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???
02/19/07 23:35
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 		 #133271 - Question on "No-Touch" and watchdog
I have a question concerning the use of the No-Touch code in an application.

The No-Touch code terminates in an infinite loop, waiting for the watchdog timer to reset the part.

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     mov  r1,#6h       ;program status byte (No Watchdog!)
     mov  dptr,#0      ;specify status byte
     mov  a,#0ffh      ;nonzero required
     call 0fff0h       ; IAP Call to set status byte
     jmp  $            ;wait for watchdog to reset

This implies that the watchdog is active. However, the IAP call is made assuming the watchdog is off (r1 = 06h instead of r1 = 86h). So what keeps the watchdog from triggering in the middle of the IAP call, and causing all sorts of terrible things to happen?

Or am I just missing something obvious here? I am definitely a noob on IAP / ISP.


List of 27 messages in thread
TopicAuthorDate
Question on "No-Touch" and watchdog            01/01/70 00:00      
   I maybe missing something too            01/01/70 00:00      
   byte programming time            01/01/70 00:00      
      the reason is            01/01/70 00:00      
         the point is somewhere else...            01/01/70 00:00      
         The reason I asked is...            01/01/70 00:00      
            Noob???            01/01/70 00:00      
               Yes, Noob            01/01/70 00:00      
                  re phil ARGH NXP IAP            01/01/70 00:00      
                     Flash Magic            01/01/70 00:00      
                        NoTouch LPC900            01/01/70 00:00      
                           correct            01/01/70 00:00      
            He can't possibly give a _solution_....            01/01/70 00:00      
               no touch for 936            01/01/70 00:00      
                  a word from the author            01/01/70 00:00      
                     ok but            01/01/70 00:00      
                        Joes 935 works, what is the question?            01/01/70 00:00      
                           backdoor & no touch            01/01/70 00:00      
                              the difference            01/01/70 00:00      
                                 It is ok            01/01/70 00:00      
   idea            01/01/70 00:00      
      you would not know about ISP, would you            01/01/70 00:00      
   if it is the 'H' chips (Rx2H and C66x) , then            01/01/70 00:00      
      Setting the Watchdog            01/01/70 00:00      
         i referred to NOT setting the watchdog during ISP            01/01/70 00:00      
         Lynn - What is your original requirement?            01/01/70 00:00      
            Original Requirement            01/01/70 00:00      

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