ARM LP2200 + Wiggler JTAG ?

1/ JTAG - RTCK ? It is the Return Clock. It is used for deglitching the 
return signal.
Ideally, the chip under test would have zero delay getting the clock on
board. But it does have some delay. The RTCK is the image to of the
JTAG clock being used by the chip. For very fast clocking, this allows
the debugger to sync up with the chip under test.
http://www.embeddedrelated.com/groups/lpc2000/show/12619.php

2/ In any case, the Wiggler clock is probably much too slow for RTCK to 
be very useful unless the target ARM is being clocked at a much slower 
than normal speed. RTCK has been VERY useful for very high speed JTAG 
debuggers like TRACE32.
http://www.embeddedrelated.com/groups/lpc2000/show/12640.php

3/ [LPC2000 Datasheet]
Note: LOW on RTCK while RESET is LOW enables pins P1.31:26 [= JTAG-Port] 
to operate as Debug port after reset.
http://www.embeddedrelated.com/groups/lpc2000/show/9177.php

Ich würde das LPC2200 Datasheet dazu durchlesen und dann wahrscheinlich 
wie in 3/ RTCK über 10K Widerstand zu GND verbinden, um den JTAG-Port 
einzuschalten.

http://olimex.com/dev/images/arm-jtag-layout.gif ist die Pinbelegung des 
20poligen JTAG-Standard-Steckers.