Shareware Super Platinum 8

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Text File | 1994-07-24 | 14.6 KB | 278 lines

ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ XMedia Disk media error detect utility (c)1994 Brand-X FreeWare ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ Note: You will need a disk test utility, such as NORTON's DISK TEST (DT.EXE) to complete the media test using this program... There are also many DISK TEST clones out there, so finding one should be no problem. What's it do? ----------------- XMedia from Brand-X FreeWare is actually very simple. All it does is fill every available byte on floppy disks with ASCII 255 (FF Hex). It's setup to be fast and easy to use, operation is mostly automatic. XMedia will generate a 360K (approximately) file called 360K255.FIL that it uses to fill the floppy disk with. If this file doesn't exist when XMedia is started from the command prompt, it will generate it. After you run XMedia and fill a disk with CHR$255, run DISK TEST to expose bad or weak sectors and mark them as bad so they won't fail later with your valuable data in them! READ the following - it's very informative and might save you data... Page 1 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ Theory ------------ As we all know, our data is composed of digital on/off switches. Each byte consists of 8 bits - a binary number, that represents the character value, from 0 to 255, and 1 parity bit that DOS uses to determine if the data is accurate or not. Bits are either on (1) or off (0). I've illustrated the concept below. 8 Data Bits 1 Parity 1 byte--> ⁄ƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒƒø⁄ƒƒƒƒø 1 0 1 1 1 0 0 1 0 Disk surfaceƒƒƒƒø ⁄ƒø ⁄ƒø ⁄ƒø ⁄ƒø ⁄ƒø ⁄ƒø ⁄ƒø ⁄ƒø ⁄ƒƒƒ Disk surface ≥∞∞≥ ≥ ≥ ≥∞∞≥ ≥∞∞≥ ≥∞∞≥ ≥ ≥ ≥ ≥ ≥∞∞≥ ≥ ≥ ¿ƒƒŸ ¿ƒƒŸ ¿ƒƒŸ ¿ƒƒŸ ¿ƒƒŸ ¿ƒƒŸ ¿ƒƒŸ ¿ƒƒŸ ¿ƒƒŸ Bit cells 1=charged (∞∞) 0=not charged One way to think of each place on the disk that a bit is stored in, is as a "cell" that is either "charged up" with magnetism (1) , or not (0). Page 2 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ Data errors occur most often when cells fail to hold a "charge", thus making the byte of data invalid. If *ONE* bit fails - you can lose an entire program, database, or other important file! We can imagine the cell as a glass of water. Cells are not likely to fill up all by themselves, but they COULD "leak" or lose their charge. Whether cells leak or not is determined by the quality of the media. One flaw in the magnetic properties of the disk can make ONE or MANY bit cells leak. They can also have a tendancy to leak over time. So how do we find leaky cells? The first step is to charge them all up! This means we need to write an ASCII character that has the maximum bit cells turned on. There is only one. The last character in the IBM extended character set - 255. By writing this character to every data byte location on the disk, the maximum number of bit cells is turned on. Now all we have to do is wait for a leak. How long does this take? Anywhere from 1 millionth of a second to 100 years! Well, we DON'T want to wait 100 years, or even ONE for that matter - but we DO need to find out if any of the cells leak, or even MIGHT leak in the future. Some people simply say "Just re-format it to find bad spots." Here's why you SHOULDN'T ... Page 3 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ We are all familiar with the format process. DOS writes the format pattern on the disk and "roughly" tests it for errors. Sometimes, it returns the message "xxxx Bytes in bad sectors". When FORMAT.COM finds bad areas, it marks the entire cluster as bad in the FAT tables, so that DOS won't write anything to it. Later, when you write a file to the disk, DOS basically "skips" these bad places, so your data gets written to places that seemed ok at the time of format. Unfortunately, FORMAT.COM can't take the time to wait and see if the cells fail, so if a cell doesn't fail in a very short time, it passes. The result is: formatting/reformatting a disk does NOT find all the defective areas. In fact, if a disk with sectors marked as bad is RE-formatted, it's possible that some of those sectors will hold a charge long enough to pass thru the format process on a subsequent format and be marked as good! People who reformat disks a number of times concurrently to make bad sectors "go away" often have the highest data error rate known to