| All | Electronics | Software | Security | Personal | Scouting |
Fri, 10 Apr 2009
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Years ago, I built a simple PIC programmer that I use for programming the micros I use for my various projects. Recently, I was playing with a simple PIC18F4455 based board that had FORTH in rom. Just my cup of tea. Unfortunately, the programmer let me down by not correctly writing into the EEPROM. Having consulted the Microchip programmers manual, I have modified the devices.cfg file that is used so it correctly reads and writes EEPROM. Attached is a zip file containing the software, as well as the schematic for the programmer. It is placed here as a backup in case the originals go away. If you are the rights holder, and you want them gone, then just let me know
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Having said many months ago that I would post the doco and binaries online - and having now received 2 requests in as many months, I have decided to upload them here. Attached to this post are copies of the 65FRx Development ROM (for a 2764), and a PDF file containing the original articled that described the forth board - Which I purchased from Energy Control in the mid 80's.
One minor Note - The rom I have here is v1.5, and there is an anoying issue with the floppy disk routines - prior to use, the disk buffers are located in a memory area that is outside of real RAM on the RSC board, therefore you MUST execute the following command before any disk routines will work. HEX 1800 MEMTOP If you are the copyright owner, and you are sadened that I have posted this information online, then I would appreciate it if you were to email me. Happy to remove the data - but, please keep in mind that I suspect that this is probably the final resting place for this information, and I am confident that there are individuals who would appreciate it if you were to make it available.
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After what seems like forever, I have finally obtained all of the silicon and associated hardware to build my very own ELF computer. What is an ELF you may ask - Well - it is a single board trainer that first appeared ina magazine called "Practical Electronics" in about 1976. It is based on a RCA microprocessor called an 1802, has about 256 bytes of memory, and uses switches to manipulate the address and data busses to load software. I first saw one about 15 years ago, and decided that it simpy wasn't practical to obtain the parts to build one - Well, thanks to the power of e-bay I obtained the hex displays, memory and CPU. A bit of scrounging around in my various parts bins nettwe me the rest of the components I needed, and a couple of evenings of effort later, and - Here it is. My first program was a program to turn on and off the 'Q' LED based on the state of the input button - Gosh, Wow - Gee wizz. Hmmm - Can I get an OO language for it
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Today, Sian was officially awarded her Grey Wolf.
For those who do not know, in Australia, the Grey Wolf is the highest award you can earn in the Cub Scout section. It is the equivalent of the old Yellow Cord. She was one of 12 other recepients within the ACT for the last 6 months. I am soooooo proud of my girl. Here is the obligatory pic:
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I have just encountered an interesting article on Diebold voting machines. For the Australian's that don't know, Diebold make an electronic voting machine that is used across the USA to count elections. If we are *really* lucky, here in the ACT, we will get them soon as well, as we know that Electronic Voting is the only way to go (tm).. There are unfortunately a couple of *minor* problems, most of them are too technical for non-technical readers to understand, but one problem that has just surfaced is that the locking mechanism that is used on the machine to keep it closed uses *exactly* the same key as come computers, and vending machines. Even the same key number. One researcher remembered seeing a key just like it in a previous job, and sure enough, it was the same. It turns out that these keys are extremely common!!!! Here is the Article All I hope is that when the Australian Government decides to rattle down the Diebold voting path, that they employ some people with a clue to perform the security analysis of the solution. Until then, stick to the good old Pencil and Paper! |
