1696 posts • joined 15 Jun 2007
Re: Oh FFS @AC 15:12
I would suspect that you have an X Windows client program that is warping the cursor back into it's window every time that that it detects that it is going outside. As for the buttons, it could either be changing the button mappings, or re-parenting the root window to trap the button events. These would not be problems with the X11 server, more like a poorly written client using the server incorrectly.
I actually wonder whether you are running an older ATI radeon card (something like a Thinkpad T30 or T43). If that is the case, it could actually be that you are suffering from a problem with the display driver not being reset correctly after suspend/resume. If that is the case, then disabling KMS may be the solution (google nomodeset or modeset=0). It's a pain, I admit, but the upstream developers regard R100/RV200 and R200 as being obsolete nowadays, so are not interested in fixing the problems. The adoption of Unity and now MIR (especially if they completely ditch X11 compatibility) will be close on a deal-breaker for me and Ubuntu. The shiny is just not worth losing X11 for. At leat Wayland has an X11 compatibility component.
I've got 12.04 running on my T30, and get strange things happening, but I am working with the pm-suspend tweaks to make the problem less intrusive.
Re: Outages @Fletchulence
Sure, outages happen. But good design should make such an outage relatively short. Keeping critical systems up even when things are failing should be part of the design and change process.
One day's down time for a regional health authority equates to hundreds of thousands of pounds of wasted resource, even more if you take into account the time of the people who attended their out-patients appointments without being seen.
I sometimes remember when I used to talk to a power engineer in a regional electricity distribution company, where five nines is a way of life, not an aspiration.
Ah, but if the problem is in-house, with your own employees, then you can at least bang some heads together and threaten to kick people out of the door.
If the problem is either in the Cloud, or with some outsourcing outfit, all you can do is threaten to not renew your contract in 4 years, by which time everybody will have forgotten!
Of course, if the contract was negotiated properly, you may get some financial recompense, but I don't trust any of out public organisations to be that good at getting such clauses into a contract....
Re: Phones are on the verge of desktop replacement
"Does the EU think that will work over micro USB?"
Why not? My Sony Xperia SP has a single micro USB port that provides MHL output to drive a display over HDMI, the capability to charge, and also to drive a USB Keyboard and/or mouse. All at the same time.
AIX since 1986
Well. I doubt very strongly that there are any 6150/1 systems running in anger any more, or any PS/2's running AIX PS/2 or mainframes running AIX/ESA, so they really only need to worry about POWER boxes, and they started in 1990. That takes out anything before AIX 3.1.
And since then, the Microchannel architecture AIX boxes can't run a supported version of AIX, nor can any 32 bit POWER systems or any with RS64 processors, so they really only have to worry about 64 bit CHRP systems that run AIX6.1 and later. That means that they only have to worry about systems built since about 2000! And as the basic OS running under 6.1 and 7.1 is not really different under the covers, and basically is compile once/run anywhere, it's a much smaller target than Solaris or HP/UX.
So a bit of diversion going on here to detract from the fact that they really must be a bit thick!
Re: Hmmmmm..... @Matt
I would have thought that a SteamBox running in streaming mode from your gaming rig would be exactly what you needed to play games in your living room. Best of all worlds.
Re: Ignore the obvious choice @Steve the Cynic
I believe that the IBM Enhanced Keyboard was available for the PC/AT as an option from launch in 1984, before the PS/2. Wikipedia states that the manufacture of the Model M keyboard started in 1984.
I'm fairly certain that the first PC/ATs (early 6MHz models) bought by the Polytechnic I worked at in the 80's all came with UK model 102 key keyboards.
Re: What a waste of time and money@ Don Jefe
There is a trend in the UK for people to install under-floor heating now (either electric or powered by solar/ground heat carried by water), but the huge majority of UK properties use water filled radiators warmed by boilers running on natural gas, oil or solid fuel (wood or coal). Gas is commonly available as a mains service in the majority of the UK, and is cheaper per thermal unit than electricity.
I think that hot-air heating is not used is mainly to do with the fact that it really requires the house to be built around the heating system as it requires substantial air-ducts to carry the air around the house.
I did live in a house built in the '60s that used hot air as the principal heating, and I have to say there are significant drawbacks in my view. The heating was noisy at the best of times, and deafening when the fan motor bearings wore out (it was a Canadian system running on 120V, not the 230V the UK uses, and made procuring parts very difficult). Also, the kids used the air ducts as an intercom, shouting through them. You always had to be careful about noise in the bedroom, if you know what I mean, because of the way the ducts carried sound.
