Longtime hardware/sw geek, for fun&profit; nowadays Embedded Systems and RE. Doing this for a living is like getting paid to eat cake. linkedin: richaplin

San Francisco, CA
Joined October 2008
Enjoying seeing "Trump makes speech" as a minor news story, and scrolling right on by, because no fucks given.
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DrTune retweeted
Having a very smart person take you through a series of counterintuitive ideas is exciting in the same way that watching a great athlete is, plus afterward you get to keep the ideas.
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I vividly remember my one mains-voltage electric shock; 240v up the arm, was 11years old; my own fault, a VERY salutory lesson. Never since. ...Did you ever get a good zap?
20% 110v
51% 240v
16% >240v (!)
14% Not yet! ..touch wood ;-)
429 votes • Final results
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Followup; Do you have a Ground Fault Circuit Interrupter on the power in your lab/work-space, and have you tested it?
25% Unsure / Definitely not
4% Err..maybe? Not my job
23% I have fuse/breaker; ok?*
48% Yes, and I tested it
56 votes • Final results
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(* just having a fused outlet or a (non-GFCI) circuit breaker is definitely not ok at all and you are crazy risking your life for lack of something that costs peanuts)
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I worked on an EV charger, and I implemented the ground-fault detect hardware on it (which passed UL certification), and it was not at all trivial. GFCI's are wonderful inventions.
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PSA; fuses / breakers / surge-protectors are to stop your house burning down. They will NOT stop you getting electrocuted. A GFCI will, very effectively. A GFCI has a test button on it (which literally shorts the live rail to ground). Easy option: tinyurl.com/x8znumu9
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GFCI's clever; measure current flowing out of live and back through neutral wires and requires them to match almost exactly; any imbalance means some is escaping to ground - maybe through a person! Cuts power within milliseconds of detecting just a few milliamps. Saved many lives
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note you can still get electrocuted if you touch both live and neutral at the same time - nothing is going to save you from that, frankly - but it's much more common for a hot wire to flow through you (or e.g. a grounded metal case) to ground; tripping the GFCI (a.k.a RCD)
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My main point is you can just buy a GFCI / RCD socket splitter or extension cable (make sure it actually has GFCI) and plug it inline with all the crap on your bench and just forget about it - it literally might stop you getting killed by some cheap thing you bought online.
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DrTune retweeted
Running code on Raspberry Pi 3A VPU🥳. The VPU is a managment core on the Raspberry GPU, trough the mailbox interface its possible to execute code on it. Here I toggle GPIO2 directly from the VPU, the CPU just idles in Linux that moment :) Free realtime core yay !
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I don't know why this is so funny but..
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Tidied up! - this is "pristine" by local standards. So satisfying I've scheduled a repeat session for 2031. ;-) Also; those "70w" (~30w) 12v white COB plates ($14) have very thin profile, great on manfrotto/gooseneck/coathanger as floating work light, doesn't block monitors
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if you run them at a sensible (and still bright) 50% power they don't need heatsink, total about 2.5mm thick. This is my normal line of sight - the led plate fits between the bezels of the adjacent monitors
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Oldskool!
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I remember seeing an interview with @bunniestudios when he mentioned the Chumby tchotchkes and what a time-sink they were; looking at them now I wonder "what were they _thinking_?" (retro shout to @xobs who worked on the firmware) ..Last thing in my house that runs Flash!
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DrTune retweeted
universal parallel bus
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