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???
12/26/07 20:16
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 		 #148738 - the reason for circular buffers
Responding to: ???'s previous message
The ADC holds the result in the ADC SFRs until it finishes next conversion. Also, the UART holds the received byte on SBUF until the end of next byte reception.
Then, is there any difference from direct polling of the ADC flag or RI in the main loop?

discussing the UART only, same applies to all other

The reason for circular buffers is that, when using interrupts (i.e. not foolishly suffering from interruptifobia) and circular buffers the average main loop time must be less than the average character separation time. When using polling the maximum main loop time must be less than the minumum character separation time.
Thus, if e.g. the main loop occasionally does a time consuming process polling will fall apart, but circular buffered interrupts will not.

Erik

List of 34 messages in thread
TopicAuthorDate
Having problem on using interrupt            01/01/70 00:00      
   Answers            01/01/70 00:00      
      not so fast, Cristoph and to Ragu            01/01/70 00:00      
         Serial comm is slow.            01/01/70 00:00      
            if you read the OP            01/01/70 00:00      
               good interupts            01/01/70 00:00      
                  AAAAAARGH            01/01/70 00:00      
                     not AAAAAAAARGH            01/01/70 00:00      
                        OH YES            01/01/70 00:00      
                           do You ever avoid "non-debuggable"?            01/01/70 00:00      
                              always            01/01/70 00:00      
                                 nice            01/01/70 00:00      
                                    a trick for "long ISRs" better than a RTOS            01/01/70 00:00      
         Buffered RX            01/01/70 00:00      
            not much difference            01/01/70 00:00      
               You are right            01/01/70 00:00      
   Sucess with interrupts            01/01/70 00:00      
      Isn't it too short?            01/01/70 00:00      
         the reason for circular buffers            01/01/70 00:00      
            Worst case, instead of average            01/01/70 00:00      
               absolutely, just worst case is not as bad            01/01/70 00:00      
                  single, double and ring buffer            01/01/70 00:00      
                     single, double and ring buffer app dependent            01/01/70 00:00      
         and some more reasons to use (circular) buffers            01/01/70 00:00      
            buffer overflow error            01/01/70 00:00      
               Buffer overflow handling            01/01/70 00:00      
                  Buffering options            01/01/70 00:00      
                     Beauty contest !            01/01/70 00:00      
                        flexible is the best?            01/01/70 00:00      
                        Simplicity is always better            01/01/70 00:00      
                           simple is another word for            01/01/70 00:00      
                              Where is the borderline to stumble on            01/01/70 00:00      
                                 Copper Oxide            01/01/70 00:00      
               please exclude me from the 'we'            01/01/70 00:00      

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