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Sounds fair enough to me. Google is complaining about people using the term 'Google for it' as being a general replacement for the term 'search'. In reflection it is not unexpected. Once upon a time there was a company called BIRO who made pens. Unfortunately, the integrity of their trademark has been compromised because everybody calls Pens Biros. Linux had a bit of a kick in the teeth recently as well, as they decided to try to trademark their brand after it was generaly used. I wish Google luck in their quest to modify basic human behaviour. But keep in mind that there is a little bit of data available in the Australian Trademark Office - Google have only applied for a trademark under classes 9, 38 and 42. under trademark law, you have to specify the range of goods and services your mark applies to. This is to prevent name space conflicts. eg Ford have a trademark relating to cars, but not to hot beverage containers. I thought it would be prudent to list what was included in classes 9, 38 and 42: Goods & Services Class: 9 Computer hardware; computer software including computer software for searching, compiling, indexing and organizing information within individual workstations, personal computers or computer networks; computer software for electronic mail and facilitating workgroup communications over computer networks; computer software for creating indexes of information, web sites or other resources Class: 38 Providing electronic mail and workgroup communication services Class: 42 Computer services in this class, including on-line personalized information services; information extraction and data mining; providing access to proprietary collections of information; creating indexes of information, web sites and other information sources; providing information concerning a wide range of text, electronic documents, databases, graphics and audiovisual information Keep in mind that this list does not include the following products you may see on the shelves shortly:
Remember, you saw it here first... Isn't IP law silly (Kind of like genetic or software patents)... |
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Wo Hoo!!!! Last night at cubs, Sian was awarded her Grey Wolf. She has spent the last couple of months finishing her Gold Boomerang, and making sure that she had completed the other requirements, and on Saturday, she finished her hike, so she made it. Peta also finished everything for her award, and Sian and Peta wanted them to be awarded simultaneously. So it is official, Sian and Peta are the second Grey Wolf holders at Lake Tugg Sea Scouts. I am soooo proud of all of the girls, well done Next, they will be invited to a special presentation from the ACT chief comissioner.
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On Saturday, Sian took the cubs from her pack on a grey wolf hike up Mt Tuggeranong. It was a great walk, and the hill was surprisingly steep in places, but the cubs had a great time. Here are some photos.
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Wo Hoo. Megs now has a new bike - a blue 2006 Kona. It is a nice single track mountain bike, with disk brakes. Possibly, even better than mine. - Though she does not yet have a touring arse shaped seat!! Megs is very excited, as this bike has gears (Which is a first for her). I am very proud of her achievements. We picked the bike up on Tuesday, and on Saturday, she rode with Sian and myself to Tuggers (about 10.2km return). Today, after church (Where I played flute again- cool), we both rode from home back to church for a cell group leaders meeting. (About 15km return.) We are now aware of our legs and various other portions of our anatomy. But it is fun.
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Well, today, we are packing for Suzy's wedding. It will be a great celebration. Being a male of the species, I operate under the simple color rule as mentioned above. "Blue and Green must never be seen". Well, you can imaging my concern when Catie pulled out a green shirt, and a blue tie. Well, the only way of solving the problem is to go to the Internet. There was a helpful page on somebodys blog, but Cate dismissed that as being an unreliable source. Well, we all know that Wikipedia is the one true source for all things on the Internet, so I looked there. Hmmm There was no mention... Hmmm... I can fix that I thought, and within about 60 seconds, Wikipedia was improved to support my argument. Wo Hoo. Here is the proof. Wow, my first Wikipedia article.
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Well, I finally decided to auction off a phone I decided that I do not need. I have been a happy ebay purchaser for quite a number of years, and have now entered the ranks of seller - Da Da! You wont believe the last 2 days - On day 1 - I initially put the auction up with a buy it now clause - and within an hour, somebody decided to purchase it - Wo Hoo - Unfortunately, it was a Mary Smith, with an account created that morning, living in the USA - Well, I calculated the fedex shipping charge as $135 AUS, on top of the $500 they wanted to pay, and sent off an email. I get the following response - Hi, I would like to pay for this item via Bank Transfer, you know my address is in US,but right now i'm in Nigeria,i was sent there on a Business Trip,and i want to give it to the Head of the Department as a gift, so i will like to know if you can ship it to Nigeria,i dont mind paying any amount for the shipping cost,pls if you can do this for me i'll be very grateful.if you accept kindly send your full name and account detials which am going to send it to.
