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???
01/12/07 22:53
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 		 #130754 - why not ?
Responding to: ???'s previous message
It is however not advised to play with LEDs and ports.
Why not?
I use low current LEDs with series resistors driven by port pins all the time for status indication on the board.

However, the first part of your statement is right "It is however not advised to play with", "playing with", to me, means doing something without proper calculations based on datasheets before designing and that is definitely "not advised".

For instance the first LEDs on this page http://dkc3.digikey.com/PDF/T071/2100.pdf are clearly visisble at 2-5 mA.

Of course, if the ports sink capability is less than the LED current you try to get, then "It is disatrous to play with LEDs and ports".

If anyone is stupid enough to believe your posts about "current limiting port pins", then, of course, "It is however not advised to play with LEDs and ports", however two wrongs do not make a right

Erik

List of 62 messages in thread
TopicAuthorDate
how can i use port 0 as output            01/01/70 00:00      
   read            01/01/70 00:00      
      not quite understand            01/01/70 00:00      
         READ            01/01/70 00:00      
            i'm blur            01/01/70 00:00      
               it is a \'1\', but not a \'high\'            01/01/70 00:00      
         Port 0 is open drain            01/01/70 00:00      
            connection between u-c with pull up?            01/01/70 00:00      
               Basics            01/01/70 00:00      
                  typo            01/01/70 00:00      
                     Doh!            01/01/70 00:00      
               The answer is...            01/01/70 00:00      
                  Sinking and Sourcing            01/01/70 00:00      
                     Correct!            01/01/70 00:00      
                  sending data using port 0?            01/01/70 00:00      
                     Yes            01/01/70 00:00      
                        LED display driver            01/01/70 00:00      
                           Port1 is better than port0 for this            01/01/70 00:00      
                              is it right like this?            01/01/70 00:00      
                                 NO            01/01/70 00:00      
                                 Where is the TB62726 in your circuit??            01/01/70 00:00      
                                    stiil stuck with port0            01/01/70 00:00      
                                       help me plz            01/01/70 00:00      
                                          drop the cute stuff            01/01/70 00:00      
                                    connections right or not?            01/01/70 00:00      
                                       Hallelujah!!            01/01/70 00:00      
                                          I already did            01/01/70 00:00      
                                          sorry            01/01/70 00:00      
                                       No            01/01/70 00:00      
                                 Looks like a point of confusion            01/01/70 00:00      
                                    It is not Right            01/01/70 00:00      
                                    Looks like total confusion!            01/01/70 00:00      
                                       looks like?            01/01/70 00:00      
                                    confused..            01/01/70 00:00      
                                       That is Right            01/01/70 00:00      
                                       the schematic is fine, BUT            01/01/70 00:00      
                                       You have damaged the micro!!            01/01/70 00:00      
                                    my assumption right now            01/01/70 00:00      
                                       basics            01/01/70 00:00      
                                          Deja Vu            01/01/70 00:00      
                                          Wyh not?            01/01/70 00:00      
                                             the difference is            01/01/70 00:00      
                                       See my recent post.            01/01/70 00:00      
                                          why not ?            01/01/70 00:00      
                                          No, you're wrong ...            01/01/70 00:00      
   Don't remove your earlier schematics!!            01/01/70 00:00      
      RightO            01/01/70 00:00      
         a good way to burn the port pin (and the LED)            01/01/70 00:00      
            Sorry Datasheet is different for what I am saying            01/01/70 00:00      
               NO, nada, niente, never, nie, non,, aldrig            01/01/70 00:00      
               Hair-raising...            01/01/70 00:00      
               Completely Incorrect!            01/01/70 00:00      
                  In practice..            01/01/70 00:00      
                     Please read specs properly            01/01/70 00:00      
                        What has survived your "tests" must be correct?            01/01/70 00:00      
      diagram attached            01/01/70 00:00      
         Connections are not correct!            01/01/70 00:00      
   Modifications            01/01/70 00:00      
      PWM without using 8051-Timer            01/01/70 00:00      
         New Topic; New Thread            01/01/70 00:00      
         Yes, but...            01/01/70 00:00      
         the usual question            01/01/70 00:00      

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