See story about taser malfunction [via TNT] that caused a taser to emit an uncontrolled 20 second duration shock.
The gist of the story is that the taser in question was reportedly rebooting and "therefore" the taser continued to emit the shock while it was going through the lengthy boot-up sequence.
If you're unfamiliar with the intimate details of how embedded processors function, then this explanation might appear to be reasonable. But that's not a correct conclusion.
In fact, this explanation reveals that the systems designers and the management of Taser International are flaming idiots (as if we didn't already know). Stupid and obviously ill-informed of normal best practices for embedded design.
To be clear - It is absolutely trivial to choose a circuit architecture and default hardware logic polarities such that uncontrolled shocks would be inherently eliminated. For example, when making a choice between active-high versus active-low logic for a given internal control signal, you simply stop and think which choice is safer. It adds 5 seconds to the design process. But you have to have to concept of "safe" somewhere in the corporate thought process.
Given this hardware design mistake, then the obvious workaround is to update the software so that 'hardware state cleanup' is done as the FIRST order of business at boot-up. You change the code so that it makes sure that (for example) the shock is OFF as the first thing on boot-up. This fix would at least reduce the duration of the uncontrolled shock to a small fraction of a second. This sort of work-around is a poor second choice compared to designing the hardware properly in the first place.
Plaintiff lawyers could use this as yet another example that clearly highlights the incompetence of the designers and management of Taser International.
Assumning the reported facts are correct, my follow-on conclusions (above) are beyond dispute.
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