Well, let me guess - An American, living in Nigeria, Just created an ebay account for dear little me - Gosh - Wow - I can't believe my luck - I just have to tell them my bank account details - << NOT >> I sent them a response that indicated that I believed that they were Dirty Nigerian Scammers, and relisted the auction - In 7 days, ebay will refund me the $8.00 listing fee. - The relisting was without the buy it now option. Next day, I discovered a bid - Yay - Looks like I might be selling the phone.. I also discovered a number of questions - All telling me that I can purchase similar crap from their ebay store. - Hmmm. And finally, it looks like I am now receiving about 3 random text emails from russia every couple of hours. - I wonder what those are. Right now, I am using them to teach my spam filter what spam looks like Yay! |
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Today, we had a construction night. Lots of time was spent learning knots and lashings. Then we built a catapault. Tons of fun was had by all. We used light weight balls, so no injuries hapened when people were hit. We also has a game where we had to hit a target on the floor. Here are some photos so people can build their own.. Thanks to Jackala for the ideas.
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After tons of effort, and making a compass trail over the sleepover weekend, tonight Sian was awarded her Gold Boomerang at Cubs. The next step is for her to complete her Grey Wolf. Well done Sian. I am very proud of you..
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Cate was a member of the Trinity Christian School debating team today when they participated in an ACT wide debate on various aspects of sport and their place in society. The event was run by the Legislative Assembly PR people, as a mechanism to introduce students to the techniques of parliamentary debating, so it was not a traditional cut and thrust debating event. I was soooooo proud of her when she spoke. I thought the entire Trinity team spoke very well. Surprisingly (for me), I was impressed with the Speaker of the Assembly (Wayne Berry), as he spent the entire day with the kids chairing their debates. In fact, when he spoke, he provided usefull insight into the subjects that they debated. Wo Hoo! Here are some pics - Sorry, I didn't take my trusty SLR digital, I had to resort to the phone...
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Years ago, I worked for the Patent office, well actually it wasn't called that, it was called the Australian Industrial Property Organisation (AIPO). But, because nobody could figure out what Industrial Property was (and, no it wasn't real estate for factories.) they decided to change their name to IP Australia. That is clearer, isn't it. But I digress, I was about to talk about digital Cameras.
Anyway, at the Patent Office, I was heavily involved in a document imaging project that used a massive 450Gb disk array to provide copies of abstracts to patent examiners for their day to day examination functions. This disk array was in a 19" rack cabinet and had a StorageTec tape silo attached to it to ensure that the data was backed up, which it was. In fact, there was a team present to ensure that it operated correctly. We stored data as Tiff files to ensure readability later, and all was good in the land of document imaging. Now, we move to the present day . I purchased a Cannon EOS 350 digital camera, and it is amazing. As a suitable replacement to my aging, but still superb Canon AE-1, it is brilliant. For the first time in years, I can take photos with no obvious consequences, just delete the ones you don't want, and all is right with the world. No more paying $30 - $45 to get a roll of film developed, and the pictures are so portable. I can email them, crop then for the web site, email then to the newsletter editor for the local scout group, etc, etc, etc. But some quick math, and a little thought, suggests that there may be a problem looming. Under my bed is an old suitcase that contains all of the photos (and negatives) I have taken in the 20 or so years I have owned a camera. That is relatively secure, and is not subject to loss through a disk failure. So far, I have over 8 Gb of data amassed in the 6 months I have owned the camera. What is about to happen to my storage world? Am I able to ensure that there are no circumstances where the 16Gb / year I am probably going to use gets dropped onto the digital floor? I am confident that the mirroring strategy I have used will help, but I am also sure that Mr and Mrs Joe Average don't run mirrored servers, and have a backup strategy in place. And that's just the tip of the iceberg. What happens when the imaging or data storage standard changes. As an avid CP/M enthusiast from years ago, I have all sorts of storage devices, ranging from 8" floppy disk through to the Amstrad 3" floppy, through to a stringy floppy. Not to mention all of the data I have amassed on cassette tape. (Yes, I know that the data on those mediums is being compromised with age, I am working on digitising everything, but that adds to the digital problem). With storage formats and mediums changing over time, much of the worlds historic data being created today is probably under threat. Returning to Mr and Mrs Joe Average, I am pretty sure that they don't change their storage formats to ensure that their data is secure. At least the media that is my old photos is fairly secure, at least until I die. How shall I protect the new material? Well, I have recently discovered the art of scrap booking. I think that may be a significant part of the answer. But, don't let that plan detract from the long term strategy of purchasing more and more disk storage. Remember the one who dies with the most toys wins ;-) |
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I would never have believed it... These guys have written some software for the 8088 CPU, and a CGA card that shows an original PC could display full motion video - including sound. Here is the link - www.oldskool.org/pc/8088_Corruption Clearly this was done without a windoze front end.. So it begs the question, where would we be today if the operating system of choice wasn't so heavy.
