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   REPLYADDR JL@gct.com   
   REPLYTO 3:770/3.0 UUCP   
   MSGID:  eb8962ef   
   PID: SoupGate-Win32 v1.05   
   XPost: sci.electronics.design   
      
   The RP2040 has a cool mode where it can be made to boot up with the   
   USB port looking like a memory stick. That's great for software   
   installs or upgrades. The Pico board has a BOOT button on the board;   
   if the pico is powered up with the button pushed, it goes into that   
   boot mode.   
      
   But if I have a product (actually a family of products) in a nice   
   aluminum box, a user would have to remove the top cover, remove all   
   power sources (there can be three), and hold the button down while   
   reconnecting power.   
      
   Some of my customers also want to lock a box such that it's impossible   
   to write to any nonvolatile memory while it's in a secure area.   
      
   So here's an idea: a small hole in the box allows a toothpick or a   
   paper clip to push a button. A short push is a regular reset. A long   
   push is a memory-stick mode boot. We can have a rotary switch LOCK   
   hole too.   
      
   https://www.dropbox.com/scl/fi/bbhdy053xsdzv77g0brc5/B-box_Reset   
   Button_3.jpg?rlkey=40ozzdvczf4z8625u8i081a9b&raw=1   
      
   Does that look like it will work? The paranoid customer can pave over   
   the two holes, and even the end-plate screws, with an official-looking   
   sticker.   
      
   Schmitt trigger U3 is unfortunate and likely unnecessary, but it   
   insures against a low-probability hazard.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: Agency HUB, Dunedin - New Zealand | Fido<>Usenet Gateway (3:770/3)   
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