In wacky tech news headlines this week, John Deere, a General Motors company, and the world’s largest manufacturer of tractors and farm equipment, has said that farmers don’t “own” their tractors, because of ECU code. Sure, we pay for their vehicles. But we don’t own them. Not according to their corporate lawyers, anyway. In a particularly astounding display of corporate delusion, John Deere told the Copyright Office that farmers don’t own their tractors. Because computer code snakes through the DNA of modern tractors, farmers receive “an implied license for the life of the vehicle to operate the vehicle.” It’s John Deere’s tractor, folks. You’re just driving it.
Several manufacturers recently submitted similar comments to the Copyright Office under an inquiry into the Digital Millennium Copyright Act. DMCA is a vast 1998 copyright law that (among other things) governs the blurry line between software and hardware. The Copyright Office, after reading the comments and holding a hearing, will decide in July which high-tech devices we can modify, hack, and repair—and decide whether John Deere’s twisted vision of ownership will become a reality.
Seeing as all modern CANBus vehicles, not just tractors, have computer code running through their Controller Area Network (CAN) control units, for things like the traction control, stability control, ABS, fuel injection, and throttle control (drive-by-wire) systems, this latest news sends shivers through me, as I regularly modify ECU fuel maps on buses and cars, to a professional standard.
Like the license terms for Windows and many software packages, you don’t own the software, but you own the computer it runs on, that should apply here by default, it’s stupid greedy corporations getting attention to themselves, again. Be realistic, how many farmers are going to modify the ECU code in their tractor, or even care that it’s there? It’s unheard of. They’re running a business, not practising hacking. I’ve never heard of a vehicle owner modifying fuel maps or control unit code, as it requires specialist tools, not to mention knowledge, to do, so John Deere are just being stupid, and I love General Motors, driving Vauxhall cars in life, they’re cracking motors.
It makes sense to John Deere: The company argues that allowing people to alter the software—even for the purpose of repair—would “make it possible for pirates, third-party developers, and less innovative competitors to free-ride off the creativity, unique expression and ingenuity of vehicle software.” The pièce de résistance in John Deere’s argument: permitting owners to root around in a tractor’s programming might lead to pirating music through a vehicle’s entertainment system. Because copyright-marauding farmers are very busy and need to multitask by simultaneously copying Taylor Swift’s 1989 and harvesting corn? (I’m guessing, because John Deere’s lawyers never explained why anyone would pirate music on a tractor, only that it could happen.)
Haha, but what about SAFETY, John? The modifying of vehicle code by an amateur can lead to DEATH, and ACCIDENTS. Hasn’t really bothered anyone till now, though, has it, Deere? CANBus has been around since the 80’s, too, you don’t see, “Man causes pileup and mass death by modifying car software!” in the headlines? Nope! Seeing as most electronic devices like TV’s, microwaves, phones, and even remote controls have software in them, this could open up a massive debate, as you are still classed as owning those.
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I found this picture while looking through Kana’s KanaPhotographics shoots for new material, updating the site, and my heart melted. This is what makes a real Superwoman in my eyes. Kana shot this picture at ComicCon three years ago, and there’s a really heartwarming story behind it:
This little girl had got lost from her parents. She found Superwoman, who came to her rescue, and took it upon herself to be responsible for the girl, and proceeded to babysit her, whilst they looked for her parents. Superwoman kept her safe the whole time, even posing for pictures with her. The little girl was really at ease with her hero. They both found the girl’s parents, who rewarded her with £200, which Superwoman then donated to a children’s charity. A real human superheroine!
This is what really makes me wish Superwoman really existed, and ladies like the one here really deserve to wear her costume, she’s a real life superheroine in my eyes. A really big heartfelt “Awwwww” is in order. If I ever see this Super Goddess at a convention in the future I’m taking her to dinner, she deserves a medal, and lives up to her idol’s standards 🙂 I can see that little girl following in her footsteps someday when she’s older, becoming Superwoman at a convention, rescuing a little girl herself.
Awwwww, it’s what real humans are supposed to be like. I idolise Superman, and try to be the same as he would, except without the superpowers. Looking out for neighbours, rescuing lost kids, looking after women, animals, and helping the elderly. It makes me tick, even out of my costume and cape, it’s what I feel a human should do, look out for fellow humans, even if it means putting yourself in danger 🙂
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Electric showers are great, but they do go wrong occasionally. At Kitamura we repair all types of showers. A lot of people seem to confuse “power showers” with “electric showers”. They aren’t the same. An electric shower simply heats the water, the water goes through the shower under simple water pressure itself. That is where power showers differ. They still heat the water, but they also have a motor assisted water pump, which acts like the turbocharger in an engine, where a little amount of pressure is converted into massive pressure by an impeller.
