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???
02/01/06 14:38
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 		 #108891 - The confusion arises...
Responding to: ???'s previous message
If every port pin on every processor in the world had the same quasi-bidirectional structure, there'd be no confusion.

Trouble is, some processors do have specific "Port Direction" registers that are totally separate from the Ports' "Data" register - and you do have to specifically configure pins to be "Inputs" or "Outputs".
The AVR is an example.
(I think that old crock the 8255 is similar?)

Thus, if someone comes from another processor and is used to having to deal with a "Port Direction" (or "Data Direction") register - and they hear people talking about "configuring" 8051 pins "as inputs" or "as outputs" - they could waste ages trying to find the 8051's "Port Direction" (or "Data Direction") registers!!

Worse yet, some modern 8051 derivatives do have pins that do specifically require that you write something to a real "Port Configuration" SFR...!!

Confusion abounds!!

List of 51 messages in thread
TopicAuthorDate
initializing a port as output            01/01/70 00:00      
   STOP THE BABBLE            01/01/70 00:00      
      Keil says....            01/01/70 00:00      
         Keil is wrong!            01/01/70 00:00      
            what about the bible itself            01/01/70 00:00      
               the issue is not if someone can find ref            01/01/70 00:00      
                  Dont see any confusion            01/01/70 00:00      
                     what works            01/01/70 00:00      
                     The confusion arises...            01/01/70 00:00      
                        yes that may be the thing            01/01/70 00:00      
                  We talk about the "Bible"!            01/01/70 00:00      
                     it really is a wired or configuration            01/01/70 00:00      
                        No disagree            01/01/70 00:00      
                        I agree, but all are not equal            01/01/70 00:00      
         Confguring......            01/01/70 00:00      
   Quasi bidirectional            01/01/70 00:00      
      NO, NO, NO STOP THE BABBLE            01/01/70 00:00      
         there is only output mode            01/01/70 00:00      
            no, there is NO mode!!!!!!!!!!!!!            01/01/70 00:00      
         Who is babbling?            01/01/70 00:00      
            Maybe Rude but right            01/01/70 00:00      
               Mode clarified            01/01/70 00:00      
                  No, that's wrong            01/01/70 00:00      
                     i see            01/01/70 00:00      
                     Why is this wrong??            01/01/70 00:00      
                        playing with words            01/01/70 00:00      
                           Yes            01/01/70 00:00      
                           "Mode" is the word            01/01/70 00:00      
                              what i meant            01/01/70 00:00      
                  No            01/01/70 00:00      
                     which mode            01/01/70 00:00      
                     lets play with words            01/01/70 00:00      
                  Exception            01/01/70 00:00      
                     see this            01/01/70 00:00      
                     a valid, sometimes overlooked point            01/01/70 00:00      
                        Indeed            01/01/70 00:00      
               Yes, but weak or strong            01/01/70 00:00      
            yes and no            01/01/70 00:00      
               Yes, that's it!            01/01/70 00:00      
                  one more word            01/01/70 00:00      
         What a Rudeness            01/01/70 00:00      
   No input output            01/01/70 00:00      
      Just read the port!!!!!!!!!!!!!!!1            01/01/70 00:00      
         yes            01/01/70 00:00      
            not offending            01/01/70 00:00      
               not really            01/01/70 00:00      
                  see what keil says            01/01/70 00:00      
                     about "rudeness"            01/01/70 00:00      
                        No excuse            01/01/70 00:00      
                           what agression, what rudeness            01/01/70 00:00      
                              Haha!            01/01/70 00:00      

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