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by buildbot 1893 days ago
I've recently started working with firewire, and man what an interesting bus. You've got isochronous and asynchronous support simultaneously, awesome! But then you get this: "Voltage is specified as unregulated and should nominally be about 25 volts (range 24 to 30)" Looking at the nearest firewire device on my table, it will certainly blow up if I get near it with 25 volts. It's like USB-C without any negotiation!
1 comments

I worked on the FireWire driver stack for OS X... and we encountered many incidents of managing to plug in the 6-pin connector upside down. Devices will actually catch fire. (FireWire carries up to 45W (!) at 30v)

Also, isochronous mode is great in theory, but in practice, at least in a desktop computer, the rest of the machine internals are not isochronous so you can still run into real-time delivery failures.

> Devices will actually catch fire.

A rare case of successful naming, then.

I know I shouldn't be surprised, but how can that keyed connector get forced in backwards? That is mind-boggling.
The metal shell of the 6-pin socket has a seam where it's closed, and that can open or loosen with use. That makes it easy (enough) to plug in a connector the wrong way.

Trivia: Pretty sure the 6-pin FireWire connector was inspired by the GameBoy link cable connector. https://en.wikipedia.org/wiki/Game_Link_Cable