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Re: Hardware Watchdog


Christoph Csebits <christoph.csebits@frequentis.com> writes:

> On Fri, Jul 27, 2001 at 08:48:14AM +0200, Robin Farine wrote:
> > Ok, have you already tried to configure the GPIO pin as *input*? This would
> > set the line in high-impedance mode and the MAX should disable its watchdog
> > function. Check your ROM startup code for access to the GPDR (IO direction
> > register). Then, in the application, reconfigure this bit as output to use the
> > watchdog.
> 
> basically its right, but the hardware designers
> made a good job of it, and there is a pull down
> resistor preventing the watchdog input from floating.
> (which would disable the watchdog timer)

That's exactly what I suspected :-(

> 
> i dont think the soldering iron is an acceptable solution. :-)
> 

Why not? I would call this a design flaw and report it to the manufacturer. The
fact that a place for a pull down resistor exists is a good thing (we have seen
some chips with specified internal pull down/up resistors but in the reality,
those pins were floating so we now always put some pads just in case), but in
this case the resistor should not be fitted.

Robin


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