Hi All,
Thanks to Glen I now have info on my A&J Microdrive. On another
note, I have just received in today a Stringy floppy for the Commodore
64. This unit is brand new and has a brand new tape. It connects up
to the cassette port. Though I won't have time to test the units (the
wife calls it play) until thursday, at which time I will declare it
"Stringy Floppy day".
Anyway, anyone have experience with a stringy floppy for a
commodore? It's called a "Quick Data Drive".
Thanks
Rob
(self appointed king of the string)
(just kidding)
Robert Borsuk - rborsuk(a)colourfull.com
President
Colourfull Creations
http://www.colourfull.com
Wouldn't 'narrow' SCSI cabling work inside? The only real problem then
would be termination...
Cheers...
Ed Tillman
Store Automation Tech Support Specialiost
Valero Energy Corporation
San Antonio, Texas, USA
Office: (210)592-3110, Fax (210)592-2048
Email: edward.tillman(a)valero.com <mailto:edward.tillman@valero.com>
-----Original Message-----
From: Megan [mailto:mbg@theworld.com]
Sent: Wednesday, March 05, 2003 12:12 AM
To: cctalk(a)classiccmp.org
Subject: RE: DEC RD54 from Maxtor
>> Yes, going to SCSI would be nice, but you can't put one in
>> your VAXstation 2000...
>
>Unless you use Wolfgang Moeller's modified ROMs - then I believe
>that SCSI will work. (IIRC the modified VS/UV2K ROMs also
>incoroporate the >1GB fix ... but it's been a long time since
>I looked).
I know the disk would fit, and I know it can talk SCSI, but I
didn't know whether the SCSI cabling for the disk would fit
inside the VS2000 box... That's all I meant.
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | email: mbg at world.std.com |
| | |
| "this space | (s/ at /@/) |
| unavoidably left blank" | URL: http://world.std.com/~mbg/ |
| | "pdp-11 programmer - some assembler |
| (DEC '77-'98) | required." - mbg KB1FCA |
+--------------------------------+-------------------------------------+
>It does look like ODS-2 and RT-11 FS cannot co-exist, however,
>since they both want to use the 64 blocks at the start of
>the image, unless it's possible that the unnecessary fields in
>each of those two formats can be persuaded to step out
>of each others way. Do you have any details about exactly
>what RT-11 requires in that area? Maybe a disk that boots
>on PDP-11, VAX (VMS), Alpha (VMS) and PC is possible
>after all :-)
RT absolutely needs block 1, the Home Block. If you want the
disk bootable, then 2-5 are absolutely required. Typically,
blocks 6 through 6+(2*31)-1 are required for the directory,
but the home block contains a value where the directory is
supposed to start... but I don't believe that RT actually
uses this field, and many utilities certainly don't, assuming
the directory starts in block 6 (not to mention user programs).
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | email: mbg at world.std.com |
| | |
| "this space | (s/ at /@/) |
| unavoidably left blank" | URL: http://world.std.com/~mbg/ |
| | "pdp-11 programmer - some assembler |
| (DEC '77-'98) | required." - mbg KB1FCA |
+--------------------------------+-------------------------------------+
BTW Rob, which model TS computer are you using the A&J with?
Later --
Glen
0/0
> Hi All,
> Thanks to Glen I now have info on my A&J Microdrive. On another
> note, I have just received in today a Stringy floppy for the Commodore
> 64. This unit is brand new and has a brand new tape. It connects up
> to the cassette port. Though I won't have time to test the units (the
> wife calls it play) until thursday, at which time I will declare it
> "Stringy Floppy day".
> Anyway, anyone have experience with a stringy floppy for a
> commodore? It's called a "Quick Data Drive".
>
> Thanks
> Rob
> (self appointed king of the string)
> (just kidding)
>
>
> Robert Borsuk - rborsuk(a)colourfull.com
> President
> Colourfull Creations
> http://www.colourfull.com
I don't know how many people might be interested, but I have finally
been successful in creating a Bootable RT-11 CD which also has
the standard ISO file structure. However, the really key point is
that none of the files on the CD are duplicated.
On the other hand, I am unable to test the CD that I just burned
using real DEC PDP-11 hardware since I have never tried very
hard to find and successfully test a CD-ROM drive with a SCSI
host adapter on the Qbus PDP-11 which is available for such
purposes. But, using the Full Commercial Ersatz-11 running
under Windows 98 SE, I just did the commands:
MOUNT DU0: SCSI0:
BOOT DU0:
I assume that if I had a suitable real DEC PDP-11 system with
a SCSI CD-ROM drive, the exercise would work there as well
since I know that others have been successful with an RT-11
ONLY CD that boots on real DEC PDP-11 hardware.