We recently got called out to a faulty Mira Essentials electric shower. These were made in 2000, and this one was suffering from random pressure drops, and weak output. Here’s a shot of under its cover, I’ve labelled its parts which I’ll explain below:
A. Water input w/filter
The cold water input, with filter. This is a gauze filter that filters any silt in the water. If not filtered out it could collect in the water heater, and cause failure, or blockage in other parts of the shower system.
B. Water impeller.
This is not electrically assisted as in a power shower, but it helps to keep the shower running if there is momentary pressure drop due to something else being used in the water system like a tap.
C. Power and Temperature knob with flow solenoid
This is the ON/LOW/MED/HIGH selector, which works in tandem with two microswitches, and two heating elements. When the shower is switched on, the electric flow solenoid opens, allowing water flow. In the LOW position the water heater is fully switched off, and the water is cold as all microswitches are open. In the MED position, one microswitch is closed, so one of the elements is active, and in HIGH both switches are closed, making the heater operate at full wattage, in this case 4.2kw.
D. HIGH microswitch
This is the microswitch that operates the second element by turning the temp knob to HIGH as above.
E. Temperature knob.
This works by varying the amount of water that gets through to the output. By reducing the speed of water flowing through the heater, it makes the water hotter, and increasing it makes it colder. If the Mode selector is HIGH and the Temp knob turned all the way to HOT, the heater would be shut off by the TCO (Thermal CutOut) on the heater as the water temperature is too high, which will cause scalding to the person using it, and also damage to the heater.
F. Neon indicator PCB
This board contains the neon indicators for Power, Overheat, and Low Pressure. It also contains resistors to prevent premature wear of the neon bulbs, they are run from 240v and don’t last long, especially the POWER indicator, as that is on as long as the mains is on.
G. Mains input terminal block
Self explanatory, this is where the mains is wired in to the shower. In this case the shower had its own switch and fuse in the consumer unit, so we didn’t have to turn the electricity off to the customer’s entire house while we worked!
H. Water heater with TCO (Thermal Cut Out)
Here’s where the water is heated before going to the shower head. The two elements are individually controlled by the microswitches previously mentioned in C, controlled by the MODE knob. The heater contains a thermal cutout so that the elements are turned off if the water gets too hot. Once the water reaches a certain colder temperature, the thermal cutout switch turns the elements back on.
The thermal cutout is normally only activated if the temperature knob is on HIGH, and the TEMP knob set to its hottest, which is minimal water flow, as mentioned in E.
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A customer recently booked her Samsung TV in for repair with us, saying it was clicking, and not actually coming on. I’ve had this problem with an old Toshiba plasma of Kana’s over at White Tiger Martial Arts Academy, it was clicking badly, but actually worked, with visible distortion on dark scenes. In that case though, it turned out to be the plasma panel itself stressing the supply, as we couldn’t source a panel at less cost than the TV it had to be written off.
LCD’s though are much easier to source, and will never actually stress a high voltage supply as they themselves only run at 5v DC on their LVDS bus, so once we’d picked the customer’s TV up from her house, we took off its cover, and took a look. It turned out to be one of our most common problems: Bulging capacitors! Except these were high quality Korean Sanhwa ones. Once you get the cover off (just 12 screws, no plastic clips unlike Vestels!) you’ll see the PSU on the chassis. It uses a massive flyback transformer and opto-isolator for SMPS feedback, to power the backlights. If you thought flyback transformers died with CRT’s, you were wrong!
Follow this procedure to remove the supply:
CAUTION: WAIT at least 30 minutes if the TV has been plugged in. If you are experienced in electronics you can discharge the main filter capacitor using a resistor, if not, leave it unplugged for a while before continuing, and have a brew, thinking about how you’ll proceed, and make notes. I find cuppa-plan time to be very productive, and it keeps me safe, even as a professional. There are high voltages present that can KILL!
1. Remove all connectors I’ve coloured GREEN. They have tabs on them which you must push as you pull the connector. DO NOT pull them out by the wires, you’ll rip the socket off the board and damage the socket pins, making this cheap repair much more expensive.
2. Unscrew and remove all screws I’ve coloured RED, and put them somewhere safe. Remove the board by lifting it by its EDGES, not by a transformer or capacitor, or any other component. Place the board on a suitable workspace, with plenty of room, and an antistatic mat. SMPS supplies contain surface mount components and controllers which are easily damaged. Simply walking on a carpet generates 70,000V which we can only feel as a slight shock as there’s hardly any amps, but that is more than enough to wipe semiconductors out!
