I'm looking at my 16C5X book (cause I'm too lazy to find the 73 book) but i
think this is the same. look at the /PD flag during power on reset it is set
to '1' and after a watchdog reset it is set to '0'. look for a table called
'Reset conditions for special registers'

michael

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-----Original Message-----
From: Eric Earnst <earnst@SPRINTMAIL.COM>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Wednesday, October 28, 1998 12:35 AM
Subject: WDT vs. MCLR resets


>Hi all,
>>From looking at the datasheet for a 16C73A it looks like there is no
>reliable way to tell if a reset occurred from a WDT reset or a MCLR
>reset.  It appears that NOT_TO = 0 is intended to indicate that a WDT
>reset occurred, however since NOT_TO is undefined after a MCLR "Reset
>during normal operation" a test of NOT_TO is not a reliable way to
>differentiate between a WDT reset and, in my case, a reset switch reset.
>
>I'd like to set up the box I am building so that if a WDT reset occurs I
>can blink an LED with a pattern indicating where the code was before the
>reset.  The user would then hit a reset switch attached to MCLR to
>restart the code.  I was also going to use the reset as a general
>purpose abort that would clean up the outputs and halt the code.  So I
>guess I have two problems, I can't tell for sure if the reset occurred
>from the WDT or from a user hitting the reset switch (MCLR).
>
>Any ideas beyond not using MCLR to reset and instead just putting it on
>a port that I poll (or PORTB interrupt)?
>
>Thanks,
>Eric
>