Since many of you reading this who don't know much about RT-11
will likely be confused, let me describe very briefly how I started.
I first took 4 RT-11 RL02 bootable images or DSK files, each being
20450 blocks long. Since only the first 5000 to 6000 blocks of each
file contained useful non-zero information, I reduced each image to the
size that did not contain any blocks with all zeros so that all 4 RL02
images would fit into a single RT-11 partitions of 65536 blocks. I
then
used Nero Burning under Windows 98 SE to copy all 4 RL02 images
to a CD which had the standard ISO file structure after which I copied
24612 blocks from the CD-RW to a file under Windows 98 SE:
Blocks 0 to 63 - All zeros
Blocks 64 to 99 - Standard ISO file structure
Blocks 100 to 24599 - The 4 files
Blocks 24600 to 24603 - Extra information for the standard ISO file
structure
Blocks 24604 to 24611 - All zeros
The first file from block 100 to block 5192 was the RL02 bootable
image for V5.03 of RT-11.
There is one technical problem I have not solved - the current
test was done with a CD with an image that is identical to a
file of 24612 decimal blocks - which is less than one full RT-11
partition. If I am going to be able to use a CD with more than
65536 decimal blocks of files (i.e. more than one full RT-11
partition), I will have to solve one critical problem. I must find
a method of preventing any files under the standard ISO file
structure from using any CD sectors that fall in the first 16 that
start on a multiple of 16384 sectors (of 2048 bytes which is
how a CD is written for those users who might not know).
These number correspond to the first 64 blocks that start on
a multiple of 65536 blocks (of 512 bytes) on a hard disk drive
which corresponds to each RT-11 partition.
Before I describe the details, note that the method is probably
useful ONLY when the CD contains a limited number of large
files. This is because the RT-11 directory on the CD must be
mostly constructed by hand at the present time.
The first step is to create an exact copy of a CD which has been
burned with the desired DSK files. This image file can be
created using PUTR to specify the exact size plus E11 and RT-11
to copy all the blocks from the CD to the image file.
The critical reason that everything works seems to be a rather
fortunate use of the mutually exclusive areas by the RT-11 file
structure and the standard ISO file structure. While RT-11
requires the first 64 blocks (of 512 bytes) for the boot blocks
and file structure, the standard ISO file structure uses the next
9 sectors from sector 16 to sector 24 (of 2048 bytes) which
allows the RT-11 DSK files to start at block number 100 or
sector number 25. All that is required (from the RT-11 file
structure for the RT-11 DSK file that is in the first RT-11
partition) is to copy the RT-11 file structure (ONLY - i.e. just
blocks zero to where the directory segments stop) to the start
of the image file (which is initially identical to the ISO file
structure CD image with the DSK files placed on the CD
using standard CD burning software - in my case I used
Nero Burning on a CD-RW so that I need not toss the CD).
I produced that image file by using E11 and RT-11 to copy
the CD-RW image to an existing file under Windows 98 SE.
In my test, since I chose the first DSK file which started at
block 100, the next step was to add 100 to the starting block
number in each directory segment. The final step was to then
select the monitor that I wanted to boot and write the correct
boot programs into block zero and 2 through 5 of the image
file. All of the extra steps were easily accomplished using
E11 and RT-11.
The following summary probably helps:
RT-11 file structure: Blocks 0 to 63, Sectors 0 to 15
ISO file structure: Blocks 64 to 99, Sectors 16 to 24
RT-11 files: Blocks 100 to 65535 for partition zero
ISO files: Sectors 25 to end of CD
To create an RT-11 bootable CD, I copied the original CD
image to a Windows 98 SE file on the hard disk. I then copied
did an INIT DU0:/VOLUME under RT-11 after which is copied
blocks 106, 107, 108, 109, 110 and 111 to blocks 6,7,8,9,10,11.
The SIPP was used to add 100 (144 octal) to the fifth word in
blocks 6, 8 and 10. The last step was to use the RT-11 command
COPY/BOOT DU0:RT11XM.SYS DU0:
I then had to use the "Burn Image" option under Nero Burning to
transfer the complete file back to the CD (after I had erased the files
of course) since I do not have any software to write just the first
3 CD sectors.
One other aspect is also permitted under RT-11. Since every
RT-11 directory segment contains the starting block number
in the fifth word, it is possible to have the ISO file that is a
bootable RT-11 image of some device referenced both by
each file AND as a single DSK file starting with a new directory
segment at the end of all the individual files. In my actual test
example, there were FOUR bootable DSK files under the ISO
file structure (within RT-11 partition zero). The first 3 RT-11
directory segments (starting in block 6 of the CD) contained
file headers for 206 files. An additional directory segment was
then added (manually one word at a time with SIPP) which
had an empty area starting at block 100 with sufficient space
for the FOUR bootable DSK files. CREATE was then used
to set up the file headers one at a time. Obviously RT-11
is being "fooled", but it does work!