mankind. Summary - DO NOT reformat disks to find bad areas, or erase a disk. Always delete any files and then run DISK TEST. Page 4 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ OK - so lets say that we've run XMedia on a disk, and all the cells are charged up. We need to read the disk and see if any have gone bad. Usually, you can simply test read the entire disk and allow DOS to look for parity errors. These are what causes the dreaded "Data error reading disk X" message. Parity? Huh? The parity system uses an "extra" bit to help DOS spot bad data. The 8 bits in a data byte are totalled up, and the if the resulting number is even, you get a parity of 1. Similarly, an odd result gets a parity of 0. This parity bit is included with each 8 bits of data, effectively making a byte 9 bits - (8 of data, and one parity). Of course this is no guarantee that you'll catch an error, since there's a 50% chance that the total value may remain even (or odd) and still be different than when it was first written. Ideally, we should scan the disk and make sure EVERY character is still CHR255 - later versions of XMedia should be able to do this for you.. for now, let's let a disk test program do the work for us.... By reading the disk, each byte is automatically checked for parity error. DOS does this for us. Run your disk test program and see if anything turns up. Page 5 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ A good disk test program will scan the entire data area, looking for errors. When it finds one, it should remember where it is, and at the end of the scan, offer to mark that area as bad in the FAT tables, just as FORMAT.COM does at format time, so you don't write data to it later. Once an area is marked as bad, it will NEVER be accessable to DOS again, UNLESS you re-format the disk! (DON'T DO IT!) Once we find these areas, we want them PERMENANTLY disabled. If data errors are found, be sure and let the disk test program mark the areas as bad, and do not ever reformat the disk. If you really want to give your disks the acid test, wait a week and then run the disk test again... but DO NOT run Xmedia again! Here's why: Once you have charged up all the bit cells, you want to allow them time to leak if they are so inclined... if you WRITE to them again, it will re-charge them and not allow them to fail in time. One other factor can accellerate this process - HEAT. Temperature plays a roll in how well a material can retain a magnetic charge. The higher the temperature, the harder it is for a material to retain the charge - in fact permenant magnets are made by allowing liquid metal to harden and cool while being surrounded with a strong electromagnet to align all the atoms in the material - and that's what causes a magnetic field. Page 6 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ The ultra acid/hammer test... The worst thing you can do to your disks, beside cut them to pieces with scissors, is to expose them to temperature cycling. Temperatures over 80¯F can greatly accellerate magnetic decay in disk material, and after a few weeks of the normal daily ambient temperature changes, your data can be in pretty poor shape. The test.... Store the disks to be tested for a week or more in a place that sees about 85¯F to 95¯F during the day, and 50¯F to 60¯F at night. The garage is a good place.. protect them from dust tho. This is pretty harsh treatment. REMEMBER!! DON'T run XMedia again!! Run the DISK TEST again, and see if you've turned up any more errors. If you HAVEN'T, you found yourself some pretty decent quality media. Odds are, however, that out of 50 disks from any one manufacturer that passing the format, AND the first disk test, you'll turn up a at least 5 or 6 disks with fresh data errors. These are the ones we really want to find. Page 7 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ Here's some ideas to maximize media reliability... * Never reformat a disk. Always run a disk test program to flag bad spots. * Always store your disks in a cool place - avoid heat. * Run the disk test often, especially after storing disks for a long time, and just prior to writing data to them. * Run XMedia on all your disks, blank or not to fill any available disk space with CHR255 Note - XMEDIA will not overwrite any existing data on the disk. Ideally, you should run XMedia as soon as a disk is formatted, that way the entire disk will be filled. * Familiarize yourself with the