But the primary problem was that it didn't really heat the fabric of the house or the hot water. If you didn't have and entry lobby acting as an air-lock, it was quite normal for all of the heat to rush out whenever anyone came in or out of the house. And when you get a bird in the ducts, it's a real problem trying to get it out.
Anyway, it never really caught on in new build houses, and water filled radiators were easier to retro-fit into older houses, especially with micro-bore pipes.
Re: What a tw@
Problem is that if his bag was already loaded, it might have delayed the 'plane still further in order to find and unload it.
Re: And the first step towards Skynet has been taken...
Ghost X-9 anybody?
Who said anything about IP? It's not the only network layer protocol around, although I admit it is the most common.
They may have a non-IP network that gets locally picked up via some innocuous device (hacked mobile phone maybe) and gated onto an IP network, or they might just have invented a non-IP peer-to-peer supernet mesh completely separate from The Internet.
Use some imagination, please!
Re: GCHQ Turing Test to Pass for UniVirtual Machine Command to Control Global Operating Devices*
Relax. It's AManfronMars 1. He/She/It is a Register regular, and very few of their comments make huge amounts of sense (although they just might!). Click on their name in the comment, and have a read.
Just don't try to understand it too much!
I really expect more from commentards who have been around here for a while!
I think the most common theory around here is that it is written in English, then translated into at least one, and possibly more than one other languages before being translated back into English.
As far as I am aware, all change control systems work like this, and have done for decades. I used SCCS on Bell Labs. UNIX 25 years ago, and it was the case then, and Wikipedia states that SCCS dates from 1972.
Re: Cheap? Just underwhelming @Lusty
"If you want a better phone for actually doing phoney things..."
...then my advise is to get a £25 Nokia or Samsung dumb phone. Tried and trusted technology, long standby and talk time, robust as hell, easy to use (as a phone), and it won't get you mugged or be particularly painful when you drop it down the loo or lose it when out on a bender.
Of course, if you want to run Angry Birds, then you really want more than a phone!
Re: Not saying anything but...
And passwords on privileged accounts every 30 days or less.
Not sure that many companies I've worked for actually abide by their own rules, however. For most companies, it looked like this was in the policies merely to satisfy an audit requirement.
Imagine having to change all the passwords on all your routers, intelligent switches, management consoles, data appliances - well anything that has a password that protects a configuration basically! I'm sure that most companies don't really know the scope of the problem.
Re: How strange to see that name again
Micrografx Picture Publisher used to be my go-to software for image manipulation on Windows (back when getting scanners working on Linux through the parallel port pre-USB was a real pain). They used to allow personal use of their old versions of software, and it often came as part of the software bundle that came with a scanner as well.
Although I don't have a lot of Windows boxes around now, those that are in my control generally have MPP installed on them still.
Well, they make white cider by passing diluted grain alcohol over the remains of the apple pulp after it's been squeezed dry of real juice. Probably imparts as much flavour as using the wood.
What the hell is going on here with the "Add an icon" tab? What was wrong with having the icons below the post! Has somebody at ElReg been drinking the Metro/Unity cool-aid?
Re: I remember watches @Omgwtfbbqtime
Me? I don't take my watch off, even in the bath.
Only time it comes off is to replace the battery, and so as not to scratch the wife when, um...
Oh, you know what I mean.
Not sure which of those two events happens more frequently nowadays!
Re: no wonder racing pigeons are sold for lots of money
"esethay arentay otntay hetnay igeonpays ouyay reajay ookinglay orfay"
"these are not the pigeons you are looking for"
Should you not have used/invented Pigeon Latin rather than Pig Latin?
Re: Switching from big iron to x86 virtualisation
Indeed, the sentence that reads "people are not willing to spend big money on mainframes – the Unix big guns" indicates that Dennis Yip has only a limited grasp of what he is talking about.
From a cursory examination, I would suggest that in his world there is just Wintel, and a single category of "everything else".
Second Impact was supposed to be in Antarctica!
Re: Security issue? @AC 09:01
"Sounds like is more a matter of having to page different regions then and iterate over them. Shades of paged memory again"
Except that the remote machine cannot manipulate the mapping registers that are used to control the window. If you can't manipulate these, then you cannot see memory outside of the region. And even the process on the local machine, which is running in non-privileged mode, cannot alter the mapping registers. This is a function of the OS, and is controlled by system call, with appropriate security.
I must admit that if you think that paged memory is a bad thing, then you must realise that you are condemning all current machine implementations that use virtual address spaces. All virtual address space machines use memory mapped pages to implement a linear virtual address within a physical address space, and also allow memory overcommitting (==using a page space on disk).