The net result is that it is possible to use the same files under
BOTH the standard ISO file structure AND the RT-11 file
structure.
While all of the above was done on a Pentium system running
Windows 98 SE, Nero Burning, Ersatz-11, PUTR and RT-11,
I am confident that other operating systems and software
utilities would also be successful. The actual concepts are
really very simple. Implementation of the test case did take
almost a week since I made a lot of mistakes along the way.
But at this point, I could duplicate a second test in a few hours.
If there are any questions, I will be glad to answer them.
I do have one request. Does anyone know how or if it might be
possible to write a program that can take the image of the CD
after it is copied to a file on the hard disk and copy all the data
to a second slightly bigger file. The key requirement would be
that the blocks at multiples of 65536 (where RT-11 partitions
start - actually 64 blocks in each of the 20 possible RT-11
partitions) would be left empty. I would imagine that a simple
FORTRAN program could do this if the ISO file structure is
known since all that would be required would be to change
those parameters which specify the sector number where the
file starts - AND move the associated file up in the CD image
in the destination file so that 16 sectors starting at multiples of
16384 sectors are left empty.
Sincerely yours,
Jerome Fine
--
If you attempted to send a reply and the original e-mail
address has been discontinued due a high volume of junk
e-mail, then the semi-permanent e-mail address can be
obtained by replacing the four characters preceding the
'at' with the four digits of the current year.
I was able to pick up a copy of Windows 1.0 in the box for $2.50 and got a
Tomy OMNIBOT 2000 for $7.50. Also got Videcom terminal without the keyboard.
:-(
Hello again,
I've got a Sinclair (well, Amstrad really, but it has Sinclair printed on
the front) monitor here, which claims to be a QL monitor. To the extent
that it has a captive QL-specific signal lead...
However, the display is too wide, and marginally extends past the bezel in
both directions; only by about 1/4 of one character or so, but just enough
to be seriously annoying.
So, today, I whizzed the back off to adjust it - but there's no "horizontal
size" pot :( There are trimpots for V.size, H.hold and Sub-bright. There's
adjusters for focus & brightness (or maybe contrast, it was hard to tell
since it was simply labelled "Screen". There's also externally accessible
controls for V.hold, brightness & contrast. On the back of the tube,
there's trimpots to adjust red & blue intensity (with two pots per colour).
It looks like there ought to be a green pot as well, but there's no trimmer
there, just a fixed resistor.
So, is it the case that I cannot adjust the h.size? Is it a case of go
rooting around looking for the component (a resistor, I assume) which sets
this, and replace it with a pot?
Any advice appreciated.
--
Cheers, Ade.
Be where it's at, B-Racing!
http://b-racing.com
Thanks, everyone for your suggestions regarding SCSI controller for RT-11,
DECserver in Kansas City, etc. All of this is leading up to me building a
PDP-11 SOMETHING out of parts I can afford.
I've worked with Mike McFadden and he bought the rack of equipment containing
the terminal server and is selling me the CPU board;
Thanks to Jonathan telling me about the auction, I bid on and won the "LSI-11
Box Blow Out" on eBay PLUS the QBUS chassis (sold separately); Watch for me to
announce the availability of the 11/23 CPU's and other boards from this
auction. Hopefully the sale of some of these things will defray some of the
expense of the construction of the PDP-11.
I already have a pair of SSSD 8" floppy drives I bought to use with E-11 and
PUTR to copy from my PC to RT-11 RX01 floppies - now I need to buy the adapter
board from John Wilson to connect the big floppy's to my old 486.
I have a DECserver 550 with its CPU and CXA16's; I may use the chassis and the
CPU, or just the one from Mike McFadden. Then again, I have enough stuff now
that I could build two systems.
I have a RQDX3 and RX50 for a floppy interface to the prospective PDP-11. I'll
use one of the drives from the "Blow Out" in the new system. The chassis I
bought in the "Blow Out" has a foundation module with disk controller, etc. on
it, so I may not need these items.
I have 2 Ethernet controllers, the one from my original DECserver 550 and a
DEQNA I recently bought. One of these is likely to go.
It seems to me I am almost set - all I have to do is get all the stuff here
and set it up :-) that should be a SNAP - right? Lets see - ~1978 to 2003 is
how many years old this stuff is??? Only 25 or so. Should be no problem <g>.
Regards,
Stuart Johnson
