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???
10/06/06 12:14
Modified:
  10/06/06 13:09
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 		 #125900 - good material????
Responding to: ???'s previous message
using HC chips and resistors, instead of dedicated LED driver chip such as the ST2221A and C (50ma constant current drive) or similar offerings from Allego, Rohm and others. Is that "good advice".

In addition it is multiplexed which will make a Moving message display a pain in the you know what.

A multiplexed "Moving message display" must synchronize multiplexing, PWM intensity and scroll which put severe demand on the processor. OK, if you have a display of, say, 8*24, sure, but how much text can you show on that?

Erik

Charles, this is not towards you personally, it is towards all those so called designs that hardly give the LEDs enough power to be seen at midnight drived form the alarm clock display, where intensity is hardly an issue. I have heard the reply "use high efficiency LEDs" which is pure unfiltered male cow manure, since the added cost of using high efficieny LEDs will be far more than what you save by multiplexing.

List of 34 messages in thread
TopicAuthorDate
LED Moving Message Display Code            01/01/70 00:00      
   vague question            01/01/70 00:00      
      If he knew that, he wouldn't be asking            01/01/70 00:00      
   link            01/01/70 00:00      
   details required            01/01/70 00:00      
      How to post schematics, etc            01/01/70 00:00      
         is that true?            01/01/70 00:00      
            Unfortunately so            01/01/70 00:00      
            Just take a look!            01/01/70 00:00      
   this is homework            01/01/70 00:00      
      OR            01/01/70 00:00      
   Good material can be found here            01/01/70 00:00      
      These things are so ubiqitious            01/01/70 00:00      
         An ideal homework project, then!            01/01/70 00:00      
      AT90S2313            01/01/70 00:00      
         Schematic shows AT90S2313 but 80C51...            01/01/70 00:00      
            Only pulling your leg, Charles!            01/01/70 00:00      
      Chips            01/01/70 00:00      
      good material????            01/01/70 00:00      
         schematics required            01/01/70 00:00      
   however...            01/01/70 00:00      
      In my travels I see these signs everywhere            01/01/70 00:00      
         not, fi built by the "good design"            01/01/70 00:00      
            TWICE YOU HAVE INSULTED ME. APOLOGIZE!            01/01/70 00:00      
               No way Charles Grow up            01/01/70 00:00      
               how can that be            01/01/70 00:00      
               Idiot            01/01/70 00:00      
               not new            01/01/70 00:00      
                  Please Stop Discussion on This Thread            01/01/70 00:00      
                     ... next time ...            01/01/70 00:00      
                  what insults?            01/01/70 00:00      
         Sun light blinding            01/01/70 00:00      
   In today's comic...            01/01/70 00:00      
      I know of apps for these, but hardly "on-topic"            01/01/70 00:00      

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