Greetings.  Michael Kato was kind enough to build me a 1.5_ALPHA2 kernel that
can fit on a floppy, so I was able to try booting my Magnum 4000SC.
Unfortunately it panics very early in the boot process.  What now???
Console output follows:

BIOS Vendor  ID [MIPS MAG]                                                      
BIOS Product ID [ffffff90:00:6b:ffffff82:ffffff90:34:00:ffffffbc]               
A:\NETBSD                                                                       
BIOS Vendor  ID [MIPS MAG]                                                      
BIOS Product ID [ffffff90:00:6b:ffffff82:ffffff90:34:00:ffffffbc]               
BIOS System ID [Microsoft-Jazz]                                                 
Copyright (c) 1996, 1997, 1998, 1999, 2000                                      
    The NetBSD Foundation, Inc.  All rights reserved.                           
Copyright (c) 1982, 1986, 1989, 1991, 1993                                      
    The Regents of the University of California.  All rights reserved.          
                                                                                
NetBSD 1.5_ALPHA2 (M701) #5: Tue Sep 26 23:40:30 PDT 2000                       
    mk2s@oli:/usr/src/sys/arch/arc/compile/M701                                 
MIPS Magnum                                                                     
total memory = 65536 KB                                                         
avail memory = 56972 KB                                                         
using 844 buffers containing 3376 KB of memory                                  
mainbus0 (root)                                                                 
cpu0 at mainbus0: MIPS R4000 CPU (0x430) Rev. 3.0 with MIPS R4010 FPC Rev. 0.0  cpu0: L1 cache: 8KB/16B instruction, 8KB/16B data, direct mapped                
cpu0: L2 cache: unknown size/16B mixed, no snooping                             
L2 cache line size = 16                                                         
Please fix implementation of mips3_*Flush*Cache                                 
syncing disks... done                                                           
trap: address error (load or I-fetch) in kernel mode                            
status=0x2000ff02, cause=0xc010, epc=0x802fb620, vaddr=0xfffffffe               
pid=0 cmd=swapper usp=0x0 ksp=0x8034ccc0                                        
Stopped in swapper at   0x802fb620:     lw      t1,0(v0)                        
db> t                                                                           
802fb610+10 (8033b7e0,20,16ddfa,0) ra 802f48c8 sz 56                            
802f4828+a0 (8,20,16ddfa,0) ra 802ed470 sz 24                                   802ed060+410 (8,20,16ddfa,0) ra 802f7d3c sz 40                                  
802f7d1c+20 (8,20,16ddfa,0) ra 8022e480 sz 24                                   
8022e12c+354 (c0008f00,20,8034ce40,802f7c80) ra 8022e008 sz 72                  
8022dfc0+48 (c0008f00,20,8034ce40,802f7c80) ra 802f7b30 sz 32                   
802f7a90+a0 (c0008f00,20,8034ce40,802f7c80) ra 8022e480 sz 48                   
8022e12c+354 (0,20,803195b0,0) ra 8022e0b0 sz 72                                
8022e058+58 (0,20,803195b0,0) ra 802f1b50 sz 32                                 
802f1b30+20 (0,20,803195b0,0) ra 8022dd60 sz 24                                 
8022dd10+50 (0,20,803195b0,0) ra 80216a48 sz 24                                 
main+448 (0,20,803195b0,0) ra 80200084 sz 88                                    
User-level: pid 0                                                               
db>    

Any help is much appreciated.

Cheers,
-Mark