test-drb December 2003

test-drb@ccmp.vtda.org

252 participants
453 discussions

HP2000 Tape Conversion

by pete＠dunnington.u-net.com

On Dec 9, 20:28, Ron Hudson wrote: > > Somewhere, once upon a time, I found on the net an HPBasic interpreter > either > for windows or for DOS... I don't know where it was though. > > Shareware / Freeware I think. Might have been TransEra's HTBasic -- but it's commercial. http://www.techsoft.de/htbasic/htbasic.htm One of several good places to look for informaton about BASIC in various forms is http://www.icewalkers.com/opd/Computers/Programming/Languages/BASIC/ -- Pete Peter Turnbull Network Manager University of York

21 years

HP-85 Rom Emulator

by bkotaska＠charter.net

I'm working on a ROM emulator for the HP-85 - i.e. a replica of the original (and hard to find) Programmable ROM Module. From photos (thanks to Vassilis Prevelakis), I've drawn a schematic of most of the original module. But I've hit a snag where some of the traces disappear under the ICs. I've been able to deduce most of these but some are too ambiguous to "pin" down. Is there someone who owns this elusive module that would be willing to ring some paths for me (probably 10 to 20) ? Some connections may be obvious simply with a closer visual inspection of the actual module. Thanks, Bill

21 years

USB 5.25 floppy

by cb＠mythtech.net

>Using *ANY* floppy on a PowerMac is painfully slow. When I was getting >ready to move from my 8500/180 to my G4/450 AGP I wanted to image a large >number of floppies that I had. I ended up doing the imaging on my >PowerBook 540c, transfering them via ethernet to the 8500 and burning them >to CD. That was a *LOT* faster than doing the reading directly on the 8500. I've seen no speed issues with floppy disks on any of my PowerMacs. Nor is there a speed problem with my brother-in-law's iMac and a USB floppy drive (Imation?). I've tested my slow USB drive on other iMacs, and its always slow... and I've used my brother-in-law's drive on the same iMacs with no speed problems... so I'm pretty convinced the speed problem is with the drive. -chris <http://www.mythtech.net>

21 years

HP2000 and old archive stuff NOT on 9-track (apple2 transfer??)??

by pete＠dunnington.u-net.com

Kermit, probably, unless you already have a terminal program with file transfer capability on the Apple. You can get versions for just about anything, at http://kermit.columbia.edu/kermit/howtoget.html or mirror sites. Kermit can transfer binary files without loss or corruption between all sorts of systems. The tricky part is getting file transfer software onto the Apple in the first place. Kermit-65 (for the Apple ][) is available as a hex file which you can transfer fairly easily and convert to a working program; after that, the rest is easy. Look for the files that start "app..." for Kermit-65 for the Apple. ftp://kermit.columbia.edu/kermit/a/appaaa.hlp will tell you what they all are, and get you started. It's easier for the PC, all you need to do is download the relevant program (I'd suggest the slightly older DOS version, which is free, and works under Windows as well, despite the disclaimer -- or at least, it does for me). -- Pete Peter Turnbull Network Manager University of York

21 years

Reel-to-Reel care

by aek＠spies.com

> in the absence of manuals I had to dismantle it to find out how I *should have* dismantled it www.bitsavers.org/pdf/hp/tape/07970-90887_7970svc_Dec77.pdf This was for the B series, but the mechanics are the same as the A. > Is the oxide coating stable Depends on the formulation. Early 80's formulas (esp. Memorex) will (has..) become unusable. I've personally had much less problems with 3M formulations. The long term prospects of tape transports with any rubber parts is not good, either. Almost all of the 1/4" cartridge tape drives I own are inoperable because the drive pinch rollers have turned to goo.

21 years

Reel-to-Reel care?

by aek＠spies.com

> I've got old BASF and Memorex tapes (20 years +) that are fine You are extremely lucky. Memorex early 80's tape is the worst stuff I've ever had to deal with, esp MRXIV (red label) andn MRX?? (light gray) If you have anything you care about, get it off of those reels ASAP. It is classic "sticky shed syndrome". The binder becomes sticky and glues the layers of tape together. If you're interested in the details, you might want to try to find a copy of "Tribology and Mechanics of Magnetic Storage Devices" by Bhushan esp the chapter "Role of Chemical Properties in Magnetic Tapes". --- Magnetic tape media has become the bane of my existance :-< The sooner that I can get rid of every mag tape I own, the better...