There are NO architectures currently that I know about that allow multiple processes in a strictly linear global address space that is the same as the OS. I don't know whether you work with some that I don't know about, or if you don't realise how modern systems work.
Re: Security issue? @oldcoder
I think it is safe to assume that for any architecture that implements RDMA, an IO MMU is essential. Anybody designing an architecture/system without one in this day and age would have to be regarded as terminally naive.
Re: Security issue? @AC 09:04
I'm as into Microsoft bashing where it is deserved as much as anybody else, but in this case, just because it is Microsoft that does not mean there is a problem. You could say that pretty much every OS has buffer overflow exploits (it is one of the problems of writing in C after all, and that is a language that has been used extensively for OSs) thus it's not only Microsoft's problem.
In terms of the OS setting the window, It is really set up so that the hardware MMU does the guarding, not the OS. The OS sets up the window, and then the MMU enforces it. The OS may set it up wrongly, but assuming that it is correct and the MMU is bug free, it becomes impossible for the remote machine to move outside of the constraints of the window. This is not an OS issue.
If you distrust the MMU, then you must distrust all architectures that use virtual address spaces for processes as well, as they all use the capabilities of a HW MMU to enforce the issue. It's been that way for multi-tasking OS's with virtual address spaces for decades, and wintel since NT is no exception.
Obviously some people hiding behind the AC banner have forgotten their system architecture courses, or are just trolling because they don't understand in the first place.
Re: Security issue?
RDMA is secure. It does not give access to the whole of the address space of a system (or at least the implementations I have used don't).
What happens is that the OS on the controlling side of the RDMA transaction sets up a limited window to a region of memory that the remote machine can see. The remote machine has no access to memory outside of this window.
This makes the access as secure as the OS on the controlling machine which set up the window.
In the implementations I have seen, there is an architectural limit on the size of the memory region in the window. This means that it is simply not possible to expose the entire address space of a machine using RDMA.
Re: Even more confused @Flocke Kroes
Windows users are now expecting to cut (or copy) and paste large objects.
I recently used a product on Windows (I can't remember what it was) where drag and drop copy between folders did not work. What they expected you to do was select a group of files, right-click-copy (or ^C), move pointer, click, and then either right-click-paste or ^V.
In this way, you could be copying multi-megabyte files. This will not work with a traditional X-Windows style cut buffer. I think this is what they are talking about when they are talking about cut-and-paste between VMs.
Even though I deal with HPC machines every day which do RDMA with the fastest interconnect in the market at the moment (at least I believe it is), I cannot understand how you can have remote access to another system's memory via RDMA faster than access to local memory. What this would imply is that the RDMA device (probably attached via PCIe) had access to the memory on a system faster than the processor. As the memory controllers of all current high performance machines are integrated on the processor die, I cannot see how it is possible for PCIe adapters to have faster access. If he is talking about VMs on the same machine, and using RDMA to access memory physically in the same system but in a different VM, the best he can do is have it running the same speed as 'local' NUMA memory.
I know they are talking about NUMA machines here, and that a processor may have to go across the internal system bus to talk to memory controllers attached to a processor on another die, but that across the bus access is not likely to be any less than the RDMA device that is in a similar position on the bus. Not unless the internal bus architecture of the system is seriously screwed up.
The only thing that I can imagine that he is talking about is having the memory 'mapped' and available via RDMA between two VMs on the same system faster than it could be copied across the interconnect from a remote (i.e. separate hardware system). That seems eminently possible, but that should not be a surprise.
It would be interesting to see whether the systems he has seen in the lab are the ones using PCIe4 as an interconnect.
Re: Hershey's chocolate
I saw in interesting documentary on Hershey that claimed the reason why American chocolate is so nasty is historical.
In the 19th century, Europe had a Chocolate fad. East coast America picked this up as Europe was trendy to Americans who lacked a long history, and looked across the Atlantic for trends and fashions. East Coast America is fairly cool and the major cities were fairly close together, so chocolate could be made and moved quite easily,
When the frontiers started getting civilised (mainly with the railroads), high quality goods from the east coast were sent around the country because those people wanted to be seen a sophisticated, and chocolate was a small luxury that could be afforded in small quantities. Unfortunately, America is a big place, and often quite hot.
This meant that chocolate arriving on the West coast or the South was often in box cars for days in hot conditions, and quite naturally went off. The milk in the chocolate became rancid. The people receiving such luxury items did not know that it was off because they did not have anything to compare it to, only knowing that it was the trendy thing to eat and just accepted that this was how it should taste, and got used to it.
