On 2001-04-24 classiccmp(a)classiccmp.org said to kees.stravers(a)iae.nl
>You can bet there's a collector who is trying to get one of every
>model of DEC storage device or something who will want an RRD40.
>-tony
I have one and I am very happy with it. Why people are talking bad about
it I can't understand. Sure it isn't fast and has a strange caddy, but
it is _very_ reliable IMHO. Once the disk is in, you won't get any read
errors or timeouts or some such. I have installed operating systems on
several VAXstation 3100s with other SCSI drives and with the RRD40, but
while with other old non-DEC SCSI drives I sooner or later always got read
errors or timeouts, installing with my RRD40 always worked first time
without problems.
And don't forget it is one of the very first CDROM drives ever. DEC was a
very early adopter of the CDROM technology developed by Philips. The CDROM
mechanism inside the RRD40 is the first 5.25 form factor drive made. The
caddy system was used because of that form, the box was too full to add
a motorized drawer. The first drive after it that had a drawer instead
of the caddy did not have a motor, you had to pull out the drawer by hand.
Please cut the RRD40 a little slack. It is amazing it still works today,
even when connected to modern controllers.
Kees.
--
Kees Stravers - Geldrop, The Netherlands - kees.stravers(a)iae.nl
http://www.iae.nl/users/pb0aia/ My home page (old computers,music,photography)
http://www.vaxarchive.org/ Info on old DEC VAX computers
(Mirrors: http://vaxarchive.khubla.com/ and http://vaxarchive.sevensages.org/)
Net-Tamer V 1.08.1 - Registered
From: Jim Battle <frustum(a)pacbell.net>
>clarifies the matter at hand. I claim that a floating point
representation
>specifies precision and has nothing to say about accuracy (other than
>accuracy is limited by precision).
Floating point binary is infamous for it's errors in that regard.
>To clarify, say a number is 175.136985. This represents my weight very
>precisely, but whether it is accurate or not is a different matter.
Ah but if you convert it to a 24bit floating point (more bits would help
but limiting it makes the error glaring) you may not be able to express
it
accurately enough. The BCD case induces more truncation limiting
precision.
>Again, I must be missing something, or perhaps it is a definitional
>thing. I've given my definition for precision (or what you call
>resolution) and accuracy. I claim accuracy is largely outside the scope
of
>a number representation. Perhaps you and others have a different
>definition than I do and are also internally consistent. I'd like to
hear
>it, since I keep running into it and don't understand it.
Accuracy express 1/3 binary and decimals for the same total bits.
Limit the case to something shorter than the usual 32 or 64 bits
say like 10 or 12 bits and you see the error. This is the gray zone
where
resolution, accuracy and range can collide. Of course with 128 bits of
either
case it's really meaningless then.
Back in the olden days (8080/z80/6502) when math was often limited in
the number of bits to something less than 32 bits this was more accutely
noticed by the users. The infamous MSbasic 3.99999=4 and other examples
come to mind. This led to things like NS* basic and HP using BCD to
avoid
the SQRT(16)=3.99999!
>If, on the other hand, you want to know what is sin(0.1), I claim the
>binary representation is more precise (and thus allows more accuracy;
>accuracy here depends on the implementation of the trig algorithms and
not
>inherently in the number system).
But the number of bits do make a difference.
>maybe I should give up and take this to the
alt.ieee.vs.bcd.floating-point
>newsgroup. :-)
Logically your correct but in the realm of older machines this was a real
issue.
Allison
From: Tony Duell <ard(a)p850ug1.demon.co.uk>
>AFAIK it is not backwards-compatible, at least in the sense that no
>10Mbps ethernet controller supports the 3Mbps data rate (at least, I've
>never seen one that does).
Neither have I. Also Eithernet AKA 802.x was never that slow. The
3 mb/s stuff I'd always called ARCNET.
>There were no single-chip ethernet controllers, if that's what you're
>asking. The ethernet circuitry for the classic PERQ (which was generally
>10Mbps, but early enough that single-chip controllers didn't really
>exist) is a 2910 sequencer, some microcode PROMs, some 9403 FIFOs, and a
>lot of TTL glue logic (and some comparator-type parts for the interface
>to the AUI connector). It takes up about 1/3rd of the EIO board.
Correct, there wasn't current LSI that was fast enough in the beginning.
The would change fairly quickly by 1984-85ish.
Allison
On Apr 24, 19:24, Tony Duell wrote:
> >
> > At 07:22 AM 4/24/01 -0700, Cameron wrote:
> > >> I just picked up a Commodore 8050M dual 5 1/4" disk drive with a
HP-IB
> > >> interface in a surplus place. Can anyone tell me what system(s) it's
made
> > >> to work with?
> > >
> > >PETs, of course!
> >
> > Any PET? I have an 8032 in DEEP storage.
>
> I use an 8050 on my 8032SK, and it works fine. The 8032SK is an 8032
> logic board in a plastic case with a separate keyboard. So as far as I
> know, the 8050 will work with the normal 8032 as well.
I can confirm that it does (well, mine does). Any PET with Revision 3 or
later ROMs does.