21 years

Disk hardware emulation, was Re: Grandfather system RTE6/VM?

by dwight.elvey＠amd.com

>From: "John Lawson" <jpl15(a)panix.com> > > >On Tue, 9 Dec 2003, Eric Smith wrote: > >> The part of the ST-506 disk emulation that's of most concern to me is >> whether anything needs to be done about write precompensation. The >> controller shifts the pulses on write to compensate for the peak >> shifts that happen on magnetic media when flux changes are recorded >> close together. > > > > Is it not true that the precomp circuits are driven by head position >info - thus the 'solid' version (emulation) of any drive would just be >permanently 'stuck' in one mode or the other would the controller care, or >even know, what track and cylinder the actual 'data' were coming from? Hi Some controllers used the cylinder information to turn on the compensation for the inner tracks. > > I don't know if this would cause the emulator qua emulator to fail at >some perhaps subjective level - but I can't see where one would need to >actually legislate write precomp into a block of RAM. > One can see from the timing that there is compensation being written. My understanding is that the selected compensation is only used for the write. The read amps do have some non-linear response to compensate for the normal effects of megnetic data. From what I've seen, the read is fixed for and compensation so regardless of the track, one should be able to provide data with the same framing as any other track. Dwight

21 years

Disk hardware emulation, was Re: Grandfather system RTE6/VM?

by dwight.elvey＠amd.com

>From: "James Dickens" <jdickens(a)ameritech.net> ---snip--- > >okay not an expert, but most systems using these drives used interleaving of >sectors(because there was no way the system was fast enough to handle the >data), the IBM PC used a factor of 6. The machine the device would not know >what to do with 30MB/s of data if you produce it. i doubt any machine having >such a drive would benefit from more than 4MB/s and producing data faster >than the machine expects can cause timing errors, that were not noticed when >the machine was new. i guess after the device is made.. yo u will have to >spend more time slowing it down than trying to get it faster. > ---snip--- Hi As far as I know, all PC hard disk interfaces had at least a one sector buffer. This is unlike the floppy interface that did byte for byte DMA. Dwight

21 years

Reel-to-Reel care?

by ken＠fraserhouse.com

Greetings, Does anyone have some "care and feeding" tips for vintage reel-to-reel tape drives? I've recently purchased a couple nice 9 Track drives, and want to make sure they (and the media) last as long as possible. I've already given the heads, rollers and guides a good cleaning with 99.9% anhydrous Isopropyl Alcohol using 'fuzzless' cotton cleaning sticks, and plan to do so on a regular basis. Is there such a thing as too much cleaning? ;) What other tips and tricks should I know? For example, should I always unload and store the tapes in their carriers immediately after I'm done using the drives, or can I safely leave them loaded for an extended period (oxidization? de/magnetization? deterioration?). They definitively look cooler with tapes loaded :) Thanks, Ken C.

21 years

Virus Distribution via this group

by pete＠dunnington.u-net.com

On Dec 9, 11:22, Frank McConnell wrote: > Paul Williams <paul(a)frixxon.co.uk> wrote: > > Pete Turnbull wrote: > > > > [Quoting headers from one of Tony's emails] > > > >> Content-Type: text > >> Moreover, they have no attachments, no hooks for attachments, and > >> nothing other than correct ASCII headers and plain ASCII text (as, > >> indeed, the headers indicate). > > > > This header is invalid according to RFC 2045, because it should > > contain a type and subtype (in this case, it should be text/plain). > > Please read section 4 of RFC 2045, then try to find the > "MIME-Version:" header in Tony's messages, then you may understand > that Tony's mailer isn't sending MIME messages. There is some > language in that section that permits software to interpret non-MIME > messages "according to local conventions", but if it tries to treat > non-MIME messages according to the MIME standards and loses, then I'm > free to consider it broken, and I do! So do I -- "be generous in what you accept and strict in what you create" or similar words. On the other hand, RFC1049 doesn't allow the "Content-type:" that Tony's mail contains, nor does RFC822, and as you imply, Tony's mail isn't MIME-compliant -- so it's broken too. -- Pete Peter Turnbull Network Manager University of York

21 years

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test-drb December 2003