Back in the golden age of modems and phone lines, bulletin board systems, or BBSes, were a great way to find new software from the comfort of your own home. Most have shut down over the past few decades, as the Internet took over as a more flexible method of cat picture software distribution. [equant] was a fan of browsing for warez through a text interface however, so recreated the experience in a way that’s useful today. The result is RetroBridgeBBS.
The software runs on a modern PC, ideally a Linux one that runs Python 3 and has a serial port. Then, you can hook up your old retro computers via serial using a null modem cable. Fire up appropriate terminal software on the retro computer and you’re rewarded with a BBS-like interface. From here, you can search selected online repositories for software, and download what you like. The host PC parses requests from the retro PC over the serial link, and shuffles back the requested files downloaded from the Internet. Currently it’s set up primarily for Macintosh users, with some useful features to avoid downloading StuffIt archives of the wrong version – a perennial frustration in the 90s. Future plans involve expanding the system to suit more platforms.
The original Xbox was well-known for being based on basic PC hardware, and among developers, well known for having just 64 megabytes of RAM which even at the time wasn’t a lot to be working with. In a recent podcast, [Todd Howard] of Bethesda related an anecdote from the era, claiming that Morrowind occasionally invisibly rebooted the Xbox without user’s knowledge in order to free up RAM. [Modern Vintage Gamer] wanted to determine if this was true or not, and began an investigation.
The investigation begins with the aid of an Xbox Development Kit. Noting that the original anecdote mentioned the reboots occurring during the loading process, the devkit Xbox was soft rebooted after executing a load. Rather than going back to the title screen of the game, it kicked straight back into the loading screen and brought up the last save game instead. This suggested that the game was indeed capable of rebooting in the midst of the loading routine.
[Modern Vintage Gamer] had a hunch that this was being achieved with the use of a routine called XLaunchNew Image, a piece of the Xbox API that could be used to soft-reboot the console and start an executable. Upon decompiling Morrowind, a call was found that fit the bill. Further analysis showed that the game was indeed calling XLaunchNewImage upon loading and launching a new game, and was confirmed by finding an *.ini file that contained flags to enable this behaviour.
Presumably, the reason for this behaviour was that it was simpler to boot the game fresh when loading a save, rather than trying to unload all the game assets in memory from the current game. It’s a neat trick that likely made the development team’s lives much easier once they implemented it.
Active suspensions are almost a holy grail for cars, adding so much performance gain that certain types have even been banned from Formula 1 racing. That doesn’t stop them from being used on a wide variety of luxury and performance cars, though, as they can easily be tuned on the fly for comfort or improved handling. They also can be fitted to remote controlled cars as [Indeterminate Design] shows with this electronic servo-operated active suspension system for his RC truck.
Each of the four servos used in this build is linked to the mounting point of the existing coilover suspension on the truck. This allows the servo to change the angle that the suspension is positioned while the truck is moving. As a result, the truck has a dramatic performance enhancement including a tighter turning radius, more stability, and the capability of doing donuts. The control system runs on an Arduino with an ESP32 to enable live streaming of data, and also includes an MPU6050 to monitor the position of the truck’s frame while it is in motion.
There’s a lot going on in this build especially with regard to the control system that handles all of the servos. Right now it’s only programmed to try to keep the truck’s body relatively level, but [Indeterminate Design] plans to program several additional control modes in the future. There’s a lot of considerations to make with a system like this, and even more if you want to accommodate for Rocket League-like jumps. Continue reading “Remote Controlled Car Gets Active Suspension”→
The 1980s and early 1990s were a bit of an odd time for semiconductor technology, with the various transistor technologies that had been used over the decades slowly making way for CMOS technology. The 1991-vintage IBM ES/9000 mainframe was one of the last systems to be built around bipolar transistor technology, with [Ken Shirriff] tearing into one of the processor modules (TCM) that made up one of these mainframes.
