> I ran across a DEC OBA11-VA (attached to a dual TU58 drive) while sorting
> my junk room. Anyone have a link to documentation or any information on it?
The BA11-VA was a small Q-bus enclosure with power supply.
Most often, in the "SB11' system, it enclosed an LSI-11/03 equipped with a MXV11 and sometimes extra serial lines like DLV11J and sometimes a GPIB card (IBV11?) or general purpose parallel I/O.
If yours had TU58's attached it was probably used like a small industrial/scientific controller or data logger or development system.
Sometimes they had custom applicatons burnt into the EPROM in the MXV11, other times they just used a regular bootloader and booted RT-11 from TU58 which than ran the application.
Look inside and see if you've got IBV11's or other I/O type cards.
Up through the 90's similar small desktop Q-bus chassis were sold by MTI and Andromeda for similar purposes (although by the 90's with more modern peripherals than the TU58!) I traveled with an Andromeda Q-bus system a lot in the 90's.
Tim.
--- On Wed, 7/14/10, Andrew Lynch <lynchaj at yahoo.com> wrote:
> I'll continue researching and hopefully something will turn
> up.? If any of
> our German/European colleagues have access to the PC Par
> 68000 article in
> "mc" from 1989 and would be willing to scan I would greatly
> appreciate it as
> it seems to be the most practical solution at the moment.
Weren't you the OP? I done said Radio Electronics had a series on building
a 68K box w/ISA slots. I perused the 1st installment this morning, and yep
it'll run an MDA card (CGA probably too), and stock floppy controllers, as
well as hard disk controllers. What more could you want! Keep in mind though
the original developer is on these lists somewhere, and wants big bucks for
the (more or less complete) kit. So you'll have to contact him if you want
to use his firmware. I don't have the entire set of installments, but
presumably (though don't quote me) the artwork was available right in the
magazine.
[AJL>]
Hi Chris,
Would you please tell me which Radio Electronics like year, month, had the
68K circuit. If the design is proprietary then it is probably not a usable
design. What you are describing sounds like a 68K motherboard in the PC or
AT format. My plan is to place the 68K SBC on an ISA board starting with an
ISA prototyping board. If you or someone else would please scan the article
it sounds very interesting whether it would be useful for my project or not.
I've found a good circuit with a complete schematic and description. It has
some firmware and appears complete. Also it is public domain hardware and
free (speech -- GPL) software so it is an ideal home brew project. It makes
sense to me to do a little research and select an established home brew 68K
project and use it as a base to extend to the ISA board rather than reinvent
the circuit entirely.
Thanks and have a nice day!
Andrew Lynch
On 7/19/10, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
>> market for blank diskettes and cartridges. Reminds me of the DEC Rainbow
>> (wasn't that system deliberately crippled to prevent it from being able to
>>
>> format blank media?).
>
> Only (AFIAK) by DEC not supplying a formatter program with early versions
> of the OS. The hardware was quite capable of formatting blank disks.
In the case of the Rainbow, the hardware was capable of formatting
media, but ISTR some other DEC controllers didn't have bits left over
in a CSR or didn't have enough command packet varieties to include a
media format request or some other design limitation that was left out
for various reasons, not primarily to force users to buy pre-formatted
media, but since DEC had been selling pre-formatted media for years
(RX01, RX02, RL01, RL02, TU58...) (vs older devices that *could* be
user-formatted - RK05, DECtape, etc) it was believed at the time that
users wouldn't complain enough to make a more complicated (and
expensive) solution necessary.
I think for the most part, they were right - there might have been
some grumbling about the cost of media, but commercial customers were
used to paying for places to store their bits. Home users were
another market entirely, and I don't think that it went over as
smoothly when trying to sell expensive disks to that crowd.
I remember complaints from the later RX50 era that I don't remember
>from the RX01 era vis-a-vis buying pre-formatted media. The
difference lies, I think, more with the audience than the technology
on this one.
-ethan
"Jerome H. Fine" <jhfinedp3k at compsys.to> wrote:
> >Johnny Billquist wrote:
>
>>> > >Ethan Dicks <ethan.dicks at gmail.com> wrote:
>> >
>>>> >> >On 7/14/10, Jerome H. Fine <jhfinedp3k at compsys.to> wrote:
>>> >>
>>>> >>> In addition, does anyone know of any systems currently running
>>>> >>> which support RTEM-11 features which allow RT-11 programs
>>>> >>> to run in that environment? My assumption is that VMS on a VAX
>>>> >>> supported RTEM-11 at some point, but perhaps (if I am correct)
>>>> >>> the RTEM-11 support was not continued with
>>>> >>> more recent versions of VMS on the VAX and most definitely VMS on the
>>>> >>> Alpha. Can anyone comment on these questions?
>>> >>
>>> >> Based on the vague reference at
>>> >> http://s-and-b.net/help?key=RTEM~Release_notes&title=VMS Help&referer=
>>> >> and what I know of VMS and DEC hardware, I'd think that RTEM-11 would
>>> >> require a VAX processor with "compatibility mode", i.e., a "VAX-11"
>>> >> processor. The primary models would be the 11/78x, 11/750, 11/730 and
>>> >> 11/725 (I don't recall if the VAX 86xx still had "compatibility mode"
>>> >> or not, but it should be easy to check). MicroVAXen and such did not
>>> >> have it, and Alpha processors certainly did not have it.
>>> >>
>>> >> That being said, I have no experience with RTEM-11, but I would be
>>> >> surprised to learn it ran on a machine made after about 1986 or so.
