Lpc2000

David Hawkins wrote:

>  > > An idea:
>  > >
>  > > When debugging with JTAG, often the program runs out of SRAM.
>  > > Unless the loader explicitly clears RAM (eg. the .bss area),
>  > > then there is a chance that you will see differences between
>  > > a cold start (pulling the plug) versus a warm start (any form
>  > > of reset).
>  > >
>  > > So, if you code looks at some variable that you assume to be
>  > > zero - change it to explicitly set that variable to zero
>  > > (making it part of the data section).
>  > >
>  >
>  > The startup code from Rowley clears ram first I think, and all my
>  > variables are initialized at powerup anyway. It seems to be related to
>  > the hardware registers, maybe the VIC setup, that are causing problems.
>  >
> 
> The data sheet usually specifies a 'reset value' for registers,
> so normally those registers will be cleared.
> 
> Try a flash RAM version of the program. Hit reset with that
> loaded. At least that will convince you that the problem is RAM
> program related. Since in that case the VIC will be reset the same
> as in the RAM test case.
> 

Actually it is running from flash. It looks like it gets reflashed each 
time it reloads. I'm wondering if there is a difference between a soft 
reset and a powerup reset? Time to dig through the PDF's again (this is 
on a LPC2138).

Thanks,

Brian

-- 
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Brian C. Lane (W7BCL)                      Programmer
www.shinemicro.com   RF, DSP & Microcontroller Design