So i got my newest toy, a HP Integral running. Problem turned out to be
cold solder joint at the Powerok signal. Strangely enough the current
carrying pins nearby were OK.
Thanks to Tony and Joe for the pointers...
A mechanical problem with the floppy will be sorted later.
First impressions : this thing badly needs a harddisk....
Second : if this is HPUX 5.0, what must HPUX 1.0 have been....
Of course i do no have software and manuals. Am i wrong to believe that
the system is only really usable with a harddisk, or am i overlooking
something ?
Jos
On Mon, 14 Mar 2005 woodelf <bfranchuk at jetnet.ab.ca> wrote:
> der Mouse wrote:
>
> >Well, it sounds reasonable, but probably isn't the most useful, as it
> >would mean that, for example, the PDP-8 had 12-bit bytes.
> >
> >
> >
> Umm words... it has six bit bytes. I think the lack of 18 bit byte
> cpu's has limited
> the use of 9 bit bytes. ( No comment from any 36 bitters )
What, the PDP-8? No, it don't have six bit bytes. The architecture don't
have any byte view (unless you count the BSW instruction in the 8/e and
newer, which might be argued as a byte instruction).
Software implemented bytes in various ways on the PDP-8. You have sixbit,
8 bit, and 12 bit bytes.
OS/8 for instance packs 3 8-bit bytes in two 12-bit words.
> >>The PDP-10 is an excellent example of when this isn't true.
> >>The smallest addressable unit is a word, which is 36 bits.
> >>A byte is, as noted, anything between 0 and 36 bits. Bytes are
> >>stored in a word, as many as can be fitted. To access bytes on a
> >>PDP-10, you have a byte pointer, which consist of a word address, and
> >>a bit pointer, and byte size.
> >>
> >>
> >
> >That sounds a whole lot like a hardware-supported way of addressing an
> >object of an arbitrary size in bits. And that would mean that bytes of
> >any size *are* individually addressible.
> >Or have I misunderstood?
> >
> I belive so, but I have not programmed a 10. I suspect this is in
> regards to string operations
> rather say accessing character sized data data. Two different things.
No difference between a string, or character sized data. Character sized
data layed out in sequence becomes a string. The instruction that deals
with bytes only handles one byte at a time. Chug through several
characters and you have processed a string.
> >>The fact that people today seem to believe that byte addressable is
> >>the only possible thing, along with a byte being 8 bits, is plain and
> >>simply because they haven't seen any other.
> >>
> >>
> Well in most cases a byte is a unsigned 1/2 half word. I still like view
> of the PDP-11 a byte
> is signed data. I think the lack of real byte access has forced the C
> standard to have unsigned
> bytes because the machines ( 8080,Z80) can't handle real bytes .
Huh? What are you talking about???
All these machines (as well as most anything past 1960) uses 2-complement,
so there is no need to differentiate between signed and unsigned, it's
just a matter of interpretation. The one time it makes a difference is
when checking results, and the PDP-11 have both signed and unsigned branch
conditions, so it don't view a byte as either one or the other. It's up to
the programmer to choose. The same with a Z80. I would assume that the
8080 also have the same status flags, and thus you can pick wether you
want to play signed or unsigned at will.
And a byte on a PDP-11 is not 1/2 half word, but just a half word. A word
is 16 bits. That's why, on a VAX, a 32-bit thing is called a longword. But
for some reason some other manufacturers decided to call 32 bits a word,
so 16 bits became a "half word", but let's keep that away from the PDP-11,
please. No revisionst stuff here. :-)
Johnny
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: bqt at update.uu.se || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
I'm also still looking for a VT-50 for
my Wofford Witch computer center to add
the authenticity factor to it. The VT52
terminals that I have are filling in quite
nicely, and yes, they are a better terminal
than the VT50, but I would like to find a
working VT50 just to make a system a more
authentic replica of the original 1978
computer center.
Ashley
Anyone out there have a working VT-100 terminal
and keyboard they'd be interested in selling? I
need to get one to replace one that I'm giving away
with a system.
If anyone has one for sale, send me a private
reply to wacarder at usit.net.
Thanks,
Ashley
Was someone looking for ProComm Plus awhile back? I found a copy on 3.5 FD
today in the warehouse along with several manuals of different versions.
Let me know what you need from it. John
At the risk of tilting your age spectrum report, I must admit to possibly being the eldest computer nut on the list. I noticed a complete lack of cohorts in this age group, they must be either all deceased or devastated by Alzheimer's....
Fred Hatfield, age 76.
Richard wrote:
> 4) All RW media (DVD-RW DVD+RW CD-RW) have poor archival life.
> Think about it: with RW, instead of burning a pit in the data
> layer, you are fooling around with glossy or matte finish
> depending on how quickly a melted liquid re-freezes. Official
> tests, and my own tests, show poor life. A little sunlight-UV
> can erase it.
