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???
06/17/10 12:40
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 		 #176730 - Really?
Responding to: ???'s previous message
Andy Peters said:
[PER THE USB SPEC:

You CANNOT hang something on a USB port without enumerating it as a device.

Really?

I thought it was permissible to draw up to 100mA (?) without enumerating - but anything higher required enumeration?

You still have to abide by the capacitive load/maximum inrush specs.

And remeber that the spec allows that the voltage at the device end of the cable could be well under 5V...


List of 33 messages in thread
TopicAuthorDate
DC / DC Convertor            01/01/70 00:00      
   OK            01/01/70 00:00      
   that is not possible            01/01/70 00:00      
      Clarification            01/01/70 00:00      
         Select 9-12V with a capacity to supply up to 20mA            01/01/70 00:00      
            I think I see what is needed            01/01/70 00:00      
               Per forgot            01/01/70 00:00      
                  Incorrect....            01/01/70 00:00      
                     incorrect?            01/01/70 00:00      
   Getting power from the USB port            01/01/70 00:00      
      OK for Development            01/01/70 00:00      
         Required points clarified - thanks            01/01/70 00:00      
            trying again            01/01/70 00:00      
         re: OK?            01/01/70 00:00      
            The Curse Of Stuff That "Works" (sic)            01/01/70 00:00      
               USB has provisions for 1.8A from charger ports            01/01/70 00:00      
         I should know better, word of warning            01/01/70 00:00      
            Worse :(            01/01/70 00:00      
               Fuse?            01/01/70 00:00      
                  With picture            01/01/70 00:00      
                     And the external USB connectors?            01/01/70 00:00      
                     Is that really a PC motherboard?!            01/01/70 00:00      
                        Unusual USB connector.            01/01/70 00:00      
                           It all looks a bit "chunky"...            01/01/70 00:00      
                        It's a front panel board            01/01/70 00:00      
                     Both Ports??            01/01/70 00:00      
                        Yes, both ports            01/01/70 00:00      
                           Fusing S/B on main board            01/01/70 00:00      
                           Poor C6...            01/01/70 00:00      
               Bolt that stable door!            01/01/70 00:00      
      Really?            01/01/70 00:00      
         Standby?            01/01/70 00:00      
      RE: Getting power from the USB            01/01/70 00:00      

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