Five of these Thermal Conduction Modules (127.5 mm a side) made up the processor in these old mainframes. Most of note are the use of the aforementioned bipolar transistors and the use of DCS-based (differential current switch) logic. With the already power-hungry bipolar transistors driven to their limit in the ES/9000, and the use of rather massive DCS gates, each TCM was not only fed many amperes of electricity, but also capable of dissipating up to 600 Watts of power.
Each TCM didn’t contain a single large die of bipolar transistors either, but instead many smaller dies were bonded on a specially prepared ceramic layer in which the wiring was added through a very precise process. While an absolute marvel of engineering, the ES/9000 was essentially a flop, and by 1997 IBM too would move fully to CMOS transistor technology.
SV Seeker is a home-made boat currently being built by [Doug Jackson] just north of Tulsa, Oklahoma. It’s a bit different than what you might imagine as a typical DIY boat, though. You see, Seeker is a 75 ft steel boat, intended to work as a research vessel. Doug and his crew proudly refer to Seeker as “The boat the internet built”, and he’s our kind of people. We’ve covered them before, the first time way back in 2013. Doug’s Youtube channel does double duty, both teaching the rest of us all the skills he’s learned while building, and also serving as the eventual user and repair manual for the boat. Continue reading “SV Seeker Is Recycling Batteries”→
Closed captioning on television and subtitles on DVD, Blu-ray, and streaming media are taken for granted today. But it wasn’t always so. In fact, it was quite a struggle for captioning to become commonplace. Back in the early 2000s, I unexpectedly found myself involved in a variety of closed captioning projects, both designing hardware and consulting with engineering teams at various consumer electronics manufacturers. I may have been the last engineer working with analog captioning as everyone else moved on to digital.
But before digging in, there is a lot of confusing and imprecise language floating around on this topic. Let’s establish some definitions. I often use the word captioning which encompasses both closed captions and subtitles:
Closed Captions: Transmitted in a non-visible manner as textual data. Usually they can be enabled or disabled by the user. In the NTSC system, it’s often referred to as Line 21, since it was transmitted on video line number 21 in the Vertical Blanking Interval (VBI).
Subtitles: Rendered in a graphical format and overlaid onto the video / film. Usually they cannot be turned off. Also called open or hard captions.
The text contained in captions generally falls into one of three categories. Pure dialogue (nothing more) is often the style of captioning you see in subtitles on a DVD or Blu-ray. Ordinary captioning includes the dialogue, but with the addition of occasional cues for music or a non-visible event (a doorbell ringing, for example). Finally, “Subtitles for the Deaf or Hard-of-hearing” (SDH) is a more verbose style that adds even more descriptive information about the program, including the speaker’s name, off-camera events, etc.
Roughly speaking, closed captions are targeting the deaf and hard of hearing audience. Subtitles are targeting an audience who can hear the program but want to view the dialogue for some reason, like understanding a foreign movie or learning a new language.
It’s 2021. Everyone and their mother is filming themselves doing stuff, and a lot of it is super cool content. But since most of us have to also work the video capture devices ourselves, it can be difficult to make compelling footage with a single, stationary overhead view, especially when there are a lot of steps involved. A slider rig is a good start, but the ability to move the camera in three dimensions programmatically is really where it’s at.
[KronBjorn]’s excellent automated overhead camera assistant runs on an Arduino Mega and is operated by typing commands in the serial monitor. It can pan ±20° from straight down and moves in three axes on NEMA-17 stepper motors. It moves really smoothly, which you can see in the videos after the break. The plastic-minimal design is interesting and reminds us a bit of an ophthalmoscopephoropter — that’s that main rig at the eye doctor. There’s only one thing that would make this better, and that’s a dedicated macro pad.
If you want to build your own, you’re in luck — there’s quite a lot of detail to this project, including a complete BOM, all the STLs, code, and even assembly videos of the 3D-printed parts and the electronics. Slide past the break to check out a couple of brief demo videos.