Eric wrote:
>It was my understanding (perhaps wrong?) that RW media uses a phase
>change to store the data, and that it takes significantly more energy
>to induce the phase change than to induce a chemical change in dye
>for write-once media. That's why it can't be written as quickly.
>If it really works that way, one would reasonably expect RW media to
>have *better* longevity than write-once media.
>So is my premise wrong? Does rewritable media not use a phase change?
>Or is the activation energy comparable or lower than that for write-once
>media?
I don't know about activation energy. Sorry. But the resultant RW
disk is less reliable, and has shorter archival life.
Richard:
> My least favorite factory is CMC Magnetics
Eric:
>They seem to make about the worst CD media, so it's unsurprising
>that they make poor DVD media.
Richard:
> I think Pioneer and Verbatim buy their media from
> the good Japanese companies, Mitsubishi, Taiyo Yuden, and Mitsumi.
Eric:
>By "Mistumi" you must have meant "Mitsui"? For CD media, Taiyo Yuden
>and Mitsui are definitely the best.
Richard:
Yes, I meant Mitsui. It was a typo. Mitsumi is I think a maker
of floppy disk drives in Japan, and not media. Mitsui and Taiyo Yuden
make good media, and sell organic dyes and other chemicals to many
of the lesser media making companies.
Richard:
> TDK seems to be only advertised brand that makes their own
Eric:
>I used to buy TDK CD-R media at Costco because it was made by
>Taiyo-Yuden. Then they switched to CMC Magnetics, and after
>using one spindle of that (with >50% reject rate), I refuse to
>ever buy media from them again.
>I'm surprised that TDK would make their own DVD media when they don't
>make their own CD-R media. More likely they're contracting out
>manufacture and getting the vendor to mark the metadata as TDK.
>Eric
Richard:
I'm sorry to hear that. I know their media code says TDK,
but you are correct, maybe they didn't make it. But it tested
well.
========== ADDITION TO RICHARD's PREVIOUS POST =====
In my original message, I forgot to add: ...
7) If you really care about it's archival life, hedge your bets
by burning two copies, on DIFFERENT media. Select two good
media types made by different companies. Each may have, just
a guess, a 10% chance of self-destructing within 20 years.
This would be because of a design or implimentation mistake.
For example perhaps the sandwich adheasive includes a chemical
that eventually reacts badly with the data, or some impurity
in manufacturing at that time. If the two media are very
different, their probabilty of failure approaches statistical
indpendence; and if independent then the chance that both are
unreadable would approach 0.1 * 0.1 or only a 1% chance.
Richard Bristol bristol22 [at] softhome [dot] net
> Just like stating raw clock speedtoday for marketing.
>I can buy a N GHZ machine but can anybody tell me
> the real speed of instruction abc on data xyz?
Sure, if you know all of the environmental issues (condition of pipeline, status of cache, etc).
I have worked on a significant number of Pentium (and other pipelined
multi-level cached) based systems for engineering projects, and
*sometimes* we do have to actually still calculate this stuff out to
prove that a design will work under various system and data conditions.
I remain convinced that USB, not parallel, is the "right" way to go for
interfacing a Universal Floppy Disk controller.
The whole purpose of the device is to be a "bridge" between old and new.
The "old" side is fixed, it's the drives we want to interface to.
But the new side is "today's PCs", only "today" really doesn't mean "today"
but really today and tomorrow.
Parallel and serial ports are disappearing RIGHT NOW. Some new PCs -- most
new notebooks -- already don't have them (and yes, I might want to use this
with a notebook). It's 2005 now, and we are talking about designing a
device that doesn't exist yet. What about 2008, 2009 ..... even 2015? USB
interfaces essentially "started" in about 2003 and in my view will likely
exist for about as long as RS-232 devices existed, e.g. decades.
Why?
What was RS-232 used in? Electronic equipment, LOTS of it, but almost NO
consumer equipment.
What is USB used in? Electronic equipment, lots of it. AND ... Digital
Cameras, MP3 players, cell phones, GPS receivers .... the list is endless.
USB is both just starting, and so completely ubiquitous (and, very
importantly, in BOTH "lab" equipment AND "consumer" equipment) that it's
going to be around for decades to come. Parallel port? The primary use has
always been printers. But you can't even find a printer with a parallel
port easily, and parallel ports in PCs are already starting to disappear.
This is a device that we want to be useful now and in the future, and I
firmly believe that any serious analysis will conclude that USB is the way
to go.
[Someone questioned if the speed was adequate. USB 1.x is 12 megabits per
second, USB 2.x is 480 megabits per second. The target devices are floppy
disk drives, to which the maximum write bitrate is 1 megabit per second.
Clearly USB 2 can do absolutely anything that would be relevent, and there's
not much, if anything, that USB 1 couldn't do.]
