Messages in this thread | | | Date | Wed, 5 Aug 2009 12:31:27 +0200 | From | Wim Van Sebroeck <> | Subject | Re: [PATCH] Add watchdog driver for w90p910 |
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Hi Wan,
> > I have an additional question: which timeout values can you set? is it 0, 1, 2 and 3 seconds? > > The 0, 1, 2 and 3 is not seconds, rather than 'level' , it means my > watchdog controller can only set four grades, > When WTIS bit of REG_WTCR was set one value of the 0, 1, 2 and 3, the > real time interval can be calculated via following formula . > > WTIS real time interval (formula) > 0x00 ((2^ 14 ) * ((external crystal freq) / 256))seconds > 0x01 ((2^ 16 ) * ((external crystal freq) / 256))seconds > 0x02 ((2^ 18 ) * ((external crystal freq) / 256))seconds > 0x03 ((2^ 20 ) * ((external crystal freq) / 256))seconds > > The external crystal freq is 15Mhz in w90p910 evaluation board. so I > set the '0x00' as a default value, it means the real time interval is > 0.28 second approximately.
Hmm, the watchdog API works in seconds. A timer will need to be used like in similar watchdog drivers (like at91sam9_wdt.c, pcwd.c).
Kind regards, Wim.
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