Re:Tell HN: Alexa mute button is not hardwired
by beatgammit on Sunday January 06, 2019 @03:30AM
(#18837289)
The Librem 5 claims to have hardware switches for the radios, and it's not even out yet.
Yes, most modern devices don't have these switches, and yes it's more expensive to put them in, but hopefully it's not completely going away. I like knowing that something is off (software can fail, whether intentionally or unintentionally), and I'm willing to pay a little extra for that.
I hope we haven't completely ignored lessons from Spectre/Meltdown. Trusting the CPU isn't acceptable, so certain things should have a hardware shut-off to ensure malware can't break through (e.g. Purism's laptops have hardware switches for the camera and other components, which is awesome given the Snowdon leaks).
It leads to a smaller simpler design to simply hook all switches and lights into a CPU and have software control everything. It lets the UX be decided later in the design process, it allows the design to be modified to other usecases more easily, and it simplifies the testing required for each device produced.
Having 'hardware' switches also tends to be significantly harder to design. For example, a hardware mic switch might bounce when switched, and cause voltage transients which damage the ADC. Such things are very hard to predict before the design is produced, and might only affect a small percentage of produced devices meaning it gets missed in testing.