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This weekend in Australia, we celebrate the birthday of the Queen of England. In actual reality, we have no clue about when she was born (look it up on Wikipedia...) but don't let that stop you from having a holiday. We went on a pilgrimage to Megan's Mum's House in Numurkah. The drive down was uneventful, staying overnight in Holbrook, and getting there before lunch on Saturday. Double demerits apply during this weekend, so we have a real incentive to not get booked. And the boys in blue were out in force - good on them. Maggie arranged for Megs and me to stay in a very nice Bed And Breakfast on the new highway (As it turned out, the B&B had just been sold, so we were the last customers). In all it was a great weekend, just spending time with family. I have attached a large swathe of photos that Cate and I have taken, showing typical sutff we saw on our trip. Megs really enjoyed the oportunity to catch up on her reporting for school. We also got to speak to Suzy, and her wedding is on 22 July at the registry!!! Wo Hoo!!!
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Cool, Sian just showed me a wonderfull helicopter that she has built using Magmax magnetic pieces. I think that it is the first complex model that she has built since she got her first set in France for Christmas. She just tried to tell me that it was the 'only' thing in the book. I'm sure that we can find other designs.
Wo Ho!
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Sian performed in a duet, in a production at the Canberra School Of Music. |
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Well Done! Yesterday, Sian performed in a production called 'Sacred Journeys' at the ANU School of Music. The work was arranged by Lynette Bone and Judith Clingan, and Sian was one of two artists who sang a wonderful duet. The show was really impressive, with a wide variety of pieces, including dance to poetry. All pieces had a spiritual focus, and were very interesting. There was a great write up in 'Panorama' magazine on Saturday, where the work was described as 'Glimpses of the infinite through poetry, Dance and Music.' All at the wonderful age of nine. I am really proud of her! I didn't get any pictures of her performing, as that is not the right thing to do, but I got a great one of her waiting for the performance to start.
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A while ago, I completed a PS/2 Keyboard logger using a simple PIC 16F84, and a NVRAM chip. It was a ton of fun to complete, and still needs a little work. Here are a couple of photos of the device. All it needs now is some heatshrink to protect it. The next step, is to do the same task for USB, but I suspect that it will be more complex, as the USB bus is quite a bit faster than the PS/2 Bus.
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Hmmm,
I just saw a new toolcase that turned up at work. It was a small black binder, containing an assortment of parts that would be usefull for working on PC equipment. The best bit was: ----- That it contained a DIP insertion, and DIP extraction tool, kind of like those we would have used back when memory was in the form of a 16 pin DIP package. Gosh !!!! I haven't seen those parts in years. The bit that scares me is that somewhere in China, a factory is producing these things in bulk.. When Will IT END (tm)..