3. You’ll notice near CN801 there’s a bunch of capacitors, and some of them will likely be bulged, or have actually vented. If any vents have burst, you must clean the electrolyte off as soon as possible, as it’s corrosive to the board and other components. I generally replace all output caps if any have become damaged, as they will have been stressed. On my board there were 2ea 2200uf capacitors that were bulging. Remove the old capacitors ensuring you don’t overheat or damage the copper pads/tracks on the circuit board.
CAUTION: Take care to ensure you install the new capacitors correctly. They are polarity sensitive. The board and capacitors will be clearly marked which way they should be inserted. Shorted or polarity-reversed capaitors can EXPLODE and/or damage other parts of the circuit.
You should check and if necessary replace any adjacent capacitors that are rated 10V as these seem to be the ones more likely to fail. In my case I also replaced the 1000uF capacitor. Capacitors, contrary to misconception do not have to look visibly damaged to be faulty, they can be internally dried out.
NOTE: If replacing the capacitors does not resolve your symptoms you may need to replace the EEPROM chip on the main board as it can be corrupted or damaged by the power cycling. This will need to be done by a professional as the software contained in it can be TV specific.
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This past week, Warren Buffett’s Berkshire Hathaway agreed to buy the Duracell brand battery products division from Procter & Gamble. Though primarily known for its alkaline batteries, Duracell also makes NiMH and lithium rechargeable products. Some analysts speculate that the deal could have broader implications for the power technology industry.
Some analysts say the acquisition of Duracell by Warren Buffett’s Berkshire Hathaway could have implications in the areas of wireless power
and electric vehicles.
For example, wireless charging is one technology that could see a boost. The new investment may accelerate Duracell’s plans to place PowerMat charging devices in Starbucks coffee shops, which number more than 21,000 worldwide. Another area of speculation revolves around Berkshire Hathaway’s investment in the Chinese electric car maker BYD and the possibility that this deal could be a way for Duracell to expand into batteries for vehicles and the power grid.
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This is my Download Dreams torrent, which contains original purchased videos, and some I captured from VK.com and YouTube, many of which are no longer available. All are in folders based on where I got them from, and all have screencaps. It contains solo girl mudding, girl-girl mud wrestling, and one wetlook video
Captured VK Videos
I wanted to preserve the as-is quality of the streamed VK.com videos, so I used a hardware Elgato HD capture device on HDMI loopback on my laptop. VK do not allow downloading of adult videos off their site, so this was the best way to capture them, rather than using buggy software capture utilities, which 99% of the time don’t work.
Any lagginess in the videos wasn’t my fault, I captured them as-is using my Core2Quad Extreme gaming notebook. I cut the DownloadDreams starting idents off, as they get annoying!
Friends In Mud – Anna & Dominique – 720p HD.mp4
Jodhpurs, Riding Boots & Mud – Stefanie – 480p SD.mp4
Jodhpurs, Riding Boots & Mud 2 – Wiebke – 480p SD.mp4
Mud Commando – Juliane – 1080p HD.mp4
Mud Girl – Juliane – 1080p HD.mp4
Mud Jogging – Irina – 1080p HD.mp4
Mud Mistress – Joyce – 1080p HD.mp4
Mud Wrestling – Wiebke vs. Livia – 720p HD.mp4
Muddy Dress – Michaela – 1080p HD.mp4
Muddy Leather Outfit 2 – Skylar – 1080p HD.mp4
Muddy Mountain Bike Tour- Iveta – 480p SD.mp4
Muddy Sports Shoes – Michelle – 1080p HD.mp4
No Way Out – Iveta – 480p SD.mp4
Playing in Mud 1 – Iveta – 480p SD.mp4
Playing in Mud 2 – Iveta – 1080p HD.mp4
Riding Breeches in Mud 2 – Dominique – 1080p HD.mp4
Sweet & Muddy – Lenka – 1080p HD.mp4
Trapped In Mud – Livia & Wiebke – 1080p HD.mp4
The YouTube videos were downloaded with KeepVid, and are no longer on the site. They are not original quality and have other user watermarks on them.
Mud Wrestling – Iveta vs. Marketa – 720p HD.mp4
Mud Wrestling – Iveta vs. Susana – 720p HD.mp4
Sweet Muddy Blonde 2 – Matti – 1920 x 696 HD.mp4
The original videos are purchased from DownloadDreams, and are original quality as downloaded from there. Each video has a matching screencap file, I’ve left them off the list for clarity. The 480p SD videos were never shot in HD as they are older videos.
