On 12/3/2023 2:19 PM, John H. Reinhardt via cctalk wrote:
On 12/3/2023 10:27 AM, Douglas Taylor via cctalk wrote:
That is my question.
I have used a couple of versions of the SCSI2SD boards in the past
with Viking, Emulex QC07, DEC RQXZ1 controllers in the past, and also
direct connections to MicroVax SCSI buss's.
There are other manufacturers of these SD to SCSI emulators now. What
is the current SOA? What works, what doesn't work with DEC hardware?
Doug
State of the Art SCSI replacement is the ZuluSCSI RP2040 which is from
the same people as SCSI2HD (I think - at least the same US Store). In
any case the SCSI2HD is generally out of stock unless there is some
NOS left. The ZuluSCSI is what is in production now.
It's under continual development with fixes and new features are being
added (for better or worse). I have two in a MicroVAX3100-95. One is
the main file systems - I have a 256GB SD card where there are 4
drives allocated. There are two 50GB main drives and 2 9GB system
drives. I have them mirrored under VMS Volume Shadowing. I aim to use
about 50% of the capacity of the SD card to allow plenty of space for
the card's firmware to do wear leveling. They are SAMSUNG PRO
Endurance cards with an estimated endurance of 140k hours. The other
ZuluSCSI RP2040 card is mounted for external access and is the backup
device. This gets rotated regularly.
All that said, in the MV3100 they are still slower by a touch than
rotating disks. But after having several Ebay SCSI disks have
controller issues (shorting and burnt out controllers) I am hoping
these are more trouble free.
I also have 2 older SCSI2HD in my AlphaServer DS10 systems for
removable storage. When I get a chance I am swapping them out for the
ZuluSCSI RP2040 models because they are slightly faster and much
easier to manage.
The ZuluSCSI is a hybrid of the SCSI2HD hardware and SCSI firmware and
the BlueSCSI management firmware. With the SCSI2HD you needed a
utility (mostly) to mange the settings of the SCSI2HD card. COpying
the data to the card usually meant using a utility like dd or
something that could write to specific places on the card. With the
ZuluSCI you format the SD card in FAT or EX-FAT (if your disks are
bigger than 4GB) and put them on the card with a specific name
format. The documentation explains it all pretty clearly.
www.zuluscsi.com - US Store and some documentation
https://github.com/ZuluSCSI/ZuluSCSI-firmware/wiki/ZuluSCSI-Manual -
Documentation
https://github.com/ZuluSCSI/ZuluSCSI-firmware - firmware
https://www.amazon.com/gp/product/B09WB3D5GQ - Samsung PRO Endurance
https://semiconductor.samsung.com/consumer-storage/memory-card/micro-sd-pro-endurance/
- marketing info
Thanks, now I know what to ask for for Christmas!
The only conflict I ever ran into was a Viking QDO would work in a
MicroVax II, but not in a PDP-11.
The other problem I ran into was when I removed the SCSI bus termination
resistor pack from a V5 SCSI2SD and forgot the orientation on how to
re-install it.