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Wow Earth shattering information found: " Federal employees pose a bigger threat to private data than the computer hackers most security systems are designed to thwart, privacy officials and lawmakers said. Many agencies are vulnerable to the same type of security breach that occurred most recently at the Veterans Affairs Department, said Pam Dixon, executive director of the World Privacy Forum, a nonprofit group concerned with technology.s impact on privacy. In the VA case, which was announced publicly May 22, a laptop containing names, Social Security numbers and birthdates of 26.5 million veterans was stolen from the home of an employee who was working on a project. " It is about time somebody actually write that down... Here is the link to the entire article: |
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What an old machine! My first job was a summer job working for the School of Biochemistry at the ANU, writing a program for a Toshiba T-300 that controlled a Microplate reader, read the results from the plates, and plotted them. All the code was written in Basic. Essentially, the researcher would fill a tiny sample plate that contained 12 rows of 8 wells with stuff, and the machine would robotically move each cell (under computer control) to an absorption measurement device that would record the transmission characteristics of the sample at a specific wavelength. The data would be shipped off to a computer, and the process repeated for 96 cells. I don't remember the chemistry of what was occuring, but I do remember that the team ws trying to find a mechanism to seperate X and Y chromosome markers in Cow semen, so that a farmer could purchase a test tube containing only cows, instaed of bulls. Interestingly, this research was in 1986, and I saw on the news recently that a major commercial breakthrough had occurred and this technology is now commercailly viable. As a summer project, it was pretty cool, and the most interesting part of the problem wasn't writing the serial code to do the controll, instead, it was writing the plotting software to deal with abritrary scales on the data. The job was finished, and the final payment was a cheque to the value of a Shiny new TRS-80 Model 100 (with 32K of RAM). The ANU could not purchase a machine for me due to asset control problems, but they could make out a cheque. I remember depositing the cheque in mu parents bank, and marching into the Tandy shop, and having to attract the attention of the sales guy, as I surely wasn't really going to make a purchase.(Remember I wasn't 18 yet...) It wasn't long before I discovered that the internal modem only worked in the USA (Using Bell 103 tones, instead of the CCITT standard we use here). I spent the time to understand how the op-amp based bandpass filters worked to calculate new resistor values for the CCITT tones. The mod to the modem chip was trivial (change the mode pin from Bell to CCITT, but the bandpass filters caused me grief for a couple of weeks. The second mod was to allow the device to supply (or recieve power) along the serial cable (using pin 13 from memory), so I didn't have to carry around extra cables. And finally, I modified the light pen interface on the side to accept an Atari joystick, and replaced the proprietary Expansion ROM connector to allow me to use normal JEDEC standard parts. Those were the days - You could get the rom dumps, and make the changes yourself. I have also found my TRS-80 PC1 - Never did any hardware hacking with it, as the doco wasn't available, but have found that he full doco is available now. Just don't have the time available now days!
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I was referred to a story by Mikal that puts into words all that we have been seeing here on the news... That the opposition party here (Labor) does not want a nuclear power plant. http://www.abc.net.au/news/newsitems/200605/s1646199.htm> (See story Here). The bit that Mikal neglected to bring to the attention of the world in his post was that Our Labor party actually isn't a Labor party in the true sense of the word. They are closer to being conservative, and are probably breaking some Trade Practices law by operating under the Labor party sign. All of those good votes from those sheep who have ALLWAYS voted Labor. Come to think of it, the current ALP here is operating under the same ethos, they are not the true ALP I know of the 1970's who would shut any public health fund without even thinking. They are, of course, happy to sell of any public infrastructure they can, as they believe that a buck in the hand is better than a hydroelectric scheme any day!!! In any case, it is a moot point, because the opposition is so far in opposition, that they have started launching debates in the House of Reps in inappropriate places - such as trying to replace all of the words after 'that' in the phrase "we would like to vote that the bill be read a second time....". OMG! Anything to get airtime in the house. They certainly won't win any votes, because they dont have the numbers. My point.... Well, I'm getting to that... Why do the opposition even bother talking, when it matters not? While they continue to meander down the path of enlightenment they are currently going down, all of the votes directed to them by the sheep who have always voted that way, are being negated by the votes being given to the ALP by the similar sheep. Until they do something that causes the voters who consider each parties issues on their merit to vote for them, then all is lost. All is lost... All is lost! On the whole nuclear front, it is very interesting to note the overall cost of developing a Solar Cell to the planet, is considerably higher than the amount of energy it will ever return. In spite of focused research over 30 years, this hasn't changed. It is about time we looked at alternative technologies. Just don't make it it my back yard!!! How about we start turning off the lights in the kids rooms when they aren't there, and turning off the PC's when they aren't being used. Gosh... |
