p> Date: Wed, 28 Jan 2004 17:31:54 +0000 p> From: "Miha Dolenc" mihad@flextronics.si> p> Subject: Re: [pci] PCI transfer rate p> p> Maximum theoretical bandwidth of PCI bus at 32 bit, 33 MHz is arround p> 130MBps, so I doubt that you can find any device supporting that kind of p> throughput. I don't know anything about this core but I have been achieving speeds in excess of 100 MB/s with commercial 32/33 bridges such as V360EPC and PCI9054. /Mikhail

One of my boards (with an Altera PCI core) does not limit the transfer speed at all when mounted in a 'normal' PC. The bandwidth only depends on the speed of motherboard, CPU, RAM and/or chipset. I have measured between 50MB/s and 90MB/s at different motherboards. I only write to the board. Conclusion: Your limitations are most likely not in the Opencore PCI. If you are running another platform then Intel-based PC you will get other results. Have Fun STB -----Ursprungligt meddelande----- Från: pci-bounces@opencores.org [mailto:pci-bounces@opencores.org] För Mikhail Matusov Skickat: den 29 januari 2004 21:43 Till: pci@opencores.org Ämne: [pci] Re: Re: PCI transfer rate (Miha Dolenc) p> Date: Wed, 28 Jan 2004 17:31:54 +0000 p> From: "Miha Dolenc" mihad@flextronics.si> p> Subject: Re: [pci] PCI transfer rate p> p> Maximum theoretical bandwidth of PCI bus at 32 bit, 33 MHz is arround p> 130MBps, so I doubt that you can find any device supporting that kind of p> throughput. I don't know anything about this core but I have been achieving speeds in excess of 100 MB/s with commercial 32/33 bridges such as V360EPC and PCI9054. /Mikhail _______________________________________________ http://www.opencores.org/mailman/listinfo/pci

Hi,

The latency timer that is determined by the BIOS software makes a tremendous
difference.
On some motherboards I saw, PCI bandwidth was limited to 10 (!!!!) MB/sec
just because the latency timer was programmed to some stupid small value.

The BIOS usually tries to honour latency requests by all cards at once, so
if you have the misfortune of sharing the system with a card that wants
instantaneous bus access whenever it likes, and the BIOS grants this, you
end up with small bus slots and performance goes down the drain.

Kind regards,
-----Original Message----- From: Stefan Bergström [mailto:stb@viking2001.se] Sent: vrijdag 30 januari 2004 9:14 To: 'Discussion list about free, open source PCI IP core' Subject: Re: [pci] Re: Re: PCI transfer rate (Miha Dolenc) One of my boards (with an Altera PCI core) does not limit the transfer speed at all when mounted in a 'normal' PC. The bandwidth only depends on the speed of motherboard, CPU, RAM and/or chipset. I have measured between 50MB/s and 90MB/s at different motherboards. I only write to the board. Conclusion: Your limitations are most likely not in the Opencore PCI. If you are running another platform then Intel-based PC you will get other results. Have Fun STB -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.opencores.org/forums/pci/attachments/20040130/45c9c8b3/attachment.htm