Lpc2000

> Hi, Completely agree with you those chips' CRP are robust and
> cannot be hacked. And I never claim or seen any proven way that
> chips' CRP can be bypassed.
>  
> I'm only curious to find out if the JTAG is default as Enabled 
> for the ROM based LPC2103.  (Since bootloader is on ROM and they
> can default the JTAG to OFF).  Is that OK for you??
> Regards
>

Perhaps Section 20.8.1 of the User Manual will help.  "The Debug mode
is enabled through the use oa the DBGSEL and RTCK pins."  Actually, if
you look at the default pin connect configuration, following reset all
pins are defined as I/O.  

However, if DBGSEL is high during and after the CPU is reset, the JTAG
pins are configured for JTAG and the pin connect block settings have
no effect.

Section 20.8.2 is quite specific about how JTAG gets enabled.

So, by default JTAG is enabled if DBGSEL is high during and after the
time the CPU is reset.  Since you have no control over DBGSEL after
the device reaches a customer, you must rely on the CRP as implemented
in the bootloader.

Richard