Lpc2000

After Much hair pulling, I discovered you are partially correct. The
IO pins must be set as "Input". port 0.27 - 0.31 all must be set as
inputs, after this the device will come up under the secondary JTAG
control.

HOWEVER - the connection can only be made marginally, sometimes it
will, sometimes it wont. Reason unknown. After finally succesfully
connecting using the Secondary JTAG, I tried to reprogram, and the
program cycle failed (Right after it managed to erase the part), DOPE,
now it's back to square 1.

My suggestion for would be users of this feature would be: Make sure
you make your board such that no modification is required to switch
between Primary, and Secondary JTAG. Use the Primary to program, and
secondary to debug.

QUESTION: why does the pinsel block not actually disconnect the IO
from the Direction register?

--- In lpc2100@yahoogroups.com, Robert Adsett <subscriptions@a...> wrote:
> Check through the notes on Philips microcontroller discussion list.
 I seem 
> to remember a mention that the pin directions had to be set to match
what 
> the JTAG required.
> 
> Robert
> 
> At 09:53 PM 1/20/04 +0000, you wrote:
> >----------------------- assumption: ------------
> >
> >I have made the assumption that since the code 0x554000 has bee placed
> >into the pinsel1 register, the port direction register has no effect
> >on the pins any longer.
> 
> " '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