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???
02/05/07 14:41
Modified:
  02/05/07 15:18
Read: times


 		 #132043 - wherizit?
Responding to: ???'s previous message
Tom Paden said:
And now, for the answer from NXP tech support:
-----------------------------------------------------------------
Hello Tom,
For external resets with external crystals, the reset should be long enough for the oscillator to start up (typically 10ms)
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Andy Peters said:

So why isn't that info in the data sheet!
Tom Paden said:

Ahh, it is, sort of. It's not in the "Data Sheet", but found in the User Manual, as I stated above.

I still cannot find "the reset should be long enough for the oscillator to start up" in the UM nor DS.

On the other hand, in UM I found "[when using an external oscillator >12MHz] An external circuit is required to hold the device in reset at powerup until VDD has reached its specified level.".

I still hold my opinion: this documentation is crap and the chip has a serious flaw (bad internal reset). The arrogant tone of the errata does not make this any better.

JW

{added later]PS: That webpages are also a crap. I tried to download the datasheet/user manual, what if they changed. They did not, but the web gets gradually from half-usable to completely unusable. That idiotic java-born window which follows my cursor makes me crazy. A collection of useless links (V51 migration, for example, and a bunch of ARM LPC2000 documents), the links are not properly named. I tried also standardics.nxp.com, but that's even worse: it offered me the older version of the user manual!



List of 39 messages in thread
TopicAuthorDate
min reset width?            01/01/70 00:00      
   WHY            01/01/70 00:00      
      why?            01/01/70 00:00      
      Which reset chip, and how long a pulse?            01/01/70 00:00      
      "proper supervisor"?            01/01/70 00:00      
         so why ...            01/01/70 00:00      
            Data Sheet vs User Manual            01/01/70 00:00      
               Data Sheet vs User Manual            01/01/70 00:00      
               wherizit?            01/01/70 00:00      
                  Which uP are you looking at?            01/01/70 00:00      
                     P89LPC932A1            01/01/70 00:00      
                        Hey! Where'd you get Rev 2?            01/01/70 00:00      
                           That's it: I said, it is not in the datasheet/UM!            01/01/70 00:00      
                              Webmaster? They have a webmaster?            01/01/70 00:00      
         Only at 5V...            01/01/70 00:00      
         words, words            01/01/70 00:00      
   Does it not have an internal Reset circuit?            01/01/70 00:00      
      now THIS is a BAD documentation            01/01/70 00:00      
         Does it imply            01/01/70 00:00      
            infernal reset (not a typo!)            01/01/70 00:00      
               So, what's the "right" way?            01/01/70 00:00      
                  don't use it as a port pin            01/01/70 00:00      
                     It's not a pitty but a shame!            01/01/70 00:00      
                        it's "creeping feature"-ism            01/01/70 00:00      
                           not a waste            01/01/70 00:00      
         Yes, I remember those many complaints!!            01/01/70 00:00      
         And what about...            01/01/70 00:00      
            internally timed            01/01/70 00:00      
               I LOVE it            01/01/70 00:00      
                  OK so let's vote            01/01/70 00:00      
                     no voting, please            01/01/70 00:00      
                        this is not taste, but facts            01/01/70 00:00      
   So, how's one supposed to reset this thing?            01/01/70 00:00      
   lets see...            01/01/70 00:00      
      Yes, but what's REQUIRED?            01/01/70 00:00      
   Some results            01/01/70 00:00      
      with or without the reset chip?            01/01/70 00:00      
         now with the reset chips            01/01/70 00:00      
            and the troubles were BEFORE or AFTER?            01/01/70 00:00      

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