Lpc2000

Robert, 

Thanks. The thing is that I built this board myself so I'm guessing that it
is due to my negligence of some kind and not the chip's fault. I tested the
Sec. JTAG prior to this implementation and it seemed to work just fine on
the Ashling LPC dev board. I wasn't gonna clone that board, so I obviously
don't have the same power section. 

How could one explain the fact that shorting 3.3V supply will somehow
kickstart it?.. beats me. I tried all kinds of tricks.. holding the reset,
shorting individual JTAG pins. 

I'll keep poking it in during some off hours :-) 

Cheers,

m.

  

 

  _____  

From: Robert Adsett [mailto:subscriptions@...] 
Sent: Tuesday, February 01, 2005 11:34 PM
To: lpc2000@yahoogroups.com
Subject: Re: [lpc2000] Question: Secondary JTAG internals

 

At 09:16 PM 2/1/05 -0500, Milos Prokic wrote:
>I was wondering if anyone has any information regarding the secondary JTAG
-
>internal structure. I'm battling a problem that I can only connect to JTAG
>after I've SHORTed the 3.3 V line. My powerup sequence is - first core
>(1.8v) and then IOs (3.3v) (btw there is nothing in the datasheet that
>mentions the sequence, so I presumed it wouldn't matter). Without shorting
>the tool will refuse to connect, but once shorted - works like a charm.


Philips has stated, and my experience has been, that there is not a 
sequencing issue on power up.  I suspect you've got something else going 
on.   I've not used the secondary JTAG myself, but it does appear to cause 
people no end of troubles.

Robert

" 'Freedom' has no meaning of itself.  There are always restrictions,
be they legal, genetic, or physical.  If you don't believe me, try to
chew a radio signal. "

                         Kelvin Throop, III




  _____  

Yahoo! Groups Links

*	To visit your group on the web, go to:
http://groups.yahoo.com/group/lpc2000/
  
*	To unsubscribe from this group, send an email to:
lpc2000-unsubscribe@yahoogroups.com
<mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe> 
  
*	Your use of Yahoo! Groups is subject to the Yahoo!
<http://docs.yahoo.com/info/terms/>  Terms of Service. 



[Non-text portions of this message have been removed]