>> >
>> > RTEM might be something else than RTEM-11, which was a software
>> > product for RSX. Just google for RTEM-11, and you'll find some
>> > references for it.
>> >
>> > However, I wonder about RTEM for VAX. It's certainly possible, but I
>> > can't find any other reference to it, and DEC's old SPDs, especially
>> > those with software version compatiblity matrixes, are usually pretty
>> > good as a way of finding out what software existed.
>> >
>> > As for PDP-11 compatibility in VAXen, yes, the 86x0 machines have
>> > that. Those were the last, however.
>> >
>> > For all other VAXen running VMS, if you wanted to run RSX software,
>> > you needed a PDP-11 emulator product for VMS, which was available, in
>> > addition to the RSX additions for VMS, which was also a separate
>> > product. That thing was supported up until fairly recently, though.
>> > But again, that's for RSX stuff...
>
> I suspect that the most likely possibility is that RTEM and RTEM-11 are
> used.
Huh? If you are suggesting that they would be the same, I can assure you
they could not.
A very common misconception these days seems to be that VAXen with PDP-1
compatibility could run PDP-11 programs. That is only true in a very
limited sense. Only the basic PDP-11 instruction set is supported by the
VAX, and only the user mode stuff. EMTs, as well as any other kind of
traps, interrupts, and so on, was *not* supported.
When you execute an EMT in PDP-11 mode on a VAX, it will trap back to
VAX mode. No possibility to have a PDP-11 trap handler.
> In addition, I also suspect that both Johnny and Ethan are correct in
> that RTEM
> was supported under both RSX and VMS on an older VAX which allowed
> compatibility mode.
It would have to be totally separate products in that case.
> I don''t know if Megan Gentry is still around or perhaps Allison or one
> of the
> other DEC fellows. Perhaps they might at least know something about which
> hardware and operating system(s) supported RTEM?
I definitely remember (and probably still have some mail somewhere) from
Megan mentioning that she used RTEM-11 for RT-11 work, running on RSX
machines. Possibly even an 11/74.
> In addition, RSTS/E also supported RT-11 programs via the SWITCH RT11
> capability. However, only the RT-11 EMTs which are used by a SJ are
> supported
> by RSTS/E. At least there is quite reasonable documentation as well as
> the ability
> to test and actually run RT-11 programs under RSTS/E up to the latest
> versions
> of RSTS/E. RT-11 EMTs for mapped RT-11 monitors (RT11XM) are not supported
> not are multi-terminal EMTs. Also, probably the latest RT-11 EMTs for
> file status
> information are also not supported under RSTS/E.
The correct technical term is that RSTS/E have a RT-11 *run time
system*. An RTS in RSTS/E provides an environment under which you can
get a specific behaviour. So you had RTSes for RT-11, RSX, BASIC+, TECO,
DCL and some other stuff. Some RTSes were also KBMs (keyboard monitors),
meaning you could "switch" to them, and get an interactive command line
interpreter with that. But the RTS mostly implemented system calls.
However, there were RTSes which didn't implement any system calls, and
only gave you the basic calls RSTS/E itself provided, and mostly focused
on being a KBM, such as DCL.
You can write you own RTS if you want to, and one think that have been
at the back of my mind is if it wouldn't be pretty easy to write a Unix
RTS for RSTS/E, so that you can run a bunch of Unix binaries under
RSTS/E as well.
All exeutable files have an RTS associated with it, and when the program
is run, it is run under that RTS, which then handles all EMTs and so on
when the program executes them.
> Probably in the same manner as RSTS/E, if RTEM is supported under VMS on an
> older VAX, the most likely only the RT-11 EMTs which are used by a SJ are
> supported.
Yes, RTEM-11 would most likely just provide a simple RT-11 environment,
such as SJ. As I said before, I can't really find any proper information
about any RT11 environment for VMS... But if it existed, it would
probably be just SJ as well.
Johnny
personally I love old monitors. This ones seems especially instersting being it has BNC jacks.
I'd stick it in the closet, or in the yard inside 2 or 3 very sturdy plastic bags. If Adrian gets his way, there won't be a single one left in the entire UK!
> From: Steven Hirsch <snhirsch at gmail.com>
> Subject: Amlyn Minipac diskette changer
>
> Has anyone else on the list seen one of these? I picked up a Vista V1200
> disk system for Apple 2 that uses this type of drive. The mechanism takes
> a plastic cartridge with five 5.25" floppy disks. The diskettes appear to
> be conventional SS format with a couple of extra punchouts to mate with
> the loader mechanism. Electrical interface is compatible with 8" floppy
> drives (interface card was also sold for that purpose).
>
> I'm not able to turn up any information about the drive and am wondering
> how the diskette select/load scheme is intended to work. There are
> at least a couple of possibilities:
>
> - Treat the physical diskettes as portions of a single logical floppy and
> select diskette by track range (first diskette 0-39, second 40-79, etc.)
>
> - Treat each physical diskette as a logical drive and use binary select
> lines on interface to choose.
>
> Anyone have documentation on the drive mechanism or the Vista product?
I had a very similar unit for the Apple 3. As I remember it looked like a single 6MB drive to the OS. I don't think that would have been possible on Apple 2. Earlier I had a 5MB ICE hard drive on an Apple 2 which looked like 35 floppy disks to DOS. It might have looked different under UCSD Pascal, maybe you could have a single large file, but its a long time ago, I just can't remember.