Re: Any way to force a 64-bit transaction

[Neal Palmer <neal@dinigroup.com>]

Michael,

We have had the same problem (same motherboard).  We can't get it to
assert Req64.  One solution is to use an Intel/DEC P2P 64-bit bridge.  It
will convert the 32-bit burst write into a 64-bit burst write (under
certain conditions).

Also, on this first set of 64/66 PCI chipsets, you are far better off if
you can manage to initiate DMA operations instead of using the CPU to push
data.  The next generation of chipsets might not have this "limitation".

-- Neal

On Fri, 28 Apr 2000, Michael Richardson wrote:

> 
>   We have a 64/66 card.
>   We are testing it against a Micron Samurai chipset motherboard with
> an Intel processor.
> 
>   We are looking for a way to *force* a 64-bit write from our (PIII) CPU to
> our device so that we can test our handling of 64-bit operations. So far
> we have been unable to find a way to do this.
> 
>   Does anyone have any suggestions? Does it matter how we map the device?
> (Cacheable vs non-cachable) Are there any extra instructions on PIII that 
> might help us? Since it is really a 32-bit CPU with a 64-bit external bus,
> there is not (to my knowledge) a 64-bit write.
> 
>    :!mcr!:            |  Solidum Systems Corporation, http://www.solidum.com
>    Michael Richardson |For a better connected world,where data flows faster<tm>
>  Personal: http://www.sandelman.ottawa.on.ca/People/Michael_Richardson/Bio.html
> 	mailto:mcr@sandelman.ottawa.on.ca	mailto:mcr@solidum.com
> 
> 
> 

-- Neal Palmer

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