Greetings folks.  I just took the time to inventory all the major chips on
my Magnum 4000SC motherboard.  I'm hoping this will help to get things working!
Most interestingly, I do *not* have a 4030, 4230, or a uPD31432 I/O Controller.
I'm *guessing* that my I/O Controller is the LSI Logic/MIPS L1A7385, since
everything else is accounted for.  It is to the direct upper left of the CPU
and seems to be the best candidate.  Unfortunately, I have been unable to
find any information about this chip at all.
I'm hoping someone on the list knows!  Also, I find it most curious that the
serial controller uses an 8MHz xtal, NOT an 8.192MHz xtal.  Curious that my
serial console is working with NetBSD, since I have 8.192 in the kernel config
file.  Strange!

Here goes the IC list...  Enjoy!
-Mark

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Motherboard ID
ASSY No. 030-0350-061 Rev. A
Serial # G4892

CPU
MIPS R4000SC + 50MHz xtal
4-hole "J2" jumper, empty

DRAM Controller?
Toshiba TC85R4220F x 2

I/O Controller?
LSI Logic/MIPS L1A7385 (32-00094)

L2 Cache RAM
Toshiba TC551664J-15 x 11

SCSI Controller
Emulex FAS216 + 40MHz xtal

Serial Controller
Western Digital Corp. WD16C552-JT + 8MHz xtal
2-pin "J4" jumper, empty

Floppy Controller
Intel/NEC N82077AA + 24MHz xtal

SONIC Ethernet Controller
NatSemi DP83932BVF + 20MHz xtal

???
4.096MHz xtal
center of motherboard

EISA Bus Controller
Intel NG82358-33

EISA Integrated System Peripheral (ISP)
Intel NG82357

EISA Bus Buffer (EBB)
Intel S82352 x 2

EISA/ISA bus reference frequency?
14.31818MHz xtal

Firmware Flash
American MicroDevices AM28F020

Real Time Clock
Dallas DS1287

Non-Volatile SRAM
Dallas DS1225Y-200

???
American MicroDevices EPROM w/sticker "50-00534-003" "C99A"

???
Unknown PLCC w/sticker "W5" "INTPND" "5000" "496" "499D"
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