Lpc2000

It boots fine from flash at power on, so the checksum etc. is OK.  
And when it hangs after a watchdog "reset", pulling RESET# low can 
also reboot it correctly.
So has anybody actually seen the watchdog reset work?

Karl Olsen


--- In lpc2000@yahoogroups.com, "Kerem Or" <k.or@s...> wrote:
> 
> according to user manual:
> 
> if P0.14 is high while RESET#=0 then LPC attempts to execute user 
> code (if a valid csum found at addr 0x14). It does not enter ISP 
> mode. I suppose this is your case as described below
> 
> If P0.14 is low while RESET#=0 but also the watchdog overflow flag 
> is set, then LPC ignores the state of P0.14 and attempts to start 
> user code.
> 
> In both cases a valid checksum is required at location 0x14 for LPC 
> to execute user code
> 
> more details in the manual (p217)
> 
> Kerem
> 
> 
> --- In lpc2000@yahoogroups.com, "Karl Olsen" <kro@p...> wrote:
> > 
> > --- In lpc2000@yahoogroups.com, "Kerem Or" <k.or@s...> wrote:
> > > Then let the watchdog expire. It will reset the chip but will 
> not 
> > change the 
> > > state of the reset pin. That means your external hardware (if 
> you 
> > have any) 
> > > connected to the LPC reset pin will not get reset.
> > 
> > Has anybody done this successfully?
> > 
> > On my LPC2114, I have tried doing a CPU reset by starting the 
> > watchdog and letting it expire.  But when it expires, the CPU 
just 
> > hangs, without restarting.  P0.14 isn't low, and it hasn't 
entered 
> > ISP mode.  I'm doing like this:
> > 
> > WDT->WDTC = PCLK_HZ/4; /* Timeout = 1 second */
> > WDT->WDMOD = 0x03;
> > WDT->WDFEED = 0xAA;
> > WDT->WDFEED = 0x55;
> > 
> > At this time I can see WDTV decrementing, and when it reaches 
> zero, 
> > the system just hangs, and interrupt activity stops.
> > 
> > Karl Olsen