Blondes in Trouble 2 – Iveta & Dominique – 720p HD.wmv
Desperate in Mud – Susana – 480p SD.wmv
Fun in Mud – Michaela & Nikol – 720p HD.wmv
Mud Bath – Nikol – 480p SD.wmv
Mud Soccer – Iveta & Lucie – 480p SD.wmv
Muddy Jeans – Stefanie – 480p SD.wmv
Red, Hot & Muddy – Courtney – 720p HD.wmv
Schoolgirl Wetlook – Tiffany – 720p HD.wmv
Stuck in Mud 2 – Irena – 720p HD.wmv
To download the torrent, use these two options: this
Hash value: 71cc9c3578af283dd24ffb513a34eaf80d3f38e8
Magnet Link: Click HERE
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I’ve had this problem a few times on my laptop. It occurs mostly when the power suddenly goes off and it switches to battery. You lose all capacity monitoring, and can’t tell how much is left. The system tray icon changes to this:
Microsoft’s forums are hilarious. Their “Most Valuable Professionals” give the funniest canned cut ‘n’ paste responses, from, “Your power driver is corrupt” to your “Windows needs reinstalling!”. I know exactly what causes it, and it ain’t anything to do with “power drivers” or corrupt Windows. It’s the little monitoring chip in the battery. Like a lot of integrated electronics, it sometimes gets confused. Sudden switchovers from mains to battery tend to cause it, especially if there’s any surges from the battery as it kicks in.
The age old advice of “Reboot!” is the wise advice. If that doesn’t cure it, turn your machine off, remove the mains and battery, and hold your power button down to discharge the circuitry in your device (apart from the RTC circuit, but this doesn’t matter), that should cure it. Removing the battery opens the circuit to the sensing system in the battery, and resets it.
Simples. I hate MVP’s, they go on a 5 day course and think that gives them a Professional title? I’ve done MVP courses, but have the skills and years of software and electrical experience to further and back them up
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Hope everyone has a scary one, and gets lots of treats (willingly, don’t go biting anyone!). Superwoman Jen has even made a pumpkin with scary looking teeth. He’s supposed to be smiling, but still looks scary:
Kana’s made a rather spooky Evil Superwoman costume for this year. The S has blood dripping off it (actually cut out like that, not just splashed with fake blood), the top of the diamond has horns, and there’s blood all over the cape, and her exposed tummy, legs and boots (I get to cover her with fake blood, heehee!), and she’ll have fangs in.
I’m gonna just squirt her with the stuff, like she’s just bitten someone’s carotid artery 🙂 She’s still finishing it off for tonight, so no pics yet. Way to turn a gentle comic heroine into a bloody murderer, Kana 😛
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They say looks can be deceptive, they certainly are with our new heroines Silent Assassin and Black Widow! You should all know by now I’m a stickler for girls in capes, and also a girl in a tight catsuit, either Latex, PVC or leather, and also girls with swords, especially Asian babes. We need some Oriental feistiness to take down the evil heroines, don’t we?
Suki – Silent Assassin
Well, first of all I’d like to introduce Suki as Silent Assassin, our Samurai wielding heroine in a very skimpy PVC outfit who has looks as cute as a kitten, but the heart of a pissed off lioness when she’s in battle, and she ain’t afraid to get dirty, wet or gloopy:
That’s Kana’s real Samurai sword, luckily it’s in its holster as it’s really sharp! Suki knows how to handle it unsheathed too, like Kana does, so you’re safe even when it comes out, unless you’re the one she’s aiming for, your head will roll, literally (ewww!). Any sword fight scenes will be done by Suki and Kana, as they’re our two professional Martial experts, and first aiders 🙂 One thing Silent Assassin HATES is evil superheroine clones like Dark Superwoman, so expect her to team up with the good Superwoman to take her down 🙂
Rina as Black Widow
This lil lady is a real sweetheart in real life, but as soon as she dons her catsuit for us, she becomes Black Widow, fighting against the good heroines like Superwoman. She hates good, and wants to help Dark Superwoman take over the world and turn humans into slaves for aliens, so expect big clashes between dark heroines, good heroines and Silent Assassin.
Don’t let that cute babyface and big sparkly brown eyes fool you, she’s deadly with a gun. It isn’t a normal gun, it fires bullets filled with chemicals that hurt good heroines, like liquid Kryptonite, because we all know bullets alone won’t stop Superwoman. When one of these penetrates her, it injects Krypto-venom into the wound, weakening her, leaving her under Black Widows desires…
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Rikky recently bought a 2007 ADL Enviro400 that had the “Multiplex Communications Fault” and “Driveline Comm Fault” lights in the dashboard flashing. She bought it because “her cute nerd can fix it, right?” she asked me in her sweet voice, standing next to the recovery truck. I was flattered, but seeing as the bus wouldn’t even start, I wasn’t sure on the spot. Apparently one day it just gave up on the motorway, the old owners stuck it in the yard, forgot about it, then the company went bust. I simply sweetly smiled at Rikky, and said, “Yeah, sure, hun!”, as you generally do when a sweet girl you’ve known for years (and who is also my boss) asks you to fix something. Except I COULD probably fix it, being a massive computer geek. Vehicle embedded computer systems are as familiar to me as the ones you use in your office. Heck, she’d already paid £150,000 cash for it, which would buy my company shop twice over. Doesn’t sound so much until you think of the price of a house or shop! Unless you think of a modern double decker as a house on wheels, which is possible!
