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???
02/14/10 01:12
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#173145 - tied EA high still no luck
Responding to: ???'s previous message
I also changed the code to simple , just set and clear port p2.7 every 2 secs , but something is not working.


$MOD51
;
; The processor clock speed is 11.059MHz
; Cycle time is 1.1ms

	input_port  equ p2.0
	output_port equ p2.7

	org	00
	ljmp	main

	org 100h
main:


loop:	setb	output_port		;port 2.7 should blink
	lcall   wait_2s
        clr	output_port	
 	sjmp 	loop




;---------------------- delay routines    ----------------------------------

wait_2s:
	mov	r5,#20
b1:	lcall	wait_135ms
	djnz	r5,b1
	ret

wait_135ms:
	mov	r2,#255		;1x1.04us
	mov	r3,#255		;1x1.04us
loop1:	djnz	r3,loop1	;250X10x2.07us
	mov	r3,#255		;10x1.04us
	djnz	r2,loop1	;10x2.07us
	ret			;
;------------------------- end delay -----------------------------------


 	end 

 



List of 5 messages in thread
TopicAuthorDate
problems programming the P89V51            01/01/70 00:00      
   here is the schematic I am following            01/01/70 00:00      
      EA            01/01/70 00:00      
         tied EA high still no luck            01/01/70 00:00      
   PROBLEM FIXED - Working now            01/01/70 00:00      

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