When Hershey, Pa (aka Chocolatetown, USA) was built, and they commissioned refrigerated box cars on the railways to distribute the product in ideal conditions, the outcry about the change of taste from the rest of the US was so great that Hershey changed the process to re-create the taste of gone-off chocolate that Americans now favoured. And the rest is history.
Mind you, I understand that Americans now go wild about the taste of Cadbury's chocolate (and buying the company, unfortunately), so maybe they are beginning to see sense. Having said that, I guess that people from places like Belgium and France probably throw their hands up in the air at British chocolate, which substitutes vegetable fat for milk fat.
But I prefer it that way, and that's what matters to me.
Re: "Sci-Fi"? Tsk, tsk...
It's Scientifiction, I insist.
@Justin re:"don't understand..."
As a student, I bought a JVC KD-720 deck to go with my budget Hi-Fi. Now, 35 years later, it is the last original component of my system, and still works pretty well.
It was at the time the "Best Buy" budget (~£100) cassette desk, and (IMHO) did a thoroughly good job of recording and replaying music. The main problem was that it did not have a 'proper' FeCr setting, and pre-dated metal tapes, so could not use them (the Cr02) setting was also not really calibrated for psudo-chrome tapes like the TDK SA). It also only had a 'normal' tape head (not a Sen-Alloy one), so I was always expecting the head to wear, but even now, it's not too bad (apparently, early generation chrome and metal tapes were very abrasive, I guess that missing these tapes out prolonged the life of my deck).
Even this budget deck had a wow and flutter of 0.2% DIN, and a frequency response of 40-14000Hz with ferric tapes, and 40-15000Hz on chrome dioxide tapes.
I nearly always used TDK AD-90 ferric tapes to record, because they were the sweat-spot of the TDK range, providing good frequency balance (although slightly bright), good frequency extension (the brightness extended the upper ranges while minimising tape hiss) at an affordable price. They also used to be about 47 minutes long (useful for both sides of a long album) and very well made with friction reducing embossed teflon sheets either side of the spools. The Audio Society used to buy them by the case-full, and sell them at near cost to the members. TDK SA tapes were better but much more expensive, although I believe that the calibrated tape brand for JVC decks was supposed to be Maxell.
Anyway, my deck always gave exemplary performance. You could tell it was a tape from the hiss if you listened hard, but otherwise it sounded very good and I had very few tape jams or mangled tape in this deck. The sound of it persuaded several of my friends who had the "cassette tape is no good" attitude to change their mind and invest in a decent deck. It also helped having a reasonable music source to record from (turntable in the day).
To prevent jams, always wind the tape from end-to-end in a single operation and leave them on the leader before storing them. This prevents 'ridges' which increase the drag, especially on the take-up spool. If the take-up spool cannot be turned by the motor (remember it has a slip clutch so that it can cope with the varying diameter of the spool as the tape is wound on), then the capstan and roller will continue to feed tape in until it loops back on itself, and gets mangled. This was a common problem on C120 cassettes, because the nearly full spool was very heavy.
If it does look like this is happening, immediately re-wind the tape as best as you can before attempting to eject the tape. If you just eject the tape, you are absolutely guaranteed to break or stretch it, and will end up fishing out short lengths of broken tape forever.
I still keep iso-propyl alcohol around as a general cleaning fluid after using it for so long to clean the tape heads with cotton buds.
I used to read New Scientist when I was doing my O and A levels at school in the 1970s (it was an accepted use of free study time in the Library), and beside ogling the calculator adverts, I found it a good counterpoint to the taught science. It was sufficiently detailed to engage the mind of a scientifically curious teenager, with sufficient detail to be seen as useful knowledge, and would in my opinion be graded in content and detail above Horizon (which I used to watch regularly as well), and other science and philosophical programs such as The Body in Question and The Ascent of Man.
I continued to read it on-and-off through University (it was one of the popular collage periodicals in the Junior Common Room at my college).
Once I left University, I stopped reading it.
Recently I noticed that supermarkets have started putting it on their magazine racks, so I thought I would pick up an issue or two, with the intention of getting my late teen kids interested.
I was shocked! I thought that as I had not studied Science in the last 30 years, that i would struggle a bit with some of the developments and maybe some of the maths, but no.
The content was trivial, and the author(s) clearly felt that they had to explain everything from first principals. I found almost nothing taxing, and was able to get almost all of the articles by skim-reading them, missing out 70% or so of the content that I already knew. This was not the mind-expanding New Scientist that I had read thirty years ago.