The ignition comes on, all warning lights come on, some go out, as they’re supposed to. Turn the starter knob to “Start”, there’s no rumble, no life from the engine, just the communications fault lights flashing. The engine lights are still solid, as they don’t go out until the engine starts. No ECU fault codes either, and Alexander Dennis buses have a diagnostic switch in the electrical panel behind the driver’s seat that will flash a code via the engine management lights, so no laptop needed! Except there was no code stored, or it had been cleared. Damn. Over a few days of prodding and gently taking apart the interior to get to wiring, using my multimeter, I found what might have been the problem. The system wake signal cable from the engine computer was showing open when the starter was turned to Start. The signal comes from the starter switch, through the IOU (Input Ouput Unit) network, to the engine ECU, which then sends a signal back, to say “I’m awake, and initializing!”, where it then does a self test of its processor, RAM and ROM. If that test fails, the engine warning light flashes and the engine won’t start. Ours didn’t even get that far to do the test as it wasn’t being woken up!
Control units will go to sleep after a few minutes of non-use, they never fully turn off as they are always powered, like your desktop PC in sleep, they need a signal to wake them up. The brain for the engine was in a coma! This is why no fault codes were being set, and also why it wouldn’t start! I spliced and repaired the cable, hey presto, she started! BUT, a few days later, it broke down (on the darn motorway, just like it did for the old owners. The Police had to close the motorway for us to recover the damn thing!
The look that Rikky gave me at the scene saddened me, as though to say “You let me down, the Police had to hold people up because of you! You’re my nerd, why’s it not fixed?”. Aww, my heart dropped, I was ashamed. She didn’t have to say a word! It was fine in my roadtests though! She calls me Nerd affectionately, she’s the only one who says it sweetly! I don’t like anyone else calling me nerd, it doesn’t sound the same, when others do it it sounds patronizing.
This time, though, only the “Driveline Communications Fault” light was on, which took my instincts straight to the Engine ECU as that is the driveline controller! There was also fault code 111 stored, which according to my service manual, simply means “Internal hardware error, engine may die or hard starting” The “Possible no effect” bit was bollocks, a hardware error in the ECU will stop the engine dead as it will literally be brain dead as the injection is electronic as well as other sensors and stuff. Internal hardware error translates to “Self test failure” which is due, to hardware failure usually RAM!
About 5 hours later, under my (borrowed) oscilloscope’s sensitive nose, I found the REAL cause. The ECU’s oscillator was faulty and not ticking correctly. The crystal provides the computer’s heartbeat, so you can imagine what an irregular or non existant heartbeat does to an electronic device like a computer that NEEDS a heartbeat. They base the clock timings of other components on this main tick. 99% of electronic devices have a clock crystal. Humans couldn’t do without a heartbeat, neither can they 🙂 Engine ECU’s often have a second crystal, which the Cummins ISBe4 Euro 4 engine does, to generate clock timings for the injection. I replaced both, just to be safe!
I replaced the crystal, the bus is now running perfectly and has been for the last three days, and I’ve thrashed the engine driving it round the yard to heat the engine and computer up, it was likely because of heat it failed, ECU’s get VERY hot, the whole reason they’re in a metal case 🙂 Rikky’s happy, now her £150,000 investment isn’t scrap metal, I know she always has faith in me, if I fail, I try again and succeed 🙂
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I recently had a TideLog reader, Steve, contact me about his Menvier TS800 control panel, saying the panel was fine, but the charge voltage was intermittent, even with a new battery. A few days afterwards he dropped it off to me, lo and behold, just like the Optima, a worn resistor, under the keypad. Here’s a picture of what it should look like, and where it is located:
The one I’ve highlighted in green, labelled R52, supplies the +ve 13.6v feed to the battery, via D14 to the bottom left of it, which also seems to supply the telephone module terminal block with +ve voltage too. R83, which is the green resistor highlighted in blue, supplies the AUX 12v for PIR’s and such, and 12.6v to the bell.
Check both resistors, and all diodes for continuity and correct resistance, use my band code chart, in the Optima article, by clicking HERE. R52 on Steve’s board wasn’t badly burnt, but the resistor ceramic coating, along with the colour bands, had come off, there was slight burn evidence at the solder joints, and the voltage was stable until the board was under load, once the resistor warms up it breaks down when loaded with a flat battery on the charge rail.