--
Pete Peter Turnbull
Network Manager
Dept. of Computer Science
University of York
Hi,
I have a few computers - C64, TI-99/4, that power-up
with garbled characters on the screen.
Otherwise, they seem to function correctly.
What does this indicate?
Bad RAM?
Bad ROM?
Thanks!
Steve
__________________________________________________
Do You Yahoo!?
Yahoo! Auctions - buy the things you want at great prices
http://auctions.yahoo.com/
Hi all
I am in the process of finishing my spring cleanup and I am giving a RS6000
7012 320H powerserver its very last chance to see if I can get it to do
anything usefull. I think I have mentionned this machine here before, still
I am looking for some help on this.
The machine is probably all ok. It was booting of the HDs with the original
AIX when I got it and still will boot with the diags floppy disks for RS6000
and I can "talk" to it from a terminal connected to the 1st serial
port....The HDs were taken out a bit later and the machine was left sitting
in a corner for a long time. Machine has 80 Megs RAM, SCSI card...the
hardware is acting ok. I dont have the keyboard, graphics card or monitor so
I am woking this thing from the terminal connected to the serial port.
I have AIX on 2 cd's they say ENTRY SERVERS R4.2.1. I checked on my Linux
box and the files are there and the cds are readable.
I have connected a Pionner DR-706S drive on the SCSI chain and also added
one of the original HDs (was flushed of original AIX and used somewhere
else) with a different ID on the chain. Chain is terminated at the end.
I am trying to get this thing to do something usefull by re-installing AIX.
I cant get it to boot AIX and install off the CDrom.
I tried the CDrom at ids 5 and 6 (suggested in some AIX newsgroup posts for
similar situations)
The CD is configured for 512 byte block size... its a Pionner. I know that
some CDROMs will not boot these RS6000 but is the only issue the block size?
I have heard that Plextors, Pionner and original IBMs will boot these
Rs6000. I have older toshibas and DEC that should support 512 blocks, should
l I try these or its hopeless?
I did put the machine in service mode...I did try to disconnect the battery
to reset the bootlist.
What is happenning now with HD and CDROM connected is machine goes through
post and displays 253 then looks like it goes into a never ending loop of
resetting the SCSI bus about every 2 or 3 minute or so.
I can see the leds on both the HD and the cdrom flicker (cdrom also spins up
and led flashes briefly every 2 -3 minutes or so) so I am suspecting that
the RS6000 is seeing something on the SCSI bus and the machine is looking
for something to boot with.
I suspect it sees the devices because without the HD connected, it will go
through post and then the floppy led will flash every few seconds waiting
for the boot/diag floppies. I suppose it does not see any SCSI devices so it
abandons booting from those and expects some floppies...
The Pionner CDROM alone on the SCSI chain will result in the machine
expecting floppies...so now I wonder if the CDROM is being seen at all...
Ideas anyone?
Thanks
Claude
http://computer_collector.tripod.com
Sorry, I deleted the original message on getting the rs/6000 to boot from
CD rom but intended to reply
The author mentioned a code 253, this is supposed to be "Attempting a
service mode IPL from SCSI attached devices specified in the ROM device
list"
The AIX manual lists the following steps to boot from installation media
seems like obvious stuff you've probably already done
1) turn on external devices
2) switch to service mode
3) installation media in cd drive
4) turn on rs6k
5) eventually you should get bos install menu
I could not find any mention of required scsi ID's for the CDROM.
Here is portions of the bootlist man page which might be helpful
Description
The bootlist command allows the user to alter the list of boot devices
scanned by read-only-storage (ROS) when the system is booted. This
command can alter the contents of the two battery backed-up RAM (NVRAM)
boot device lists and the choice of boot device used on the next and
subsequent system boots. This command supports the updating of the
following:
* Service boot list. The service list designates possible boot
devices when the front panel keylock is in the Service position.
* Normal boot list. The normal list is used when the keylock
is in the Normal position.
* Previous boot device entry. Retained in battery-backed-up
RAM on the system unit.
Each list contains a maximum of 84 bytes. When searching for a boot
device, the ROS system selects the first device in the list and determines
if it is bootable. If no boot file system is detected on the first
device, ROS moves on to the next device in the list. As a result,
the ordering of devices in the device list is extremely important.
If no device list has been supplied, or if it was empty, the ROS system
attempts to boot from the boot device used on a previous boot. (This
assumes that the previous boot device was not a diskette drive.) If
this boot device is unavailable or not bootable, the ROS system starts
searching the I/O bus for the first device from which it can boot.
The bootlist command supports the specification of generic device
types as well as specific devices for boot candidates. Possible device
names are listed either on the command line or in a file. Devices
in the boot device list occur in the same order as devices listed
the invocation of this command.
Device Choices
The device name specified on the command line (or in a file) can occur
in one of two different forms:
* It can indicate a specific device by its device logical name.
* It can indicate a generic or special device type by keyword.
