Nowadays support for USB devices is negligible, but in the late 90s both the standard and compatibility of these devices were a real mess. Microsoft started supporting this standard in Windows 98, but it wasn’t a bed of roses.

To achieve this, Microsoft designed a terrifying test. Raymond Chen, a veteran of the company, told this in an interview on the YouTube channel of one of his former colleagues, Dave Plummer. There he told the following story:USB car of death“.

This car looked like an office stagecoach, but it was filled with USB devices that needed to work properly. He had a few mice, a keyboard, disks and a printer.

They were all chained together through various centers on three levels. At the time, the standard’s maximum limit was 127 devices, but Microsoft initially worked with 64 chained USB devicesMicrosoft decided to create a cart consisting of exactly 64 objects connected via USB, and also all these devices combine their connections into a single USB connector that can be connected to any computer.

It didn’t end there: Interestingly, to help steer and move the car, one of the connected USB devices was a video game steering wheel with a USB connection located right on the back so you could “drive” the USB car. death.

What was done next, Chen explained, was to take the car to the office of one of the developers on the team working to support the USB standard and ask him if he had a test machine. When the developer answered yes, they asked if they could plug something into it to test.

The test was precisely to use the single USB connector where the entire USB death cart ended on the test machine. What happened then? the entire USB infrastructure of the operating system was going crazy seeing 64 USB devices connected to this type of structure.

From here, the person carrying the car could test whether a connected keyboard or a mouse was working, for example. But in reality they were doing a more brutal test: wait to see how the “Plug and Play” system begins to list devices and install their drivers, and then suddenly disconnect the single connector. He then noticed that dozens of USB devices had been disconnected during installation and checked to see if the system could be recovered.

The name of the car was well deserved: the usual result when performing this test is the famous Windows blue screen of death. The code supporting the USB standard was fresh out of the oven and contained all kinds of potential conflicts that arise when faced with brutal tests like this.

What was done with this was to connect the car to the laboratory where all the testing machines were located. The car connected, waited five seconds for example, disconnected and BSOD appeared with a specific message. Then you went to another machine, but this time, after connecting and disconnecting the car, you waited seven seconds: BSOD appeared with another error.

This allowed developers debug these errors Identifying what the reason is and fixing that part of the code. This way the system won’t hang next time for that reason, but it might crash for some other reason which will then be fixed and so on until all errors are resolved.

The browser that inspires everything

Chen said the inspiration came from a disastrous event infamous in Microsoft history: the BSOD that occurred during the rollout of a preview version of the Windows 98 operating system.

On April 20, 1998, Bill Gates had to keep his cool like never before. I was at the COMDEX show promoting Windows 98 with Chris Capossela, one of the people responsible for the development of this operating system. Capossela was demonstrating how well the “Plug and Play” system worked in theory, but by connecting a browser, system down and it showed a blue screen of death (BSOD).

Caposella could only say, “Wow.” The people started laughing and applauding. Bill Gates in the suit laughed as if it wasn’t such a big deal. “That’s probably why we haven’t sold Windows 98 yet,” Bill explained. His subordinate, visibly nervous, smiled and replied, “of course.”

Now we know more about history. One of the members of this team made a revealing comment in the equally striking video we mentioned earlier from a few days ago. PatrickM, who has been working at Microsoft for 18 years and has been working on the development of USB, FireWire and Bluetooth support, explained what happened.

“The Comdex BSOD was caused by a hot dog browser that we did not test in the lab. We checked another browser on this version of the operating system, but they did not pick it up, instead went to Fry’s and bought one. The browser was “extreme” as it reported “powered by the bus” current” exception but attempted to claim more than the 500 mA a “bus-powered” device might want. The scanner went back and was mounted on an infantry helmet during World War II, which BradCarp brought to Windows WAR theaters for the remainder of the product cycle.”

This disaster helped create the “testbed” for the USB death cart, and undoubtedly helped improve support and compatibility of, yes, a standard. It continued to cause problems with the Plug and Play system for many years. (in this context, something like “Plug and Play”) which became the butt of many jokes and was renamed Plug and Pray (“Plug and Pray”).

Image | Donald Zawalczyk

in Xataka | The story of the real Windows blue screen of death and its evolution