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Well, I finally gave simplog the flick. PHP is simply not serious enough to use for a web site. I am now using Blosxom, which is a 'do it all yourself' environment. At least there are lots of examples from others, so it isn't hard. It is also statically generated, so the kiddies can finally go and get stuffed. If you agregare from me, you may like to point to index.php20 instead of rss2.php. love Doug |
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I thought I would put up a couple of pictures of a computer system I constructed in about 1987. A company in Queensland called 'Energy Control' distributed a single board development card based on a Rockewll FORTH chip (65F11 / 65F12). Essentially the development system had all of the required support components to support develpment (even a FDC). I constructed my unit is a small enclosure, and originally installed a 720K 3.5" drive that I borrowed from tech. Tech wanted their drive back after a couple of months, so I installed a 80 track 5.25" drive. 4 years ago, I decided to replace the 5.25" drive with a 3.5" unit. The 65F11 is an interesting device. It had a 6502 core, and all of the forth primitives in mask rom, as well as I/O controllers all on chip. Many fun hours were spent developing forth code on this system, and I eventually used it to develop my multi radio controller as a tech project. It used the 65F12, which had tons of I/O. I still have all of the doco rom Rockwell, as well as the binary images for the Rockwell forth development ROM, If anybody is interested, I'll post them online.
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I was cleaning the workshop the other day, and found my old acoustic coupler from the mid 80's. Those were the days, collecting dial up numbers for systems that would answer. The cut and thrust of guessing passwords, and trying standard admin accounts (especially on VAX boxes.) From memory, I received my first formal warning when the system admin of our school looked at the teletype records that were printed whenever anybody dialed up (yep, I didn't know about that *early* logging technology.) All at the blistering speed of 300 baud. At least it was battery powered, so the whole thing was portable. Those of you with a clue may ask 'But the TRS-80 Model 100 was well known for it's internal modem... Why did you have to resort to an acoustic coupler? ' Well, 1) Originally the internal modem of the TRS-80 was set for Bell 103 tones, not CCITT (The component changes hapened later on, and yes, it worked a treat, and 2) The acoustic coupler worked a treat in public phone booths..
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Both Otama and Oxley packs have been busy constructing some brilliant Kub Kars over the last 2 weeks. On Saturday, we had the first Kub Kar rally here in Canberra. The turnout was brilliant, and everybody involved had fun. Both Otama and Oxley packs were represented in the finals, which is an amazing effort. Here are some photos. I'll supply more to our magazine editor, so that they get published. Congratulations to Sian, Sam, and Megan from LTSS for being finalists.
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Otama pack were busy building Kub Kars over the last 2 weeks, here are a few cars that I took photos of. We all had a great night on Tuesday tuning our cars for the KubKer Derby on Saturday.
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Here are some photos I took at the KubKar Seeonee earlier this year |
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This is the track and some sample cars I saw. Great effort.
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I have just read a slashdot thread that indicates that Microsoft employees are likely to loose ADMINISTRATIVE RIGHTS! The simple tradition of each employee being responsible for their own desktop software set, and having admin rights, seems to run deep for Microsoft employees.
Now I understand why windows is so unmanageable without admin rights. None of the people who design the systems are subjected to the same controls that hundreds of millions of users have to put up with. Why on earth did they design a product, and then fail to use it in the way that they designed it? Here is the link: http://rss.slashdot.org/Slashdot/slashdot?m=5621 |
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I saw an interesting thing this morning when an authorised Dell service engineer turned up to do some waranty work on one of the stuffed laptops. The laptop in question had a faulty DVD drive, and the PCMCIA eject button had fallen off. We logged the service call yesterday, so the service is extremely prompt, and the tech that arived was friendly enough. He had all of the appropriate spares. The faulty laptop was then disassembeld in it's entirety to replace the motherboard, on the coffee table... WITH NO ANTI STATIC PRECAUTIONS. The tech was wearing a large wollen trenchcoat, and was probably charged (it's a dry environment here..). When I were a lad, we used wrist straps, and everything was grounded. Either (1) things are no longer static sensitive, or (2) he was slack. We should know in a couple of months. |
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I have encountered a good article on 'Reputational Risk" at it-analytics.com.
http://www.it-analysis.com/business/content.php?cid=8503
In the past, I have worked for some companies that would have benefited from having a read of this article. Chris T - I strongy recommend you have a read.