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You’ve seen Sarah as Superwoman, several iterations of her, in fact. We recently acquired a Dark Superwoman outfit, Sarah offered to jump into it for us. After Kana had done Sarah’s hair and make up, there was only one word to sum up her evil-ness. Wow. Take a look, she’s stunning, with lovely sea-blue eyes:
We’ve never had a Dark Superwoman before, but Sarah fits her perfectly, she can be quite feisty. If we pit her against her good counterpart, who do you think would win? Not so much in a messy wrestling match, but just a good old hand to hand combat match? My bets are on pitting her against SuperKate, she’s naturally fit as she’s a fitness trainer for a living. Sarah doesn’t visually look as strong as Kate, but looks can be very deceptive. Evil Superwoman’s costume comes with some different powers of evil, including Kryptonite lasers from both her fingers and eyes, we know what that does to Good Superwoman1 Here’s SuperKate in our 90’s SW costume, look at her Super-fit physique:
You’ve seen her in my replica Superman costume, but she really fits Superwoman, especially her 90’s one showing her fit legs and tum. Pit her against Dark SuperSarah what will happen? You’ll have to wait and see! Vote in the comments, do you want SuperKate wearing this outfit, or my Superman one?
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When a hard disk is manufactured, there are areas on the platter that have bad sectors. Considering that on a 2 TB hard disk there are 4 billion sectors, then a few bad sectors is only a tiny proportion of the total number of sectors on the drive. During the test phases of a hard disk, the platters are scanned at the factory and the bad sectors are mapped out – these are generally called ‘Primary Defects’. The primary defects are stored in tables in the firmware zone, or in some cases the ROM of a hard disk. When you buy a brand new hard disk, you will most likely be completely unaware of these bad sectors and the numbers because they are ‘mapped out’ using ‘translator‘ algorithms.
Modern hard disks use Logical Block Addressing or LBA, this describes the sector numbering system on the hard disk, and goes in sequence
0,1,2,3,4,5,…..n-1,n (where n is the last sector on the drive.
Spare sector pools
All modern hard disk drives have a spare sector pool. This is used when bad sectors develop during the normal life of the hard disk and any newly found bad sectors are ‘replaced’ with good ones from the spare sector pool. This process is invisible to the user and they will probably never know that anything has changed.
How Bad Sector Mapping Works:
There are at least two methods of bad sector re-mapping (or translation) these are P-List and G-List.
- P-list are defects found during manufacture and are also know as Primary Defects
- G-List are defects that develop in normal use of the drive and are known as Grown Defects
There are other defect lists found in modern drives but the principles are similar. For example, you may find a T-List or a Track defect list, or an S-List or System area defect list.
Lets get into how these defect lists actually work, so let’s say we have a small hard disk with 100 sectors and a 10 sector spares pool.
When bad sectors are found at the factory, shift-points are entered into the P-List, if we take the following LBA sequence 0,1,2,3,4,5,6,7,8,9,10 …99, 100 Lets say that Sectors 3, 6 and 9 are found to be bad. When the first bad sector is found, the first part of the re-mapping process will look like this
What happens here is the bad sector at position 3 is recorded in the P-List. The new map now looks like this;
0,1,2,P,3,4,5,6,7,8,9,10 .. You can see now that 3 is where 4 was.
The next bad sector at LBA 6 is now found
0,1,2,P,3,4,5,B,7 and is again mapped out giving 0,1,2,P,3,4,5,P,6,7
When the whole sequence is complete, our final map looks like this.
Because these sectors are mapped out, the user will never be aware that they exist. If you want to look at sector 6, the drive will translate that to physical sector 8. It takes the 6 and adds the shift points to it, +1 for the bad sector at LBA3 and +1 for the bad sector at LBA 6. When the testing gets to the end of the drive, in order that it is of the correct size of 100 sectors, it allocates the sectors from the spare sector pool completely concealing the fact that there are bad sectors on the media. To all intents and purposes the drive looks just like the original as 1,2,3,4,5,6,7,8,9,10. However, our spare pool has reduced in size and there are now 7 sectors remaining in the spares pool.
After using the drive for a while some bad sectors develop the drive takes care of these using a grown defect list.
The grown defect list or G-List is a table containing the location of bad sector defects found during normal operation of the hard disk drive. When a bad sector occurs during normal use of the drive, something a similar process to P-List generation occurs – resulting with the bad sectors being mapped out. The process for G-List mapping out is slightly different. Lets say our hard disk develops a bad sector at the current LBA 6. What happens in this case is first the bad sector is mapped out. Giving; 0,1,2,3,4,5,G,7,8,9,10 .. A sector from the spare pool is allocated in the bad sectors place. We used 3 of these sectors in factory testing, so the next available bad sector is 104 this now becomes mapped to LBA 6 so our sequence would look like this; 0,1,2,3,4,5,104,7,8,9,10
Again, this process is completely invisible to the user and will still look like the original sequence of 0,1,2,3,4,5,6,7,8,9,10
You might ask, ‘why don’t the new defects get added to the P-List?‘ the answer is that if you add a grown defect to the P-List it has the effect of shifting the data up the drive for each sector from the point where the new bad sector is found. If you look again at the methodology behind the P-List it will help you understand this.
