Here I bring out my old PSION series 3a.
A blog by Duncan Large, a 2nd Level Computer Science graduate from DeMontfort University in the UK. Subjects include: Computer Science in general, Programming, Humour, Retro Gaming, Lifestyle.
Wednesday, 12 September 2012
Tuesday, 4 September 2012
The ultimate password safe.
Some researchers have developed a way for you to learn a password (of sorts) and prove to a computer that you know that password, thus that you are you, without actually being told the password.
You can't tell anyone else what it is, because you don't consciously know. It's hidden in a region of your brain.
Here's generally how it works:
They have created a game that teaches you the password, without you ever knowing it.
The game programs a type of memory you have called muscle memory.
What is muscle memory? Well when you learn to ride a bike, for example, you are concentrating heavily on balancing and steering. But after a while, all that becomes automatic. Like instinct. It's the same with walking, you don't need to think about how to walk do you?
That's because your muscle memory has learned it for you. It does all the movements and balancing after a while, letting you concentrate on more impotant things like deciding which way to go and how fast.
Well this game is like guitar hero in that you have to press keys in time with patterns. Some of the patterns are random junk. But others are repeated. These form the password.
As you play your muscle memory gets better at pressing the keys for the repeated patterns. Without even knowing it your brain is being taught to press the keys better and better for the repeated patterns.
Being good at those patterns is enough to prove that you know the password.
You don't give the computer the password. It tests you to see if you were trained with those patterns. All you do is play the game again.
Someone who never was trained with your password won't do as well as you, because thier muscle memory never made them good at your patterns.
Thus you can prove you are you. For several weeks at least.
To try it yourself go here:
Tuesday, 7 August 2012
Documentation!
Today I have learned the importance of keeping record of software versions and usernames relating to remote computers.
On Friday Holland contacted us reporting that their PC, which we configure with our software was playing up. Apparently it was so bad it was restarting as soon as it was powered on.
The machine is what we call a scanstation. Basically its a pc running our software with a scanner attached. Configuring a replacement is not that big a deal, install the correct version of the software and the scanner driver. Ship it out and sort out last bits of configuration remotely.
I had almost done this once I was informed, by chance, that this scanstation also performed its own local processing, meaning that it has its own database and server software.
The people who know how to set one up have left the company. Have they documented anything about what they did when setting this thing up? Have they heck.
No one knows a login for the machine. Without which I can't pop on, look at it, back up the database and restore it all on the new one.
No record of what version of the software to install. Now there are rumours an upgrade had been performed. So any documentation I have found is likely out of date.
We have a support system and a wiki to store this stuff. But it probably just ended up in their heads.
Document everything...
Wednesday, 1 August 2012
About RAM
Well here is a bit about it that I'm sure he will find useful:
RAM stands for Random Access Memory. Simply because a processor in a PC may access any part of it at any time. Unlike in the old days of tape used for storage (old days for non backup use that is, tape is still the best there). Tape had to be wound to the correct position to load or save the data, not random access!
The best type of ram you can get is Static RAM. This RAM uses a type of chip that has the fastest access speed. Yes, RAM has a speed. The processor must wait for the RAM to deliver the goods. Static RAM, or SRAM is so bloody expensive that you will not have much in your PC, if any. I mean a few years ago I could buy a 8KB, Yes 8 Kilo Byte SRAM chip for £3. A gigabyte of the stuff? If I was a government, perhaps lol
So modern PC's tend to use Dynamic RAM, or DRAM. This RAM is much cheaper to make. But it has a downside, its much much slower than SRAM.
This is because DRAM is forgetfull. The data that is stored in it must be automoatically refreshed several times a second, this slows down the access time.
However, DRAM has gotten much faster than its original version. We call modern DRAM memory DDR.
DDR stands for Double Data Rate. To try and speed up DRAM, designers came up with the idea that they could speed it up by letting the processor take or store twice as many bits at the same time as before. So if you were storing 16 bits at a time before, now the memory controller would let you store 32 at a time. So they Doubled the Data Rate :-D
DDR was replaced with DDR2, which increased the speed even more by running faster than DDR and along with a few other changes allowed the processor to store 64bits at a time! Doubling the data rate a second time.
Now my PC is using DDR3 :-D which is the latest version, soon to be replaced with DDR4. DDR2 and DDR3 are common in shops, DDR not so.
Memory prices change every day due to many things including how many the manufacturer decided to make at that time. I remember one time DDR2 was very cheap. Then it more than doubled in price in a week! A 1GB stick of DDR2 RAM went from £25 to £50 or higher.
If you have an old PC that uses DDR and you wish to upgrade, best do so when DDR2 or DDR3 is nice and cheap!
There used to be the idea that adding more RAM speeds up the PC. That used to be the case for something like an Amiga, where more RAM really made a massive difference, but modern PC's have so much that most of it goes unused.
It is true that with too little RAM your PC will be running very slow. Adding more ram will speed it up, but only to a point. Having loads of ram is good for letting you handle loads of data and applications at the same time.
Hopfully Oliver Kelly got something out of that. There is a lot more to it but I dont know all of it myself lol
As a sort of mini interview I asked Oliver what he thought about cheap android tablets, you know the ones from china. We both got one each and have been using them for a while now:
Too be honest. Very very inspressed. The way they take the materials and build them then create amazing rom's and its so cheap and there quite good but the free apps are quite on the downside whats your opinion?
and so I answered:
Well the hardware is quite good. Mine runs at 1ghz, as fast as the my android phone.
