Roland synth to hard-drive connection .
fffcj
It has two connectors for a scsi hard-drive .
One is a 25pin female D socket , labelled ' scsi A ' .
The other is a female 50 'pin' Centronics , labelled ' scsi B' .
All I need is 10 Gigs of storage .
Speed is unimportant .
There are many plugs and sockets in the scsi world , which I find
baffling .
I will have to order a cable to connect my scsi drive .
Do the pin conformations have to match those on the rear of the
synth ?
I note there are some cheap used scsi drives , ex server , on Ebay .
Might one of these old drives suit me ?
Can I get a cable from my 50 pin Centronics which will connect to the
drive , even if it uses a quite different pin count and socket .
Thanks
Chris
Michael Baeuerle
>
> I have a VP9000 Roland synth .
> It has two connectors for a scsi hard-drive .
> One is a 25pin female D socket , labelled ' scsi A ' .
> The other is a female 50 'pin' Centronics , labelled ' scsi B' .
> All I need is 10 Gigs of storage .
Hmm, the VP9000 compatibility guide [1] say:
|
| Most SCSI and SCSI II hard drives work with the VP-9000
| and can be formatted up to 2.1 GB per drive.
Looking at [2], chapter 10 shows that this is a limitation of the MS-DOS
FAT16 filesystem [3] used by the VP9000 operating system and has nothing
to do with the SCSI subsystem.
Looks like for 10GByte you need 5 disks because multiple filesystems on
one drive are not supported. A way out my be an update of the MS-DOS on
the VP9000 to at least Version 7.0 and a FAT32 filesystem.
> Speed is unimportant .
> There are many plugs and sockets in the scsi world , which I find
> baffling .
> I will have to order a cable to connect my scsi drive .
> Do the pin conformations have to match those on the rear of the
> synth ?
Look at [2], chapter 1 for information about the VP9000 SCSI interface.
You can see that the VP9000 internally has only one SCSI port and both
connectors are connected together. This allows you to use the VP9000 in
the middle of a SCSI chain (with the SCSI bus routed "through" it).
Because of this, both connectors are equivalent and you can use one, the
other or both simultaneously.
As with any parallel SCSI bus, both ends must be terminated. The VP9000
has an internal terminator that can be activated with a switch. You have
to activate it if you use the VP9000 at the end of a SCSI chain (one of
the 2 connectors is unused) and you have to deactivate it if the VP9000
is located in the middle of the chain (both connectors are used).
> I note there are some cheap used scsi drives , ex server , on Ebay .
> Might one of these old drives suit me ?
Very likely. Your VP9000 has a single ended (SE) interface that is
compatible with most SCSI hard disks. The oldest ones have SE interfaces
and the newest ones have LVD/SE multimode interfaces, they should all be
compatible with your VP9000 on the SCSI level. I don't know what the
VP9000 will do if you connect a disk with a capacity >2.1GByte, but even
then you can limit the reported capacity of newer disks (requires a PC
with SCSI hostadapter).
The only disks that are incompatible with the VP9000 are the rare ones
with high voltage differential (HVD) interface. They were mainly used in
expensive server systems before the LVD/SE multimode interface was
available.
If you search for naked disks, look that they have a connector for
cables (50pin or 68pin). Disks with backplane connector (80pin "SCA")
can be used too, but you need an additional adapter for them. Mount the
disk in a SCSI enclosure with power supply and matching SCSI connectors
(50pin or 68pin respectively).
> Can I get a cable from my 50 pin Centronics which will connect to the
> drive , even if it uses a quite different pin count and socket .
In general: Yes.
Your VP9000 has a so called narrow SCSI interface with 8Bit data bus.
Devices with wide SCSI (16Bit data bus) are compatible as long as the
unused lines can see at least one terminator so that they don't float.
The following bus layout is allowed and will work:
- VP9000 terminator active (first end of bus)
One connector on VP9000 must now be open/unused!
