check out this PIC-based master clock replacement, too.

Save Big By Hacking Your Car Keys

Three hundred bucks for a new car key? Nonsense! When you lose your keys or want to have an extra made for that new teen driver, don’t let the stealership lighten your wallet. Just pull the ECU and hack some hex to add the new keys.

The video below is a whirlwind tour of the process [speedkar9] uses to reprogram Toyota ECUs to allow new keys to pass the security test on your new(er) car. Since the early 2000s or so, most manufacturers have included RFID chips in their keys so that only known keys will start a car. In Toyotas, this is done by an RFID reader in the steering column that passes the inserted key’s code to the engine control unit. If the 8-byte key code matches one of three values stored in the ECU, the car will start. Clearing the EEPROM in the ECU is the focus of [speedkar9]’s process, which connecting to the EEPROM and reading the contents. His rig includes an RS-232 serial connection, so the hardest part of this hack might be rounding up a PC with a DB-9 jack, but once you’ve got that covered, it’s just a little bit-bashing to “virginize” the ECU to ready it for reprogramming.

The details of the procedure will vary by manufacturer, of course, and cars of a more recent vintage will likely have even more security to worry about. Might you even run afoul of DRM like you would by hacking a tractor? Perhaps. But $300 is $300.

Continue reading “Save Big By Hacking Your Car Keys”

A Wallflower Jumps Into The Los Angeles Unconference

When I was asked to cover the Unconference in Los Angeles last week, I have to admit that I was a more than a little uncomfortable with the idea. I’m not big on traveling, and the idea of meeting a lot of folks was a little intimidating. Surely meeting Hackaday readers in person would be like walking into a real-life version of the comments section of a particularly controversial post. Right?

I couldn’t have been more wrong.

The LA Unconference, held at the Supplyframe Design Lab in Pasadena, was a far more collegial and engaging conference than any I’ve been to in my professional life. I couldn’t have asked for a better group to share the afternoon and evening with, and the quality of the talks was excellent. The Design Lab turned out to be a great space for the event — a large main room for the talks with plenty of little areas to break away for impromptu discussions and networking.

Continue reading “A Wallflower Jumps Into The Los Angeles Unconference”