They fall down with bad and cheap batteries. Also the original rom may not be the best for tablet use.
I did find a guide that shows how to open my tablet and change the battery. I may give it a go.
Take a look at Olivers blog: relatedtotech.blogspot.com
Sunday, 22 July 2012
My camera died yesterday :'(
Over 2 whole days the entire river and surrounding area plays host to hundreds of thousands of people, fireworks, river events with parades and Viking dragon boat races, several music stages, beer, local and non-local food (mmm the Swedish mango beer was nice), a carnival, flypast and more I will go see later today.
It was at this festival yesterday that I lost a dear friend. My camera.
I love photography, and am a big fan of film. I don't use film at the moment due to space issues but that's changing. Other than my phone I have only 2 digital cameras, a Fuji s8000fd and a Canon HV30 HD camcorder.
I tend to leave the HV30 for filming purposes as it is a camcorder, but it dose take still photos, better than the Fuji tbh.
The Fuji was my first proper digital camera. It was a birthday present from 2007 I think. I have used it at events like the festival, holidays and family birthdays. It also took one of the first pictures of my first newborn nephew.
Its been love hate. I have loved some of its features and hated the lack of, or stupidity of others lol. I never felt it could replace my film slr's. Manual focus was laughable, the electronic viewfinder was useless (viewfinders should be high resolution or optical with digital overlay) and high speed shooting wasn't what I wanted it to be.
However it was very good at macro, brilliant at letting me preview depth of field no matter what the aperture (you can loose so much light with a film camera its difficult to preview) and had a nice flash.
Sad to say I can't use it anymore. Yesterday while recording a demo of some Greek hoplites fighting some barbarians I noticed the image started looking like it was on fire! I knew it was the ccd, but I didn't think much of it as I have noticed funny things before with this camera. This time it was different because the distortion was recorded to the video and still images.
It went back to normal after I rebooted it. For a few mins I got some more video till I noticed more purple fires here and there, the image flickered, the hoplites started to melt into the scene, then it was normal, then it happened again and stayed that way.
Switch off, then on. Same.
Reset all settings. Same.
Take out batteries to try and 'cold boot'. No change.
At home upgrade firmware. Purple fire effect is now orange.
I did some Googling and found that it is a defect that affected many camera years ago. Looks like I was lucky it lasted so long:
http://www.imaging-resource.com/badccds.html
Well, now I can get that D-SLR I was thinking of upgrading to.
Goodbye old friend.
Wednesday, 8 February 2012
Yes sir! I'd like a slice of Raspberry Pi!
Later the computers came with more and more software already written and programming was seen as less and less an important lesson. Kids started learning only how to format spreadsheets and not how to make a game or have
the computer do something that it didnt do before.
This did not stop me however luckily my first computer was a commodore 64. After turning it on it would sit there asking you for programming. All the other kids were moving from such machines to PC's and many never even felt the need to program them. At school the machines there were Acorns running RISC OS. They were fun to play with and hack ;-) but the most fun I had was with the older BBC Model B machine used during german classes. I went on it a lunchtimes, not to learn german but to program it. Other kids used to watch me as I made the thing beep and draw all sorts of patterns on the screen, simple things to me, that to them were like magic.
That all ended. Now some of these machines are sitting here in my bedroom. Turned on from time to time for a little bit of fun. The kids just use windows at school, loading programs that they have no idea how they work, written by the kids who learned to program in school all that time ago.
But some of those kids from that time wish to change that...
Now, from the creator of the best game the BBC computer ever had, "Elite", comes the Raspberry Pi.
The Raspberry Pi is a small, low power (can run off 5v USB or AA batteries), computer running linux with 128 or 256MB ram, USB, HDMI, Ethernet network port and an SD Card slot. Plug in an SD Card with the OS on it, a keyboard, mouse and screen and you have a fully functional linux computer for only about £20. Yes, the most expensive version of the Raspberry Pi will cost around £20!
It is hoped that schools can afford to give these to kids, so that every kid may have a programmable machine that can even fit in a pocket. They can learn to program and hack them using any programming language but Python is supported out
of the box.
I will be getting one once they are avaliable at the end of Feb.
Links:
David Braben, creator of Elite, shows off his Raspberry Pi
The Raspberry Pi project page, and where to buy some Pi
Thursday, 5 January 2012
My TV Died. RIP?
  As a geek who realises that the average TV is just a computer with a tuner and a screen I began thinking "It's crashed" and my first geek instinct was "Reset it". Now that should be simple you would think? Nope.
  I needed to make sure that the hardware was fully reset. The only reset option I could find was to reset the picture settings. I pressed all sorts of combinations of buttons and no luck. I started googling, not much there but user manuals, that I had to pay for lol. I suddenly remembered that most TV's have a service menu where you could calibrate the colours on a more accurate level. Perhaps I can reset in that!
  Further googling found a youtube video showing me how to get into the service menu. I had to put the TV in standby and (this will work on Sony Bravia LCD TV's where the model number starts KDL)
- Put the TV in standby using the remote
- Press on the remote the following buttons: [i+], [5] , [VOL+], [ANALOG TV]
- After a sec a green menu should appear. BE CAREFULL IN TV SERVICE MENUS. You really really can bugger the thing up here.
- Now press 0 and 8
- The TV should reset.
Which it did. :-)
    That fixed the sound for the inputs :-) But the digital tuner still wont work. Looks like it blew and that caused the crash. Good thing the DVD recorder can be used as a tuner!
  Thankyou to the poster of this video:
www.youtube.com/watch?v=1J6w8cHRKu0