Megan wrote:
>Zane wrote:
>>Actually you've got me thinking there. Considering that RAM is dirt
>>cheap these days. I'm wondering what it would take to build a RL02 drive
>>that is actually a RAM disk (of course you'd be able to fit several disks
>>on one stick of RAM), and what kind of performance you'd get. Off course
>>I'm not a hardware type, so I don't know how hard that would be.
>
>Hmmm... don't the MS630/MS650 boards simply get power from the bus,
>and memory transactions are over the PMI cable? If so, then what
>about some sort of Qbus option which looks like a disk, but has a
>connector on it so that it connects to the MS6xx board... ready-made
>memory farm which could be used as a disk... (And don't some of the
>boards come in 16mb and 32mb flavors?)
I think this is more or less what Jerome was looking for. IIRC, you're
right about the boards only getting power from the Q-Bus. One problem I
see is you might be limited to what slots the boards can go it.
MS630's came as 1,2,4, and 8MB boards, and MS650's came as 8MB or 16MB.
MS630's and MS650's weren't interchangable on the VAXen, so might not be
mixable for something like this. I believe there were 16MB 3rd party MS630
equivalents, and 32MB MS650 equivalents, but am not possitive.
What I'd been suggesting is a board with a single DIMM slot that you could
go out and buy 64,128, or 256MB and slap it in. Have some sort of battery
backup and you're good to go. Though this might actually need to be in an
external box. For the maximum usefulness you'd have it in a box, and
simply plug it into an RL02 Controller. For maximum usefulness have a
switch that'll allow you to save the memory image to a EIDE HD. Of course
since an EIDE disk would be able to saturate the Q-Bus....
Anyone have any idea how hard it would be to build a box with a DIMM in it
that looked like an RL02?
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh_at_aracnet.com (primary) | OpenVMS Enthusiast |
| healyzh_at_holonet.net (alternate) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
Received on Sat Feb 03 2001 - 22:49:22 GMT