RE: PCI 2.2 question

[Neal Palmer <neal@dinigroup.com>]

That bug is "seen" in NT when the processor is idle.  NT will generate
special cycles on PCI in motherboards that support the generation of
special cycles when all of the processes running are IDLE.  
  You can mostly get around that problem by running a process that
basically does:

while (1) {
	sleep(0);
}

Then the processor will never be idle, and won't send out the special
cycles on PCI.  Most people tend to not like this solution because the
load on the machine will stay at 100%.

-- neal

On Tue, 11 Apr 2000, Reasoner, George E wrote:

> I was also having problems using a PCI board with the AMCC S5933QE in a
> newer computer when using bus master transfers. It turns out that there is a
> "bug" in the S5933QE that is activated by Special Cycles on the PCI Bus
> where the IDSEL signal is active during the Special Cycle. This is
> documented in http://www.amcc.com/pdfs/SumQE4.pdf. Apparently the chipsets
> in the newer computers are aggravating this bug. AMCC has a new part, the
> S5935QF that is a drop-in replacement for most applications. It took care of
> the problem for us.
> 
> Regards,
> George Reasoner
> Unisys Corporation
> 
> -----Original Message-----
> From: Allen, Douglas [mailto:Douglas_Allen@perkinelmer.com]
> Sent: Tuesday, April 11, 2000 2:23 PM
> To: ''
> Subject: PCI 2.2 question
> 
> 
> A couple of years ago, I designed a PCI board using the AMCC 5933QE chip.
> Recently, I found that
> I was receiving data errors when running the board on some newer computers.
> So far, the only common
> thread I see is that all of the computers on which it fails are specified as
> PCI V2.2. Are there known
> issues when using a PCI 2.1 board in a PCI 2.2 bus? Since I have not been
> designing PCI cards of late, 
> I was wondering if there was something I did not take into account with the
> new spec.
> 
> Any help would be greatly appreciated.
> 
> Thanks.
> 
> Mark Allen
> Douglas_Allen@perkinelmer.com
> 

-- Neal Palmer

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