I gave them to my 17 year old son, and he found nothing in them that he felt interested him enough to justify me regularly buying it (although he is a knowledge sponge, and read a lot on-line).
It's a terrible shame that one of the most approachable science publications appears to have done what I can only describe as dumbed down. But maybe that is just because the are following their audience, rather than leading it.
"Rent a Paris for my holiday!"
Not sure about the real one, but I'm sure you could find a lookie likie who would do most things you want for cash without needing any special technology.
Probably not a legal transaction in many places you would want to go to for a holiday, though.
I will support the views about inappropriate clothing, but mainly on the practical side.
If I had my way, I would ban anything approaching high heals in a machine room. This would include built-up boots, such as cowboy boots. The reason? Well suspended floors are never completely even, and if you put a heel over the edge of a raised or removed tile, accidents will follow (I believe you are more likely to maintain your balance with 'normal' shoes). Similarly, I would not want sandals or strappy shoes worn anywhere heavy equipment is being moved.
I also wonder how someone in a skirt would react to crawling under or around restricted spaces while trying to maintain their dignity, and if they did not care about their dignity, how much of a distraction that would be to their colleagues.
The comparison with suits that ShelLuser quotes is not relevant, because it is perfectly possible to take a jacket and tie off, roll up your sleeves, and be no different from a mobility basis than someone wearing cargo pants and a tee shirt. Indeed, IBM hardware engineers used to have to wear suits, it's what was expected. It's not possible to do this if you are wearing a dress.
In terms of appearance, I would say that standing out is not always a bad thing (I wear collared shirts and a tie even though those around me are much more casual). But do it for the right reasons, not the wrong ones.
Re: The point isn't printing rocket engines...
"...almost, but not quite, entirely unlike tea"
Re: Only one way to disable TPM
My experience with the IBM Security Module (TPM 1.0) on Thinkpads where it was optional was never good.
Once a Thinkpad had been booted once with the security module installed and turned on, removing it stopped the machine from working. Completely. It just sat and beeped at you 16 times when you powered it on.
The only way to revive it was to plug the removed module back in. It had to be the one that was removed. One from another machine of exactly the same type did not work. You could not even disable the security module and then remove it. The IBM maintenance manual stated that if you got a machine to repair in this state, without the original security module, the fix was to replace the motherboard.
More modern Thinkpads, like most machines, have it in the supporting chipset, so it is impossible to remove.
Re: Swings and roundabouts.... @El Andy
just don't use your disassembler in the US. There's clauses in the DMCA specifically banning reverse engineering.
I'm also interested in your disassembler. Are you that fluent in x86 machine code? Can you really gleen from the executed code what the software writer was trying to achieve without access to the meaningful variable names, structure definitions, function names (missing if the symbol table has been stripped), argument types and comments? If so, you are in a class of your own, so much better that anybody else in the world (and yes, in my time I have tried to do exactly what you suggested, and even had some limited success)
In order to get access to what Paul Crawford wants, you would need a de-compiler which was able to reconstruct the C, C++ or whatever language the various parts of Windows are now written in, including removing all the optimisations that not only change the generated machine-code, but in some cases completely eliminate sections of code. And you had better hope there is no self-modifying code in there anywhere!
If you have such a de-compiler, you should be immensely wealthy, because what you would have would be tantamount to magic.
Re: Just when you thought it couldn't get any worse..@AC 11:23
and then review your comment.
It's now 10 years old, but lays down what Trusted Computing means to Microsoft and other vendors.
Re: This @AC 11:40
IBM never nearly went bancrupt. They had plenty of money washing around even in their darkest days in the mid '90s.
It suited them to have a few bad year's results so that they could take some large tax write-downs and not get hammered for their extensive employee shedding exercises.
If you go back to the published results from the mid-90s, and read between the lines, there was still profit being made, money and assets in the bank. It's just that their transformational restructuring costs could be counted as a loss as far as the bottom line was concerned. IBM has some very skilled financial engineers.
Anybody who thinks that IBM is anything other than a quiet giant should look at their share price. Investors are confident, and IBM has irons in more fires than any other IT company. It's just that companies like Microsoft and Apple in particular have inflated value because of various flavour-of-the-month products. I would trust IBM to still be around when Apple have run out of ideas and the PC wave is over and Microsoft are just a patent troll.
And to think I used to think that IBM were the enemy! Either they've got better, or I've just mellowed.
