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Conference turris::digital_unix

Title:	DIGITAL UNIX(FORMERLY KNOWN AS DEC OSF/1)
Notice:	Welcome to the Digital UNIX Conference
Moderator:	SMURF::DENHAM

Created:	Thu Mar 16 1995
Last Modified:	Fri Jun 06 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	10068
Total number of notes:	35879

9553.0. "Can DE500 auto-sense or auto-detect speed on dunix" by CSC32::A_LICAUSE () Fri Apr 18 1997 11:17

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    All references to the DE500 indicate that the device must be told at
    the console or using ifconfig on a dunix system, at what speed it will
    run.
    
    Is this true or is the interface capable of auto-sensing the speed
    based on the hub or remote device it is talking to?
    
    If it can autosense, what are the correct settings to allow it to do
    this?
    
    If not, can someone give a brief explaination as to why auto sensing
    does not or cannot work?
    
    This note is cross posted in the ETHERWORKS conference as well.  
        
    Thanks,
    Al

T.R	Title	User	Personal Name	Date	Lines
9553.1		alphy.lkg.dec.com::thomas	The Code Warrior	`Fri Apr 18 1997 13:36`	14
	The answer depends on which DE500 variant you talking about. The DE500-XA can sense 10 or 100 Mb/s but not duplex. The DE500-AA and DE500-BA can sense 10 or 100 Mb but can also participate in 802.3u autonegotiation (NWAY support). This allows the card to negotiate which of the modes it should operate in. Much of this autosensing support is done by the driver with a bit of hardware assist. Note that the tu driver will autosense media if there is no mode set at the console level. More recent consoles also have an autoneg mode for the DE500-AA. I don't know if the consoles support the DE500-BA yet.
9553.2	More info	SMURF::GILLUM	Kirt Gillum	`Tue Apr 22 1997 16:56`	14
	Autosense (not to be confused with Autonegotiate) was removed as a console option about 2 (or is it close to 3 now??) years ago. Therefore, for the most recent versions of the driver, the autosense feature has been removed from the driver (it was more problems than it was worth -- setting specific media always seems to work). Autonegotiation is the 802.3u feature found in the DE500-AA and DE500-BA. It's a hardware approach for negotiating speed/duplex for a Ethernet connection. Current consoles (less than 2 years old) will set "Twisted-Pair" (10mbit CSMA/CD UTP) for the default if the user doesn't define anything else.