Where a G-List entry can help to revive hard disk, if there was data stored in the original sector attempts then usually it is lost. This may appear to the user as a file that not longer opens, or a a program that doesn’t run anymore or some other errant behaviour. This will not become apparent until the next time the file is attempted to be opened. It may also be that it is such a long time since it was opened that a backup plan means there are no backups of the working version. So bear this in mind when developing you backup plan.
Defect Mapping in a live system
When a hard disk is powered up, the p-list and g-list are usually loaded into RAM on the controller card. As requests for data come through, the location where the data is required from is passed to the translator, which makes the calculations necessary so as to determine which sectors to actually read in order to get to the actual data requested. In our example above, if we wanted the data from LBA 6 the translator would first run through the p-list and add 2 sectors to the count for the two bad sectors found at the factory, it then checks this value in the G-list and finds it has been re-allocated to sector 104. It then reads sector 104 and presents you with the data.
All the magic that goes unnoticed by normal people 🙂
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I thoroughly enjoyed Telltale’s comic style “The Walking Dead” choice based game. When the “Wolf Among Us” was announced I was eager to try it. The first episode was pretty good, so a few days ago I decided to buy the season pass.
Big mistake. Upon trying to download Ep2, the system was trying to make me pay £3.99 for the episode, when season pass holders shouldn’t have to pay. Looking on Telltale’s forums was a 3,000 page thread on the issue. Telltale were blaming Microsoft, yet Microsoft were adamant it is a bug in the API in the game, in other words, Telltale’s crap programming. Having done Xbox programming, I understand where the bug is.
When you select an episode for download, from the in game content page, the API is supposed to be told by the game whether or not the season pass is installed, it then hands the user over to the marketplace, if the check for a season pass registers as true, the download should show as free. For some reason the API wasn’t being told about the pass, so the episode was showing at full price.
Telltale then said users who had the pass were supposed to recieve a redeemable code to get the episode at no cost. I never recieved mine, yet lots of people on Telltale’s forums did. Telltale also said that they were putting out a game update in 48 hours. Four days later, the Xbox Live status is still red on the issue, the patch is still not out, and I still haven’t recieved my code. In the end I just re-contacted Microsoft an have obtained a refund for the pass.
Telltale, you should be ashamed. I bet you’ve had thousands of pounds from season passes, yet you can’t even fix a simple API bug like this. You’ve just lost my £10, and I won’t be continuing The Walking Dead Season 2. No more money from me, that’ll teach you to pass the blame. You can’t even make simple games like TWD and TWAU run smoothly, they lag like hell during some scenes, shows how much you really care about user experience.
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In this article I’m going to help you diagnose and identify control problems in your washing machine. Modern washing machines all contain a computerized timer and control system, this is responsible for controlling all the different circuits in the machine such as the sensor network, motor, drainage circuit and the heating circuit. The main thing to remember, whether diagnosing a modern sensor washer, or a car electrical network, is that computers run off the same basic principle. Inputs and outputs, if a computer can’t get a reading or signal from an input, the output can’t happen, either at all, or efficiently, the computer then has to fall back to what are known as “reference values” stored in a ROM. An example of this in a washing machine, is if the computer can’t determine the water temperature, it can’t heat it correctly.
An example in a car would be if it can’t detect how much fuel is being injected to the electronic injectors, the emissions are affected and it has to fall back to reference values stored in “injection maps” in the ECU as it’d be using too much fuel and it would cause combustion problems.
If you suspect that there’s a fault in one of the circuits in your washing machine it’s usually much easier to test all the components in the circuit before suspecting that the problem lies in the control board. Problems in the wiring network of a machine are much more likely the cause. For example in the drainage circuit you would check the drain pump and the wiring; the heating circuit you would check the element, the thermostat and the wiring. If you then suspect that the problem still lies in the circuit board unfortunately it’s usually quite difficult for inexperienced people to test the board and you’ll actually just need to replace it altogether or consult an electronics guy like me.