Re: This is a clear violation of copyrights @AC 17:27
Indeed it is, but it is not the EFF that is at fault.
Liberation Music is clearly trying to nullify the fair use clauses in US copyright legislation, and that is a clear violation of the rights permitted by that legislation.
People who think that all use of copyrighted media should be licensed and paid for do not understand the benefit to the copyright owners that such limited fair use, as long as it is not abused, can grant to a work.
Many tunes that would have sunk into obscurity have had life breathed into them by being included in a viral video. The fact that someone can hear something, like it, and immediatly buy it from iTunes, Amazon or such is of huge benefit. So what you want it your music included at low enough quality, incomplete, or with other noise over the top so that it cannot be ripped from the video, but recognisable enough to be identified.
Such was the use in this video. Liberation Music are harming the work and copyright owners, not helping them.
"Although the fact Lessig retracted his counter-notice..."
I think the post by vagabondo above sums it up very well. Go and read it.
Although Lawrance Lessig is a Harvard professor, he's probably not in a position to defend a copyright infringement claim without somebody backing him up financially (american law is very expensive, and although he is a Professor in Law, he's probably not qualified to defend himself in court without professional representation). If this had been a free lecture for Harvard, then the University might have done so, but this was for Creative Commons, and they are probably not cash rich enough to assist.
What gets me is the fact that Liberation Music believe they have any chance of winning. If anybody understands DMCA and copyright law in America, it has to be Professor Lessig. If I were LM, I would be running away very fast, and trying to settle as quick as possible, not that Professor Lessig will allow that now he has decided to get a precident set.
My guess is that LM will lose, and pull up the drawbridge to the US, and never pay the damages. I only hope that if this happens, the US court will attempt to extradite the board of LM to the US. If that happened, a little bit of my rapidly diminishing respect of the US court system would be restored
Re: 32K- the BBC Micro's most annoying limitation
The basic limitation of the BBC Micro was the way that the memory map was laid out. There was 32KB of the address space reserved for ROMs, normally 16KB for the OS, and 16KB for the Basic, or whatever sideways ROM you were using. This was at a time when Sinclair has all of their OS and Basic in a16KB. This only left 32KB without some address-trickery for RAM.
The segregation of the OS and sideways ROMs was a great feature for speed, and allowing separation of the OS and other packages, and really allowed you to do a great deal. The architecture allowed you to have 'service ROMs', essentially add-ons to the OS to handle interrupt driven hardware (the OS could bank-switch the ROMs to handle interrupts), which meant that you could add things like floppy disk drives, mice, teletext adapters, software sprites (Acorn's Advanced Graphics ROM), sophisticated music hardware and even networks and hard disks relatively easily.
With one of the ROM positions populated by static RAM (there were several side-ways RAM boards, mine is an ATPL board with a write-protect switch) you could even (dare I say it) load ROMs from disk. I got the Acorn ISO Pascal Compiler (two ROMs, one an editor and runtime, and the other the compiler) running in a single 16KB bank of RAM by re-vectoring the OSCLI ROM bank switch vector, and loading the compiler from floppy or Econet and then swapping back at the end of the compile.
The BBC OS was a masterpiece of good software engineering, and with the associated Advanced User Guide, which mapped the OS and rest of the system out like a blueprint (and even contained a board schematic), enabled magical things to be done.
When the B+ came along, Acorn copied what Solidisk and Watford had done as add-ons, and moved the 20K graphics screen and some of the low memory pages used by the sound, floppy disk, and other queues into "shadow" memory in the address space normally occupied occupied by the ROM and OS by bank switching, meaning that the low 32KB above 0x700 (I believe, it was 0xE00 on a normal model B without additional filesystems) to be used for programmes. The Master 128 took this even further by adding bank-switched ROM images as standard. "Shadow" screen memory generally broke programs that directly manipulated the screen bitmap without using the OS.
Of course, if you wanted the full 64K of memory, the you could have bought the 6502 Second Processor, which not only gave you a lot of mode-independent memory, but ran at a screaming 3MHz. Playing Elite on a BEEB with a second processor and a Bit-Stick attached gave you smoother full mode-1 four colour graphics (without the screen-tearing divide between the two colour mode 4 and four colour mode 5, something the Electron version could not do because it was missing the interrupt timer used to switch modes at the appropriate position), but also gave you incredible control of the ship!
