test-drb April 2001

test-drb@ccmp.vtda.org

251 participants
669 discussions

by kees.stravers＠iae.nl

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

23 years, 8 months

BCD accuracy (was: HP 85/Rocky Mountain BASIC replacement)

by ajp166＠bellatlantic.net

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

23 years, 8 months

3Mb Ethernet

by ajp166＠bellatlantic.net

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

23 years, 8 months

Commodore 8050M disk drive. What's it for?

by pete＠dunnington.u-net.com

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

23 years, 8 months

Partially garbled screen means what?

by tosteve＠yahoo.com

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/

23 years, 8 months

Booting an older RS6000 off cdrom

by claudew＠videotron.ca

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

23 years, 8 months

rs6000 cd scsi boot problem

by thompson＠mail.athenet.net

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 --

23 years, 8 months

Free (or price of shipping) Stuff -- Part 1

by r_beaudry＠hotmail.com

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.

23 years, 8 months

SunOS 4.1.x binaries

by spectre＠stockholm.ptloma.edu

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! ----------------------------

23 years, 8 months

Commodore 8050M disk drive. What's it for?

by pete＠dunnington.u-net.com

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

23 years, 8 months

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test-drb April 2001