Fixing The Fix For A 3dfx Voodoo Card’s Overly Bright Picture

After previously fixing an overly bright picture from a Voodoo graphics card with a simple resistor on one of the RAMDAC’s pins to correct its faulty internal Vref, [Bits und Bolts] got called out for not taking component drift into account. Thus in an update video he shows how instead to use an adjustable AMS1117 voltage regulator to hopefully prevent either the original issue or something new and exciting from cropping up later.

The basic idea here is to use the external voltage reference (Vref) pin for this ICS5342 RAMDAC and supply it with a constant 1.235V. If unused – as on this Orchid-branded Voodoo card – it is connected via an 0.1 microFarad capacitor to ground. This fortunately means that the pin is routed to easily accessible pads that make this modification relatively straightforward.

Basically this is where the AMS1117-ADJ chip comes into the picture, as a widely available adjustable LDO option, even if the 0.8A current rating is very much overkill for this application. With the supplied voltage the lowest voltage this LDO can output is around 1.25V, which is within the 1.10 – 1.35 V range of the datasheet.

Of course, with the PCB never having had a provision for this part, much of the rest of the video is about planning out where to place and route the components. After that tedious work and testing that nothing explodes, the new voltage is used for the RAMDAC’s Vref pin, fixing the brightness issue.

While one could argue that this RAMDAC is likely simply defective and already beginning to break down inside, this should at least give it a bit longer on what seems to be a little used card anyway.

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Documenting The IR Protocol Of The PumpSaver Plus Device

Having a pump in a remote location where you aren’t constantly monitoring it is a common scenario, which can be unfortunate when said pump runs into problems like a dry well, jammed impeller or power issues. This is where pump monitors like the older SymCom (now Littelfuse) PumpSaver Plus 233P will protect the pump if such conditions are detected. Of course, the infrared communication port on it uses an undocumented protocol that was meant to be used with a long-since discontinued handheld device. Ergo [Elizabeth Camporeale] saw fit to reverse-engineer this protocol.

In the installation manual for this device this Informer unit is briefly mentioned along with the information it will display on its screen, making it clear that it’s quite literally just there to act as a display for the information that’s constantly generated on this interface. Naturally, this is incredibly useful if you wish to tie the system into a wider monitoring and automation system.

Somewhat unusual, this IR interface on the used 233P-1.5 unit turned out to be use a 5,000 baud NRZ, MSB-first protocol, with the juicy details fully documented and a Python-based decoder implementation provided.

Naturally [Elizabeth] didn’t just reverse-engineer this for the fun of it, but also for ESPHome integration. This uses a setup as can be seen in the top image, with an ESP32-C6 module providing the processing power and Wi-Fi, with a standard phototransistor recording the data pumped out by the pump monitor.

Mechanosynthesis Of Atomic Carbon Structures Using Inverted-Mode STM

Generally chemical synthesis involves putting a variety of compounds together in an environment where they will react and self-assemble into the desired product. You could also imagine simply putting the atoms in the right place: direct mechanical manipulation. This mechanosynthesis is however not that simple, despite the deceptive appearance of those ball-and-stick representations in high school chemistry class.

This is demonstrated in a recent (pre-publication) study by [Megan Cowie] et al. using inverted-mode STM. Using a scanning tunneling microscope (STM) you can measure a surface on a nanoscale, with the inversed principle used in inverted-mode STM (IM-STM) to physically move individual molecules. In the paper the construction of carbon-based 3D structures using IM-STM is demonstrated.

In the paper it is demonstrated how C2 units can be moved using the tip of an IM-STM setup for subsequent polyyne structure construction through C-C bond formation at the target site. Although it’s not quite yet the leap into Neal Stephenson’s The Diamond Age with its science-based matter compilers – i.e. molecular assemblers – it’s definitely another step closer to making advanced feats of nanotechnology a part of every day life.

Reviving Mystery Nintendo 64 Game Cartridge Found In The Woods

As far as things go that you are likely to find during a relaxing walk in the forest, Nintendo 64 game cartridges probably do not rank high on that list. Yet this is what happened to a friend of [BlueBox Tinkers] a few years back, leaving him dying to see whether the cartridge would still work, as well as what game it is since its labels got obliterated courtesy of its time spent enjoying the outdoors. Fortunately he recently got a chance to see whether he could revive this cartridge.

The insides look pretty much like what you’d expect after presumably months or years of exposure, with the metal shield severely corroded. The PCB does however look pretty decent still, with obvious signs of corrosion on the front-side vias, and a pretty gross-looking back side.