The following generic device keywords are supported:
fd Any standard I/O-attached diskette drive
scdisk Any SCSI-attached disk (including serial-link disk drives)
badisk Any direct bus-attached disk (Model 320 only)
cd Any SCSI-attached CD-ROM
rmt Any SCSI-attached tape device
ent Any Ethernet adapter
tok Any Token-Ring adapter
fddi Any Fiber Distributed Data Interface adapter
<snip>
When a specific device is to be included in the device list, the device's
logical name (used with system management commands) must be specified.
This logical name is made up of a prefix and a suffix. The suffix
is generally a number and designates the specific device. The specified
device must be in the Available state. If it is not, the update to
the device list is rejected and this command fails. The following
devices and their associated logical names are supported (where the
bold type is the prefix and the xx variable is the device-specific
suffix):
fdxx Diskette-drive device logical names
hdiskxx Physical-volume device logical names
cdxx SCSI CD-ROM device logical names
rmtxx Magnetic-tape device logical names
entxx Ethernet-adapter logical names
tokxx Token-ring adapter logical names
fddixx Fiber Distributed Data Interface adapter logical names
<snip>
Attention: Care must be taken in specifying the possible boot devices.
A future reboot in Normal mode may fail if the devices specified in
the device list become unbootable. A diskette boot is always available
when the keylock is in the Service position. The system must not be
powered off or reset during the operation of the bootlist command.
If the system is reset, or power fails at a critical point in the
execution of this command, a checksum error can cause the system setup
information in battery-backed-up RAM to be lost.
The file specified by the file variable should contain device names
separated by white space:
hdisk0 hdisk1 cd1
or one device per line:
hdisk0
hdisk1
cd1
--
Hello all,
I have the following stuff available, free for local pickup in North Central
Massachusetts, USA, or for cost of shipping to the world (US Postal service
ONLY). Of course, if you want to offer real money, that's fine too :-), but
as you will see, there isn't too much here worth anything ... I'm moving at
the end of May, and don't feel like moving these things... There will be
more later...
- Commodore 64 CP/M 2.2 - Cart, manual, disk, original box
- Qty. 3 Apple IIc -- From an old school district, dirty, engraved,
yellowed. Boot DOS 3.3, no power supplies
- Commodore C-64C -- Yellowed, but functional -- bare computer
- Commodore 1530 Datasette unit model C2N -- untested, original box
- Commodore Modem 1200 -- Model 1670 -- no box or manual
- Thunderchopper game for C64/128 -- manual, disk, no box
- Apple Joystick for IIe/IIc, Model # A2M2012
- Apple TV Switch Box for Apple IIc
- TI Joysticks for TI-99, # PHP1100
- Qty. 2 Multi-cassette recorder cables for TI-99
- DEFCON 5 game for C-64/128 -- disk, manual,box
- IFR (Flight sim game) for C-64 -- disk, manual, no box
- Commodore Video Cable (6-pin DIN marked "Monitor" to 8-pin DIN marked
"Computer")
- IBM Data Collection Terminal 7527 (RS-232, 422/485 ports, three other
ports, possibly serial), no power supply (needs 26 VAC,.5A)
- TI-99 software (NO boxes, cart and manual only):
- Oldies But Goodies - Games I (cassette)
- Star Trek by SEGA
- Munch Man
- Number Magic
- Football
- TI Invaders
- Personal Real Estate
- Statistics
- Parsec
- Multiplication I
- Hangman
- Blackjack and Poker
Email me (OFF-LIST) your address and lists (first come, first served) and I
will quote shipping. You must prepay shipping (PayPal, money order [US $
only], or cash [US $]). If you wish to pick up locally, let me know, and we
can make arrangements (I'm about 1hr. west of Boston, or about 1 hr. north
of Worcester).
If you need an immediate reply, email me off-list, as I only get the
digest...
Rich B.
Does someone have binaries for tcsh and perl (just the executable, not the
libs) for sparc-sunos-4.1? Prefer 4.1.1. I can't get gcc running on this
Solbourne because it looks like AST stripped a whole bunch of include files.
(which means the included C compiler doesn't work right either, sigh). lynx
would also be wonderful if you have it :-)
Thanks!
--
----------------------------- personal page: http://www.armory.com/~spectre/ --
Cameron Kaiser, Point Loma Nazarene University * ckaiser(a)stockholm.ptloma.edu
-- Work harder! Millions on welfare depend on you! ----------------------------
On Apr 24, 10:41, Innfogra(a)aol.com wrote:
> In a message dated 4/24/2001 6:48:48 AM Pacific Daylight Time,
> rigdonj(a)intellistar.net writes:
>
> > I just picked up a Commodore 8050M dual 5 1/4" disk drive with a
HP-IB
> > interface in a surplus place. Can anyone tell me what system(s) it's
made
> > to work with?
> It should work on any Commodore with a GPIB port. This was usually traces
> brought out to the Circuit card edge for an edge connector to connect
with.
> Edge connector on one end and GPIB on the other end.
Not *quite* any PET. It won't work with early PET 2001 series that still
have original ROMs, because there are bugs in the IEEE-488 routines
(printers work, but not much else). That's why I want a two-ROM-set
piggyback board for mine.
--
Pete Peter Turnbull
Network Manager
Dept. of Computer Science
University of York
