Subject: Re: Netbooting uVAX II
To: Greg Ingram <>
From: Nigel and Delores Johnson <>
List: port-vax
Date: 06/21/1999 13:10:22
1)    Use a packet sniffer as others have suggested

2)    Try to read the little label on the prom that gives it its address.
Usually lost at this stage in the game.

3)    Do what I do (old CE trick)  examine the registers.  The address is

The DEQNA is usually at 17774440 octal.  You can read the ethernet address
here.  If yours is there, do the following:  I'll give you an example from one
of mine.  My MAC address is 08002B029707 (0800 indicates DEC MFR)


>>> e/p 20001920
    p  20001920  FF00FF08
>>> e
    p  20001924  FF02FF2B
>>> e
    p  20001928  FF07FF97

Ignore the FF's

Read the complete bytes from right to left staring at 1920:

FF00FF08 becomes  0800
FF02FF2B becomes 2B02
FF07FF97 becomes  9707

There you have the hardware address encoded in PROM!1

To convert a device from octal (PDP qbus) to HEX MVII Qbus)  do the following:

subtract 17760000
convert to hex
ad 2000000 hex.

The standard alternate address is 17774460.  ==>   14460   ==> 0x1930  ==>

Hope this helps


Nigel Johnson

Greg Ingram wrote:

> Okay, I've now got a working serial console.  Now I'm trying to netboot
> this beast.  From the (somewhat outdated?) netbooting HOWTO, it seems that
> I need to know my ethernet address.  The HOWTO lists two possibilities,
> neither of which seems to work on the uVAX II.  Or perhaps it's that the
> DEQNA needs a different command.
> Anybody know how to get the ethernet address from either the >>> prompt or
> from VMS 4.2?
> Thanks,
> - Greg