re: PCI PM polarity of PMCSR bit

[Brian Belmont <a0192894@decmail.itg.ti.com>]

>  From: pontius@west.smc.com (Mark Pontius x4805), on 3/10/97 2:46 PM:
>  Brian,
>  
>  Did you just make a mistake again?  Your last sentance says that writing a 0
>  to this bit will clear it.  That is how it is in 0.99a, not 0.90.
>  
>  --Mark
>  
>
>  > 
>  > 
>  > >  From: pontius@west.smc.com (Mark Pontius x4805), on 3/10/97 11:43 AM:
>  > >  The value written to the PMCSR register required to clear the 
>  PME_Status has
>  > >  inverted between the 0.90 and 0.99a releases of the PCI Power 
>  Management 
>  > >  Spec.
>  > >  
>  > >  The PMCSR register, bit 15, PME_Status:
>  > >          v0.90: Writing a 1 to this bit will clear it
>  > >          v0.99a: Writing a 0 to this bit will clear it
>  > >  
>  > >  Why was this changed?  Was it a typo?
>  > >  I believe the 0.90 method is more logical, since PCI already uses the
>  > >  mechanism of writing a 1 to clear status in the interrupt register: 
>  config
>  > >  space, address 4 (text on bottom of pg 191 in the PCI rev 2.1 spec).
>  > >  
>  > >  --Mark Pontius
>  > >    SMC
>  > 
>  > The PME_Status bit was erroneously inverted in the 0.99a version of the 
>  PCI
>  > Power Management spec.  The bit has been changed back to it's original 
>  polarity
>  > (as documented in v0.90) and this change will be reflected in the next 
>  posting
>  > of the specification which should be the official version submitted for 
>  the SIG
>  > 30-day review.  
>  > 
>  > The Power Managment Working group apologizes for any confusion generated 
>  by
>  > this oversite.  Again, the correct version will follow the PCI precedent 
>  and
>  > writing a 0 to this bit will clear it (Bit 15 of PMCSR).
>  >   

Arrgh! Apologies, once again!  You are correct, Mark.  The last sentence SHOULD
say:

the correct version will follow the PCI precedent and writing a 1 to this bit
will clear it (Bit 15 of PMCSR).

Terribly Sorry,
Brian Belmont		Voice: 	972.997.6021
Texas Instruments	Fax:	972.997.6301
PC Systems Lab		MsgID:	BVB1
					Internet: bbelmont@ti.com
Ö,