Here is an O2 with a dual-channel Adaptec 3940UW SCSI card, made possible by modifying the
adp78.o kernel file in /var/sysgen/boot. The replacement file is now available on my Depot Resources
page for download (backup the original somewhere before installing the new file).
Code: Select all
CPU: MIPS R5000 Processor Chip Revision: 10.0
FPU: MIPS R5000 Floating Point Coprocessor Revision: 10.0
1 300 MHZ IP32 Processor
Main memory size: 256 Mbytes
Secondary unified instruction/data cache size: 1 Mbyte on Processor 0
Instruction cache size: 32 Kbytes
Data cache size: 32 Kbytes
FLASH PROM version 4.18
Integral SCSI controller 0: Version ADAPTEC 7880
Disk drive: unit 1 on SCSI controller 0 (unit 1)
CDROM: unit 4 on SCSI controller 0
Integral SCSI controller 1: Version ADAPTEC 7880
PCI SCSI controller 3: Version ADAPTEC 7880
PCI SCSI controller 4: Version ADAPTEC 7880
On-board serial ports: tty1
On-board serial ports: tty2
On-board EPP/ECP parallel port
CRM graphics installed
Integral Ethernet: ec0, version 1
Iris Audio Processor: version A3 revision 0
PCI Adapter ID (vendor 0x9004, device 0x8078) PCI slot 1
PCI Adapter ID (vendor 0x9004, device 0x8078) PCI slot 2
PCI Adapter ID (vendor 0x1011, device 0x0001) PCI slot 3
PCI Adapter ID (vendor 0x9004, device 0x8278) PCI slot 4
PCI Adapter ID (vendor 0x9004, device 0x8278) PCI slot 5
Video: MVP unit 0 version 1.4
with no AV Card or Camera.
Vice: TRE
By default the Adaptec card only has one of its channels presented externally, so to make use of it one could
simply route a cable from the other channel to an external socket rigged to fit in the slot normally occupied by
the 1600SW adapter or dual-head board, or one could cut the casing in some other manner. Using a simple
cable extender, I found that for an R5K system I had to cut away one of the thin metal strips from the edge
of the PCI tray (this is easy to do, just wobble it bac & forth with a pair of pliers and it will fall off), while for
an R10K system I didn't need to make any changes, though routing the cable must be done carefully so as not
to impede the cooling of the CPU.
Either way, this is a simple method of having better disk I/O, ie. three external channels for storage.
A warning though: be careful about buying a 3940 card as some of the ones advertised are not what
they seem, usually misdescribed by sellers. The card should look like this.
Cheers!
Ian.