I always thought that the 64KB claim of the Commodore 64 was a swizz, because the first thing it did when turned on was copy the OS and Basic out of the ROM and into RAM, effectively leaving you with only 39KB (if I remember properly) for any programs, and it did not have the high resolution modes (640 pixels wide) that allowed you to do 80 column text, which enabled us to use the BBC as a terminal to the minicomputers at the Polytechnic where I worked at the time. On the C64, you could use something approaching the full 64KB, but only if you wrote the whole thing in machine code, and disabled Basic.
The BBC Micro also had a ULA, so Acorn were not treading new ground. It appeared to be a troublesome technology, because as far as I am aware, everybody who used them had production problems.
The ULA on my issue 3 BEEB always overheated on warm days (cue the freezer spray), and I noted that on issue 4 and onward, passive heat-sinks started appearing on both the ULA and the Teletext chip.
It seems strange nowadays to have a system that did not have a single fan in the case, and as a consequence would have been silent if it had not been for the incessant buzz of crosstalk interference from the speaker. I suppose the silent end of computing has gone to tables. At least they owe a legacy to these machines.
Re: persistability Doesn't Matter @Matt re:foreign subsid
The point here is that the subsidiary is subject to the law in that country they are established in, as are all of the employees working for the subsid (even those who may be US citizens while they are in the country). The US owners may be free from the effects of the local law, but the local employees certainly aren't.
If this wasn't the case, companies like IBM and HP would never get UK Government contracts with organisations like the MoD or GCHQ, yet they obviously do.
Having worked on Government projects with personal data involved, I know that data security is drummed into the local workers, as is the fact that they personally are liable to prosecution should data in their control be leaked. I'm sure as hell I would prefer the wrath of an employer rather than a jail sentence if I were asked to copy data across a national border.
Ban 3D printers?
And vacuum and injection moulding machines as well?
It's well within the realm of your average senior school metal/woodworking/craft shop to fabricate some very convincing and well made devices without using a 3D printer. It's just a bit slower, needs some reasonable skill, and you can't distribute the model data over the Internet as data. But you can still send the dimensions and blueprints.
Re: @DougS: @M Gale @AC 17th Aug 17:52
The way that the 40 bit addressing works on a 32 bit ARM is by the use of segment registers allowing you to offset the virtual address space for a process into more that 4GB of memory. It's not new technology, and has been a cornerstone of the instruction sets of processors since the mid-1970's.
The first architecture I saw address extension done was the 16-bit PDP-11, which had it's address space stretched from 16 to 18 and then to 22 bits in different models. I do not know the ins and outs of Intel's PAE, but I suspect that it is something similar. The Power processor family also does something similar for it's virtual address space, although it does not need it to stretch the address space. Most other modern processors (those designed in the last 30 years) do something similar to support virtual addressing (but not necessarily for address extension).
The basic method involves breaking up the virtual address space into chunks called segments, and then adding a real-address offset to the base address (normally designated as a page number) in the address decoding hardware. This allows a process to see a linear address range scattered over a larger possibly non-contigious address space. The impact to the code-writer is ZERO. There is nothing that needs to be done for a user-land process to cope with this technique. All multi-tasking OS's have done this for what seems like forever.
It does make the OS have to a bit more work every time you start or context switch a process (it has in some way to manipulate the segment registers - it's different in different architectures), but it's well understood what needs to be done, and has been a standard technique. And it is perfectly possible to write the OS itself to work in a virtual linear address space (an example was the 32-bit AIX kernel running on 64-bit RS64 and later Power processors), where the OS is in control of manipulating the segment registers for itself, as well as for all of the other processes. The 32-bit kernel could manage 64 bit processes, with more than 4GB of real memory on the system, which when I explained it used to puzzle people for whom the 32-bit to 64-bit migration in Windows seemed like a huge deal.
The major limitation to this is although the system may have more memory than the size of an address, it can only be used in chunks determined by the width of an address. So for example, an individual process in an ARMv7 with 40 bit LPAE can only address 4GB of the address space, even though the architecture will support 1TB of real memory. But of course, you can have more than one process, allowing you to utilise all the available memory. And as a side effect, you have the ability to share pages across multiple processes for in-core shared libraries, shared memory segments, and memory mapped-files.
This is not even a problem for the OS, because all the writers have to do is to keep at least one segment free, and then manipulate the segment register to allow the OS to see any of the real memory. Of course, it can't see all of memory at the same time, but it can get access to any of the memory.
The issue of whether 64 bit addresses will add any more inefficiency over 32 bit addresses is all to do with whether half-word aligned load and stores can be done natively. On some architectures, performing a half-word operation (for example a 32 bit load or store on a 64 bit machine) requires loading an entire 64 bit word, and then masking and shifting the required part of the word to obtain the correct half word value. This may be microcoded, but in some architectures had to be done by the program itself. This is slower, and on some architectures, the decision about whether to 'waste' 32 bits of memory verses the performance costs of half-word operations was a difficult decision.