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In August 1981, the IBM PC was launched into the unsuspecting marketplace. The major claim to fame of the design was that it was tried and tested (remember that the 8088 was released in about 1978), and it is probably fair to say that the design on the IBM PC was extremely conservative, as it was a rapid development project to provide IBM with the capability to compete against Apple Computer.
In the olden days, memory was a big deal. It was expensive and complex to manage in hardware. The IBM PC did not use the latest available memory technology when it was introduced; instead, it used 4116 chips from about 1974. 1974! I hear you say. Yes, the original IBM motherboard had the capacity to be shipped with 16Kb installed on the motherboard (expandable to 64Kb), using exactly the same memory chips used in the TRS-80 Model 1 from 1974. The original motherboard could support 64K on the motherboard, and could also support three 64K expansion memory cards, providing 256Kb in total. Remember that in that era, 256Kb was a big deal . the motherboard also had a cassette interface to allow data to be recorded onto tape. Because the IBM PC used 4116 (16 Kbit x 1 bit) dynamic memory devices, a -5v power rail was required to provide a bias current for the memory chips. A suitable power supply was specified that provided +5v, -5v, +12v and -12v for the system to cater for the memory requirements. Here is where it gets silly - We stopped using the -5v rail after 4164 chips (64kb x 1 bit) were common, but the brain dead, thoughtless, engineering involved in duplicating the IBM PC didn.t notice. Modern ATX power supplies still provide a -5v supply rail for these obsolete memory devices. But what about analogue cards you may say? In those cases, they use a -5v regulator off the -12v rail. All of those components being installed into boards, to supply a function that is not required. All because the original design was .conservative., as IBM wanted to get to market quickly! What a waste! |
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The call for papers for the 2006 e-crime and computer evidence conference has been extended to 22 May. From their web site, it appears as though they are yet to choose a theme, but they are interested in any of the following; * Technical aspects of data recovery and analysis * Technical aspects of network and/or internet investigation * Legal apsects of investigation, prosecution or defence * Criminological studies, theories and issues * Use of computers in court * Use of computers to support other investigations Looks like it would be a worthwhile conference to attend. Here is the link: http://www.ecce-conference.com/ |
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I have just loaded up the RS485 controller PCB I designed a couple of years ago.
Here is the link http://www.drj-electronics.com/projects/articles/4in-4out/index.html |
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A blast from the past... I remember in about 1987/88 spending *hours* typing in the source code for a version of Fig Forth (Z80) so that it could be adapted to a STD Bus based card I helped develop for the Electronics Unit at the Research School of Electronics at the Australian National University.
As a card, it was kind of neat - 32K of eeprom space, and variable ram (remember 28 pin JDEC pinout parts). The source code for the project is here; http://www.drj-electronics.com/projects/software/figforth/index.html I have included the CP/M test version that I used to play with. It runs under any of the curent Z80 emulators (Joan Riff, etc). To compile it, you will need a cross assembler called A80Z. It had a unique syntax. Gosh, that has rattled some brain cells. |
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Today, I came across an interesting variant of 'Yet another linux boot disk' (YALBD) This one is aimed at forensic investigations, in environments where the players have corporate credit cards, and limited time in their lives. http://www.forensicbootcd.com/ It looks like a nice product from the supplied advertising, but I suspect that unless I part with some cash, I am unlikely to get to play with it. |
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Spoke to some other Cub leaders last night, and they too are building tracks. Nobody seems to be building track timers.
Progress note - The basic design of the timer is finished. Just have to get it down on paper, and cut the code. As far as the basic hardware goes, it is trivially simple. |
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Projects - Some of my projects
DRJ-Consulting - A site focused on saving energy. we Just Dont Talk About That - A site for sharing funny family stories. Megan's weblog Email me at doug@stillhq.com |
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