Unfortunately it wasn’t confirmed whether this friend tried to stick this old cartridge into an N64 console, but [BlueBox Tinkers] wasn’t going to take any such chances. First up was an inspection and deep cleaning of the PCB, showing that it had escaped real damage, with the shield having taken the brunt of the corrosion. Cleaning up the shield and the insides of the plastic shell is by far the hardest part, with the pitted metal and rust stuck on the plastic. For a full restoration you’d probably want to for a reproduction shell and shield here.

Ultimately the game turned out to still work, with the mystery game sadly fairly predictable, but with someone’s old save files still intact. Somehow it seems that what Nintendo did to make N64 cartridges dust- and child-resistant also makes it survive in the woods, so if you find one during a forest walk, it’s totally worth it to adopt it and take it home.

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IBM Home Director: Home Automation In 1996

Back in the 1990s IBM had a pretty sizeable presence in the PC market, including its rather spiffy Aptiva series of PCs. Naturally their PCs had to feature heavily in another consumer-related thing that was popular in the 1990s, being smart home automation in the form of IBM Home Director. Recently [Ionic1k] took a look at this blast from the past, starting with one of the original IBM commercials.

At its core it used the same X10 protocol that similar solutions from RadioShack and others used, with many modules and packages you could get to use with it. You could also get a more bespoke installation performed at your home to move beyond mere X10, which some people are still finding when they’re buying a house.

Since this uses powerline communication, it required no wires to be run, just the requisite modules to be plugged into a power outlet, with the video demonstrating the basic setup and installation. The PC itself is plugged into the control module via the serial port, from which the Home Director control software can be used to create a configuration and control the state of connected modules.

Although X10 has the same issues as any kind of powerline communication, overall it seems like a very nice system, with a wide range of modules and absolutely easy to set up even for a casual Windows user.

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Hacking Amazon Echo Show 8 3rd Gen Via UART And EMMC

Even with Amazon’s Echo Show devices running Linux in the form of the Android-derived FireOS, using them for non-Amazon approved purposes can be a chore at best. In the case of the Echo Show 8 even simple workarounds using ADB and the bootloader have been locked-down, requiring more drastic measures. Here [Vowed] over at the XDA forums shows off one such hack, involving directly tapping into the device’s eMMC.

Suffice it to say that this is not a hack for the faint of heart, with even the iFixit teardown guide for this device being rather daunting. Even after you get access to the mainboard, you still have to remove or cut open the metal can that covers the eMMC, so that you can unleash an eMMC programmer on it. It’s best to make sure to make a backup image of the original contents too, just in case you have to restore things.

With the shield out of the way you can solder fine wires to pads that connect to the eMMC to program it. You also have to solder wires to pads for the UART, though if you’re fancy you can also create a custom pogo pin adapter. With a serial connection established to the original firmware you can then enable features like ADB, and courtesy of the connected eMMC adapter it’s possible to directly alter system files to make rooting as easy as possible.

In addition to rooting the system you can also do a straight replacement of the eMMC contents, such as the demonstrated Debian installation. Even if not the most easy of mods, it’s good to see that it’s possible to repurpose these devices.

(Top image: Amazon Echo Show 8 3rd generation mainboard. Credit: iFixit, CC BY-NC-SA 3.0.)

Reverse Engineering And Self-Hosting The OBI Smart Energy Tracker

Sold by German DIY store OBI, the OBI Energy Tracker is a €15 set of two devices, one of which you essentially stick on top of your existing electricity meter. This then allows for electricity usage to be measured and tracked, with the data sent to the second, gateway device. This latter cloud-bound device is linked to an OBI account via the heyOBI app. This correspondingly called for the gateway device to be reverse-engineered and freed from its cloud-based shackles, a task that [Aaron Christophel] happily took upon himself.

The whole process is also covered in two videos, with the first providing all the essentials on reprovisioning the original firmware for a local MQTT server in English, while the second, German-language video focuses on custom firmware for the ESP32-C3 inside of the gateway device.

Inside the reader device is a Cortex-M0+-based BAT32G135 MCU that communicates with the meter via its IR protocol. This is then communicated via 868 MHz LoRa to the gateway device that will be placed somewhere within Wi-Fi reach by the user. Inside this latter device is as mentioned the ESP32-C3, which by default runs firmware that communicates via secure MQTT with an AWS cloud instance for the typical cloud-based shenanigans.

The aforementioned reprovisioning option doesn’t require firmware flashing, just a handful of steps to follow. This involves fetching the 32-bit TEA key, generating your own PKI, running your own MQTTS-capable broker and having the provided Python script handle the rest from there.

Flashing custom firmware is the other option, with straightforward UART/JTAG reflashing sadly disabled by the manufacturer. With the effort required here you could perhaps argue that simply connecting the reader device to a custom gateway device might be a lot easier, especially if you already have a LoRa transceiver and associated hardware.

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