I would have to research the ARMv7 and ARMv8 ISA to know whether this is the case, although I would welcome someone in the know to provide an answer.
Whether floating point load or store operations can be done in units other than the word-length is different from architecture to architecture. For example in Power 6, it was necessary to load a floating point value through a GP register (or two in the case of a double-word FP value), and then move it to a floating point register. For Power6+ and Power7, it is possible to directly load from memory to a floating-point register, allowing you to do double-word FP loads (128 bits) in a single load operation. This decouples the FP processor from the natural word size of the CPU.
Cadbury used to produce a bar called "Bar 6" which was a similar confection, but with 6 "bars" rather than fingers. Terrys also produced a two fingered wafer in chocolate bar called Riva.
There have also been numerous supermarket look-a-likes for ages, of both the 2 and 4 fingered variety.
I was sad when the writing on the top of each finger changed from Rowntrees to KitKat, although recently I was happy that Cadbury returned the Chocolate Cream confection to the Fry's banner again. Just waiting for the same to happen to the Crunchie.
Was the recent limited edition 5 fingered KitKat an attempt at a trademark landgrab, I wonder?
Re: I'd buy that @ObSolutions
Tell me, how do you attach a ST-506 or ST-412 drive to a modern machine? You can't even plug in the ISA controller card into any machine built in the last 10 years or so.
I mean, even EIDE and SCSI are disappearing rapidly.
Re: Is there a Gerry Anderson fan around? @Annihilator
So you are saying that the physics of aerodynamic flight is not natural?
Is there a Gerry Anderson fan around?
If you ignore the lack of a vertical tail fin, the configuration looks uncannily like Zero X, or maybe a little like Fireball XL5.
Were the model designers at APF prescient, or knowledgeable beyond their time, or is there some plagiarism involved. Or maybe there is just a natural way of doing these things.
Just put a boundary network device with a sniffer, something like a Linux firewall. Allows you to record all IP traffic flowing through it using something like tcpdump. Doesn't need any antenna.
I kept reminding my kids that I could, if I wanted, see the URL of all web pages they visited and a lot of their other traffic over the household LAN (can't do much about 3G, but that's another story). Made them much more 'net aware. I know that they could obscure the data using encryption or a VPN, but this would actually achieve part of what I want them to do, and that is to understand what it is to be on-line safely.
For the record, although a lot of the URL and connection data the data is kept on the Firewall for months, I've never felt it necessary to snoop on them (although I have used the data to prove I could, and also to resolve bandwidth contention between them). It's amazing what being open about what you could do can achieve, without actually doing it.
Re: If I were to get a phone for my kid
My 'phones all filter down to the kids as I upgrade the phones, although I gave each of the kids their first phone at whatever age they started spending significant non-school time out of the house, normally early-mid teens. First phone always low end, low value phones, often hand-me-downs on PAYG to give them a means of calling-home, never as a means of keeping tabs on them.
Currently my daughter is waiting for me to replace my Sony Xperia Neo so she can have it, and her Samsung Galaxy (one of the low end ones which was my first Android phone) will then go down to my youngest son, which will replace his Nokia clamshell. This will mean that everybody in the household except my wife will have smartphones, and she just doesn't want a mobile at all.
Eventually, the low end phones just end up sitting in a drawer as 'spares' (like my old Nokia 7110, now really only kept as a curio). The exception is my Palm Treo 650, which I am keeping as my active spare (with a PAYG SIM in it), because its not that desirable to anybody who was not a Palm user, and I like it too much.
The only real thing that bugs me is how soon service provider locked Android phones stop being updated by the service providers. My oldest son noticed this, and as a result always buys SIM-free phones (he's old enough to have his own money to spend) that get the updates direct from the phone manufacturer or Google, not waiting so see whether the service provider is prepared to package the updates. Maybe SPs should be forced to admit that they will never update old phones, and allow them to be un-branded so stock ROMs can be installed on the phones without hacking them.
- Vid Hubble 'scope snaps 200,000-ton chunky crumble conundrum
- Bugger the jetpack, where's my 21st-century Psion?
- Google offers up its own Googlers in cloud channel chumship trawl
- Windows 8.1 Update 1 spewed online a MONTH early – by Microsoft
- Interview Global Warming IS REAL, argues sceptic mathematician - it just isn't THERMAGEDDON