The first problem we’re going to look at is program issues. Most modern machines are designed to shut down if they detect a fault somewhere in the system and this is usually accompanied by a fault code. A fault code is displayed on the front of the machine as a combination of letters and lights or numbers. These fault codes vary from one manufacturer to another so it can actually be just as helpful to watch your machine to diagnose where the fault is, such as in the drainage circuit or the heating circuit. When you turn your machine on, the first thing it does is to lock the door via the electronic door lock solenoid and it’s then that it performs a self-check. If in the self-check it detects a fault somewhere in the system it’ll shut down and display a fault code, or if the door doesn’t lock properly it’ll also detect that as a fault and shut down.
Once the machine has passed the self-check stage, it will proceed to fill with water through the fill valves (solenoid valves) at the back. Most stages in a washing machine cycle are programmed to complete within a predetermined time so if your machine doesn’t recognise that it’s filled within a couple of minutes it will usually shut down and display a fault code to stop any flooding occurring. Assuming that’s OK and the machine has filled with water it will then move on to the next stage in the wash cycle. Once the water has filled to the correct level the machine will then start to agitate it and heat it if required by that particular cycle. Once the temperature has been reached the machine will then wash for a certain amount of time before draining the water away and again, this has to happen within a predetermined time so if it doesn’t, the machine will shut down and display a fault code.
Once the water’s drained it will then do a short spin and this is followed by the rinse cycle. The rinse cycle is very similar to the wash cycle, except in the rinse cycle the water isn’t heated; water is brought in to a predetermined level within a certain amount of time, it’s then agitated, before being drained away. Most machines have at least two rinses in the rinse cycle and on the final rinse both solenoid valves at the back of the machine open up and flush any conditioner from the detergent drawer down into the drum. Once the machine has completed the rinse cycle it will prepare for the final spin by balancing the load. It does this by attempting to evenly distribute the weight of the load around the drum by using sensors to detect drum wobble on either side of the drum. However, if the load contains a particularly heavy item – such as a pair of jeans or a towel – amongst an otherwise lighter load, it will attempt to balance that heavier item amongst the load. If it can’t balance the load it will simply refuse to spin or it may just shut down and display a fault code.
However, once the load has been balanced the machine will spin and complete the wash cycle. If your machine is dead and it’s not displaying any lights or anything on the front then you’ll need to check it for continuity. Firstly, just unplug it from the wall and have a look at the fuse inside the plug to make sure it hasn’t blown; once you’ve established that it hasn’t, you’ll need to check for continuity between the plug and the control board. Don’t just replace the fuse and plug back in, the fuse has blown for a reason, and until the reason is found and fixed it will likely blow more fuses.
If you follow the path of the plug in through the machine, some will come through to a filter board, it then passes along to the plug on the control board. Grab a multimeter on a resistance or continuity setting and just check for continuity between the two. If you can see that there’s continuity on both connections, that shows power is getting to the circuit board, but there’s probably a fault inside – the way we need to check is by replacing the board with a new one.
Next, let’s have a look at if your machine is blowing a fuse when you plug it in; usually this is caused by a short circuit somewhere in the machine and the short can either exist in the control board or within components around the machine. You can check very easily for a short if you unplug the machine and, using a multimeter on a resistance reading, check for the short across the plug through live and earth, and live and neutral. If there is a short there it’s going to show up as a resistance reading of less than a couple of ohms. Often the first thing to short is the heating element, so try disconnecting that and testing again for a short circuit; if the short has gone then that would indicate that the short does lie in the element. Obviously you can double check by testing the element itself and for a working element the reading you’re looking for is somewhere between twenty and fifty ohms so anything outside of that reading means you’ll need to replace the element.
On the other hand, if removing the element doesn’t get rid of the short the next thing to disconnect is the circuit board and again, once you’ve done that, check for a short there. If the short still hasn’t gone, move further along the line and try checking on the filter board. If the short still hasn’t gone then then it’s likely to be in the plug and the cable and you’ll need to replace those. To test the element, first disconnect the connector lugs and then turn your meter onto a high resistance setting and measure from earth to one of the terminals – from this you shouldn’t get a reading. Then put your meter onto a low resistance setting and measure across the element – on this one I’m getting a reading of about twenty-seven to twenty-eight ohms, so that indicates that this one is OK.
If your machine is tripping the electricity, the process for diagnosing is largely the same, however it may be that a normal meter won’t show any fault being present. In such a scenario an engineer would use an insulation tester such as a Megger and this produces five-hundred volts for determining where the breakdown has occurred. Again, it’s likely to be due to the heater, or heaters if it’s a washer-dryer appliance, but if the tripping is occurring during the final spin the motor is likely to be at fault, where it’s being worked at its hardest during that part of the cycle. One final thing about control boards and tripping faults is that a lot of the time it can be difficult to conclusively diagnose the fault; sometimes a fault that’s being caused by another component actually appears to be caused by the control board. Similarly, if you’re replacing the control board, many of them now require professional programming on installation.
I’m here to help, don’t be afraid to ask!
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