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???
08/16/07 14:09
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 		 #143348 - Sink instead of source
Responding to: ???'s previous message
Your micro cannot source enough current to drive the LED, but only sink. So, connect one end of your resistor to Vcc (instead to ground), connect the other end of this resistor to anode of LED and connect the cathode of LED to P1.0.

Also, your code is unsuited, because it makes the LED blink too fast! So fast, that you cannot see the blinking with your eyes. I would recommend to use an internal timer, or at least an enhanced waiting loop. For instance, the loop code snippet could look like that:



Save This Code
           led1 equ p1.0 

loop:      mov r2, #100h 
loop2:     mov r1, #255h
loop1:     mov r0, #255h
loop0:     djnz r0, loop0
           djnz r1, loop1
           djnz r2, loop2 
        
           cpl led1 
        
           sjmp loop


Kai


List of 33 messages in thread
TopicAuthorDate
blinking LED won't blink            01/01/70 00:00      
   Describe The Connection            01/01/70 00:00      
      show your schematic            01/01/70 00:00      
         how true            01/01/70 00:00      
   it IS blinking, but you don\'t see it it\'s too fast            01/01/70 00:00      
      You're right, Jan! It is a 16,384 MHz one-clocker            01/01/70 00:00      
   before Andy or Erik runs on you...            01/01/70 00:00      
      40pin PDIP, he mentioned the eval board...            01/01/70 00:00      
         and what?            01/01/70 00:00      
            Very suspicious            01/01/70 00:00      
               Ignore him            01/01/70 00:00      
                  But then he learns nothing            01/01/70 00:00      
                     Valid point! It's about documentation!            01/01/70 00:00      
                  .. or ask for additional info...            01/01/70 00:00      
               Does anybody see a "proper" reset?            01/01/70 00:00      
         and so what?            01/01/70 00:00      
            He\'s being optimistic            01/01/70 00:00      
               18 messages so far.            01/01/70 00:00      
   Are you using the on-board LED\'s?            01/01/70 00:00      
      How many people do we need            01/01/70 00:00      
         just two:            01/01/70 00:00      
            zero            01/01/70 00:00      
         You forgot YOUR contribution to the list...            01/01/70 00:00      
   blinking LED wont blionk with schematics            01/01/70 00:00      
      Sink instead of source            01/01/70 00:00      
         mov r1,#255h?            01/01/70 00:00      
            OP used "#255h". Knows the hell...            01/01/70 00:00      
         this will be a little bit too slow            01/01/70 00:00      
            What would be a nice blinking period??            01/01/70 00:00      
               OK, OK....            01/01/70 00:00      
                  I also had a long day...            01/01/70 00:00      
    Reply:blinking LED won't blink            01/01/70 00:00      
      No need            01/01/70 00:00      

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