Lpc2000

Ok, there is a software solution... ;-)

   Sten

--- In lpc2000@yahoogroups.com, "Bill Knight" <BillK@t...> wrote:
>
> IIRC some external watchdog timer chips force a reset on timeout only
> if their input pin is held high or low for too long a period.  If the
> pin is left floating, the watchdog function is disabled.  See the TI
> TPS382x family info (SLVA039 section 10).  The boot loader most likely
> leaves unused GPIO pins unconfigured so they should be in their
> default mode as inputs.  If that case the floating connection to the
> watchdog chip should disable the timed reset function.
> 
> Good luck
> -Bill Knight
> R O SoftWare &
> http://www.theARMPatch.com
> 
> 
> On Mon, 17 Oct 2005 12:17:58 -0000, bdmlpc wrote:
> 
> >Hello,
> 
> >bad foul!!! I think there is no software solution (except hacking the
> >philips bootloader). You could insert a single gate (NAND) into the
> >/reset signal that disables /reset (=1) while P0.14 (for entering
> >bootloader programming mode) is low during programming. 
> 
> >  Sten
> 
> >--- In lpc2000@yahoogroups.com, "lhaddix" <lhaddix@i...> wrote:
> >>
> >> Hi,
> >> I'm working on an LPC2138 design and just moved
> >> into ESD testing. After some ESD hits there was
> >> no damage, but the processor would be left not 
> >> running.
> >> 
> >> Implementing the internal watchdog didn't fix this.
> >> 
> >> Apparently there are ways to nail a 2138 with ESD
> >> that must stop the processor clock and thus also
> >> prevent the internal watchdog from working.
> >> 
> >> My solution is an external supervisor chip with a
> >> watchdog function that I would keep strobed with
> >> some line from the micro.
> >> 
> >> I know this will work because when an ESD hit 'stuns'
> >> the LPC2138 I can restart it by toggling reset.
> >> 
> >> The problem is I want to use the internal flash loader
> >> to do the factory program load for my board.
> >> 
> >> The flash loader will not keep my external watchdog strobed
> >> and will not be able to avoid a reset as a result. So the
> >> external watchdog will keep it from working.
> >> 
> >> Question: Does the phillips flash loader toggle and pin
> >> regularly that I could use for this strobe?
> >> 
> >> Can I hook it somehow to make it pet the dog?
> >> 
> >> Any ideas?
> >> 
> >> Landrum
> >>
> 
> 
> 
> 
> 
> 
> 
> > 
> >Yahoo! Groups Links
> 
> 
> 
> >
>