sound the disk drive makes when a data error occurs. DOS will retry 4 to 5 times to read a byte before it stops and displays the error. Sometimes, DOS will get the data right after a few tries and never tell you that it had trouble. This is a clue that a data error is inevitable I've included the actual test results that this program is based on.... Page 8 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ How many files do you have on floppy disk? We have thousands. In fact, several gigabytes worth. A study was done by Brand-X on a 2 groups of disks... Group Quantity Type ------- --------- ------------------------------------------------- Group 1 380 720K 3´" disks, that were punched out to be 1.4m From various cheapie no-name brands. Group 2 350 1.4m disks from various manufacturers, including the cheapest no-name bulk disks we could find, all the way up thru brand names like Maxel and Sony. The disks were loaded with shareware and GIF images, etc. - and were completely full, with the possible exception of 1 or 2k of leftover space per disk, if any. The disks were stored for 1 year, and read from occassionally during that time as files were needed.. Data errors were pretty common. We flagged the spots bad as they were found. Page 9 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ Prior to running XMedia on both groups, the 720K group tended to have more data errors than the 1.4m group, We got tired of losing files. It took over 3 months of "spare time" to copy all the files off of each disk, run XMedia, test the disk, and then copy the files back to it. During the copying and testing process, the errors were numerous... 720K Group: 1 error per 15-20 disks, 1.4m Group: 1 error per 30-35 disks. After copying, testing and re-copying all the disks, they went back into storage mode for the following year.. This time we were careful to store them in a cool environment. Disks were read from as needed and NO ERRORS were encountered! Just recently, the entire library has been copied to tape, and the disks liquidated. We kept track of the errors for both groups... 720K Group: 2 errors per 380 disks! 1.4m Group: 1 error per 350 disks. Page 10 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ The tests seem to show two things: 1. Disks become more reliable if the bad areas are flagged permenantly as they are found and not re-formatted. 2. Pre-testing the media by charging all the bit cells and temperature cycling before use yeilded a much greater relability factor. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - It sure worked for us, and a number of other people. Try it - it's free! You can easily incorporate this method by A. Running XMedia on disks as soon as you get and format them. Then just store the disks normally until you need them... B. Run a disk test on the disk each time BEFORE you write data to it. C. When errors ARE encountered, erase the defective file and run the disk test to flag the spot bad. Do not run XMedia on the disk again. Remember - once you fill the disk, it stays there until you write something else over it. Page 11 ÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕÕ Brand-X FreeWare Info / Stuff Brand-X FreeWare is just that: No-Guilt software that's free for the taking. No registration or other compensation is required. If you like this program and want more of our stuff, but can't seem to find it on the BBS's, you can get a floppy (any size) with other Brand-X FreeWare releases by sending 5 bux to: JC @ P.O.Box 1953 Santa Clarita, CA. 91386 Comments / Suggestions are also welcome. Here's more Brand-X warez: PSET - An EZ to use graphics screen draw/CAD (ahem) for CGA. XLIB - Library director for Quick Basic 4.x series. PCIS - Purple Chickens in Space! A funny CGA demo. XS20 - X-Section - cuts up large Binary or text files for transportation on small floppies, then re-assembles them. XJOY - Read and test joystick/game ports 1 and 2. XSCAN - Keyboard code scanner, great for programming references. SCRIBBL3 - CGA screen grafix demo. Sit and trip out. XASCII - ASCII/Hex/Character chart/X-reference for programmers. XSCAM - Screen text capture to file. Resident/and non resident. XLIST - Searches BBS and other text lists for matching data. XBANNER - Create colorful alternating block ANSI messages. XNEBULA - VGA space scene generator/Gas clouds/planets and more. ƒ¬ƒ¬ƒ ⁄¬ø "XMedia" and "Brand-X FreeWare" are Trademarks of ¿Ÿ ¿ƒƒŸ ¿ Digital Imaging