- Cable from other connector of VP9000 to disk enclosure
(say 50pin Centronics to 68pin HighDensity)
- Disk with wide SCSI interface on 68pin connector and disabled
or nonexistant onboard terminator
- Wide SCSI terminator on the second connector of the disk enclosure
(second end of bus)
If the disk has an onboard terminator, you have the choice: Do it as
specified above or activate the onboard terminator of the disk and leave
the second connector on the enclosure open/unused (same as on the other
bus end at the VP9000).
The maximum allowed length of the SCSI bus (from one terminator the the
other) is 6m, not 6.5m as specified in [2]. If you want to use cheap
cables, make the bus as short as possible because such cables are often
not fully SCSI compliant.
Micha
[1] http://cms.rolandus.com/assets/media/pdf/VP9KComp.pdf
[2] http://media.rolandus.com/manuals/VP-9000_OM.pdf
[3] http://en.wikipedia.org/wiki/File_Allocation_Table
fffcj
I guess I might try to partition a 10Gig drive into five fat16 2Gig
partitions .
The VP9000 can't do this , I should think .
So I would need a scsi card for my pc to conduct this partitioning and
formatting .
Possible ?
Thanks
Chris
Robert Heller
Sure. SCSI cards are available cheap from E-Bay. Get an Adaptec 2940
-- these are well supported by all PC O/Ss.
>
> Thanks
> Chris
>
--
Robert Heller -- 978-544-6933
Deepwoods Software -- Download the Model Railroad System
http://www.deepsoft.com/ -- Binaries for Linux and MS-Windows
hel...@deepsoft.com -- http://www.deepsoft.com/ModelRailroadSystem/
edfair
External SCSI drives normally mount into external cases which are
generally equipped with 50 pin amphenol (centronics) connectors at the
age you are talking about and those lead to 50 connector IDH to match
the 50 pin connector on the back of the drive. From you description you
could use either the D25P to 50 centronics cable or the 50 centronics to
50 centronics cable.
Later cases throw in other options for cabling but since you are at 2.1
gb max drives the earlier types would be what you would use.
I would suspect that the synth has the 50 pin connector in order to use
an external terminator.
Most external cases have 2 connectors also, in order to daisy chain
devices or to use a terminator.
The 50 pin SCSI or SCSI II drives were becoming scarcer on ebay the
last time I looked and the prices were rising to reflect that
scaricity.
So far as an external case, I've used a bunch of external 5" SCSI tape
cases for my drives by using a 5 to 3 drive kit, but you have to be
careful and get a kit that has the capability of bottom screws.
Michael Baeuerle
>
> The 50 pin SCSI or SCSI II drives were becoming scarcer on ebay the
> last time I looked and the prices were rising to reflect that
> scaricity.
It is very likely that SCSI3 drives will work too. And if partitioning
on a PC really allows to use multiple 2GiByte filesystems, why not use a
newer drive? The desired capacity is 10GByte, SCSI drives usually are 9
or 18GBytes. In this capacity range, wide SCSI was not rare. If he can
get his hands on such a disk for a good price, there is no reason to
reject it only because "not 50 pin".
Another hint for Chris: For drives from Seagate you can extract the
interface from the letters after the model number.
What you want is one of the following:
----------------------------------------------------------------------
STxxxxN Narrow SE, 50 pin
STxxxxW Wide SE, 68 pin
STxxxxLW Wide LVD/SE, 68 pin
----------------------------------------------------------------------
What you can use, but only with an additional adapter:
----------------------------------------------------------------------
STxxxxNC Narrow SE, 80 pin
STxxxxWC Wide SE, 80 pin
STxxxxLC Wide LVD/SE, 80 pin
----------------------------------------------------------------------
What you don't want, because it can't work at the VP9000:
----------------------------------------------------------------------
STxxxxND Narrow HVD, 50 pin
STxxxxWD Wide HVD, 68 pin
STxxxxDC Wide HVD, 80 pin
STxxxxFC Fiber Channel
----------------------------------------------------------------------
Micha