Lpc2000

Thanks for your help.  The contents at 0x00000000 were different 
because it was in Bootloader mode instead of Flash mode.  This is 
because I left P0.14 open and its unintionally entering ISP mode on 
reset.  Should be an easy fix with a pullup, we'll see!

-- Kathy



--- In lpc2000@...m, Tom Walsh <tom@...> wrote:
>
> kathy_wright_ca wrote:
> 
> >I've been developing code for several months on the Keil 2130 
board 
> >with a 2138 - no problems I haven't been able to figure out so 
far. 
> >
> >  
> >
> Your best bet is to get some type of JTAG running so that you can 
debug 
> the code.  Depending on your JTAG, you may need to place a loop at 
the 
> startup entry label to give the processor some delay so the JTAG 
can 
> reset the board and catch the processor before it starts to excute 
any 
> code beyond the delay loop.  This is what I use on the LPC2106 to 
allow 
> an Abatron BDI2000 to "catch" the processor:
> 
> ============ begin crt0.S ================
> _start:
> start:
> ;
>       ldr   r0, JTAG2
>       ldr   r1, PINSELREG
>       str   r0, [r1]       // activate secondary JTAG port.
> ;
>       mov   r3, #0x10000
> startdelay:
>       subs  r3, r3, #1
>       bne   startdelay     // give debugger time to catch us.
> ;
> 
> ============== snip ===================
> 
> The above delay is needed on the LPC2106 as I am switching to the 
> secondary JTAG and the BDI2000 has no control until that code 
executes.  
> On the LPC2138, no loop is needed as it catches the processor 
nicely at 
> the first opcode.  With a wiggler (lower speed JTAG device), you 
may 
> still need a slight delay loop to catch the processor before it 
slams 
> into whatever bad code you have.
> 
> 
> Regards,
> 
> TomW
> 
> 
> -- 
> Tom Walsh - WN3L - Embedded Systems Consultant
> http://openhardware.net, http://cyberiansoftware.com
> "Windows? No thanks, I have work to do..."
> ----------------------------------------------------
>