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???
08/16/07 14:40
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 		 #143351 - this will be a little bit too slow
Responding to: ???'s previous message
Assembling Kai's example (omitting the 'h's), then using the cycle counting feature of Jeff's disassembler (OK, a bit of self-advertisement again... :-) ):
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;
;  D52 V3.4.0 8052 Disassembly of loop.hex
;  08/16/07 16:31
;
	org	0
;
X0000:	mov	r2,#64h		     
X0002:	mov	r1,#0ffh	;  2 
X0004:	mov	r0,#0ffh	;  2 
X0006:	djnz	r0,X0006	;  4 
;
; --- Cycle count 0006-0006 = 4 * 255x = 1020
;
	djnz	r1,X0004	;  4 
;
; --- Cycle count 0004-0008 = 1026 * 255x = 261630
;
	djnz	r2,X0002	;  4 
;
; --- Cycle count 0002-000a = 261636 * 100x = 26163600
;
	cpl	p1.0		     
	sjmp	X0000		     
;
	end
;

So, even if this is a singleclocker and assuming a +-20MHz crystal, the period of blinking will be over 2 seconds. As a demonstration of functionality viable, but not nice...

JW

PS: just for the record, I called it loop.a51->loop.hex, the loop.ctl file for the disassembler contained:
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z 6*ff
z 4-8*ff
z 2-a*64

and the command line was:
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d52 loop -zds89c4x0.cyc


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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