[Search for users] [Overall Top Noters] [List of all Conferences] [Download this site]

Conference 7.286::fddi

Title:FDDI - The Next Generation
Moderator:NETCAD::STEFANI
Created:Thu Apr 27 1989
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:2259
Total number of notes:8590

2003.0. "bus mastering on our EISA FDDI ?" by BIGUN::wills.cao.dec.com::PINKERTON (Coo-ee Digger Wombat Mate) Tue Apr 02 1996 03:55

I am getting some FUD from a customer regarding our FDDI EISA card.  
I need some anti-FUD please.

The customer is hearing from Cisco that our DEFEA (FDDI EISA card) uses IRQs
rather than bus mastering and therefore is "old technology".  I do not know
much about this stuff, and therefore need some information to get back at this
mis-information.  In ten sentences or less what is the pros and cons of our
EISA FDDI card with regard to bus mastering / IRQ.  This information hinges
us winning the NIC business.  Any information would be useful.  The cards are going 
in Compaq servers, and so far are the only cards that are passing the 
customers tests.  Cisco are already in the account.  

I am sorry that I do 
not know much more, as I am getting this information from someone else also.

TIA

Neil
T.RTitleUserPersonal
Name		DateLines
2003.1FDDIcontroller/EISA *is* a Bus Master DMA DeviceNETCAD::PAQUETTETue Apr 02 1996 08:3826
Cisco is slinging the FUD.

FDDIcontroller/EISA (DEFEA) is certainly a DMA Bus Master Device.  This
adapter uses the same Digital-Designed DMA Bus Master architecture as some
of our other FDDIcontrollers like DEFPA, DEFTA, DEFQA, DEFAA.  It is based
on Digital's PDQ Bus Master DMA chip.

The use of IRQ's is not mutually exclusive with DMA Bus Mastering.  Yes, the
DEFEA needs to be assigned an IRQ in the system, just like any other 
Bus Master DMA device.  DEFEA supports IRQs 9,10,11,15.

Perhaps what is causing the confusion is that the DEFEA requires no system
DMA channels.  System DMA channels are for devices that use a slave-mode
DMA, and require the on-board system DMA controller to move data to/from the
adapter.   In an old DEFEA SPD, it lists the DMA Channel Selections Supported
as NONE, with the note that the FDDIcontroller/EISA is a DMA Bus Master and
does not use a system DMA channel.

If you are looking for some "ammo" to use with DEFEA (and if you can read
French!), you should know that the DEFEA was just rated the #1 FDDI/EISA
card in a comparison done in the April 1, 1996 issue of Dicision Micro
magazine in France.  The competition included: Madge, IBM, Syskonnect, 3Com,
and D-Link.

Regards,
Mike P.
2003.2STRWRS::KOCH_PIt never hurts to ask...Tue Apr 02 1996 08:556
    Well, that interesting since I just got an advertisement in the mail
    from Network Peripherals Inc which says was running the Novell 3
    Perform Benchmark our EISA controllers were the *worst* performers of
    NPI, SysKonnect & 3COM.
2003.3Perform3 Results may varyNETCAD::PAQUETTETue Apr 02 1996 13:4910
You can change a lot of parameters when running Perform3 that will affect the
results of a test.  Traditionally, with DEFEA, we do better with larger
numbers of clients in the Perform3 tests.  How many clients were used in the
test that NPI shows?  Also, packet size affects the results. DEFEA did best
with 4K packet sizes...

Could I get a copy of the advertisement that you reference?

	Thanks,
	Mike P.
2003.4NETCAD::STEFANITue Apr 02 1996 13:5326
    >>Well, that interesting since I just got an advertisement in the mail
    >>from Network Peripherals Inc which says was running the Novell 3
    >>Perform Benchmark our EISA controllers were the *worst* performers of
    >>NPI, SysKonnect & 3COM.
    
    That can't be correct, since NPI (like 3Com) has used LANQuest which is
    an independent testing lab in California.  In LANQuest reports I've
    read on FDDI EISA cards, the DEFEA is always mysteriously absent. 
    Probably because they wouldn't see the desired results.  If the NPI
    advertisement includes performance data, please FAX it to me at DTN:
    226-6311.
    
    The DEFEA has always been favorably priced and a top performer. 
    The reason it may not sell as well as other NICs is because Digital
    chooses to not advertise the NICs as much as other companies.
    
    With regards to Cisco, they are more or less out of the NIC business. 
    Ask them when they're coming out with an FDDI PCI adapter.  Look at the
    dates on their SW kits and see how well they keep their FDDI EISA
    drivers up to date.  The results will probably surprise you.
    
    Since buying Crescendo, Cisco has been more interested in keeping their
    hub, switch, and router line alive than their FDDI NIC business.
    
    - Larry