Choosing your computer and CD-ROM drive.Please note that this article will not be updated in the future and is kept for historical purposes only.
1. Jargon
De-mystified.
2. Choosing your computer and
CD-ROM drive.
3. Drives, daisychaining, jukeboxes
and towers.
4. Installing your CD-ROM
drive.
5. MicroSoft
Extensions.
6. General
Maintenance.
7. What to
do if things go wrong.
8.
Choosing a CD-ROM
publisher.
9. Evaluating CD-ROM
products.
10. DVD
Technology.
11. CD-ROM
- The future.
12. CD-ROM resources on the
Internet.
Compact-disc, Read Only Memory. A CD-ROM will commonly hold up to about 660 megabytes of information. The hard disk capacity of an average computer will be in the region of 100-500 megabytes of data, so a CD-ROM can hold about 6 times the amount of data that you can hold on a computer. The CD-ROM is made up of metal disc with a single spiral track on it, into which a hole is burnt or not. A laser is then beamed up onto the disc and depending on whether the light hits a hole or not, the laser is deflected back to the read mechanism, and then transferred back to the computer as a series of 0's and 1's, which is binary, and something the computer can understand. Therefore the data is held digitally and read optically.
A CD-ROM disc will generally have its help and guide files in the centre, index files in the middle, and the data files towards the outside edge.
Where 2 or more external CD-ROM drives are linked together.
A device is an external piece of equipment or hardware, linked into the computer. The device driver is a piece of software which tells the computer how to talk to the device and how to interact with it. In the case of CD-ROM, the device is the actual drive or player, the device driver is MicroSoft Extensions.
Disc means the optical disc, disk refers to the hard or floppy drives.
Disk Operating System. The environment in which the computer works. For most computers, this will be MicroSoft DOS, and the Macintosh equivalent is System 7
Both can be used interchangeably to refer to a CD-ROM reader.
The informal standard that was agreed by CD-ROM publishers and manufacturers back in the mid 1980's. This has now been superseded by:
Which is now the official standard that all CD-ROM discs are produced to conform to.
A CD-ROM drive which can access a number of different discs sequentially rather than concurrently. Pioneer produce the most popular version.
Microsoft's device driver to allow the computer to talk to a local CD-ROM drive.
A combination of written data, pictures, sound and moving images contained on the CD-ROM
Write Once, Read Many. Similiar to CD-ROM technology, the difference being that you can write to a disc yourself, rather than producing a ready produced disc. They cannot be overwritten however.
Choosing your computer and CD-ROM drive.The first question to ask is 'Which PC and CD-ROM drive should I buy?'. The simple answer is that there is no simple answer. There is no 'right' PC or drive to go out and purchase, since you first of all need to define what you want to do, what databases you wish to access, how much money you have available, and so on. When you've done all that, you can make an informed decision about which computer and drive is the best to get for your purposes.
Firstly, do you actually need another PC? Are you able to make use of an existing one? You may be able to move some of your existing applications onto another machine to free up time and space on something that you already have. Bear in mind however, that once your users have discovered the joys of CD-ROM searching, it will be difficult to use the machine for anything else.
What are the basic requirements? This is to a certain extent a chicken and egg situation, because its difficult to decide what requirements you have until you know which products you wish to use. Therefore, you should check the technical requirements of those products, looking particularly at the amount of memory they require, if they run under a particular operating environment such as Windows 95, if they require a colour monitor, speed of the processor and hard disk requirements. As a general rule of thumb, I would suggest the following:
A 486 based machine. This refers to the speed of the processor. A 486 is faster than a 386, but not as fast as a Pentium based machine, for example. Needless to say, the faster the machine, the more expensive it will be. Machines will also have a clock speed on them, which also regulates the speed at which it can work; a 66mhz machine is not as fast as a 90mhz machine for example. Generally however this will not be a specific requirement by software retrieval engines.
A floppy drive; 3.5 rather than 5.25. You'll generally only find 5.25 drives on older machines, since it is now redundant, but if you are using an old machine you may find that one is on the machine. Remove it! Or at the very least, tape it shut so that it cannot be used. Its very tempting to put the CD-ROM disc into it.
A hard disk (obviously). The amount of space required is going to depend very much on the number of applications you intend to place onto the machine. Each different software package will take anything from 4MB to 20MB of hard disk space, so you'll need to do a few sums. In most cases, new machines come with anywhere between 500MB to 1Gbyte of disk space, so that it shouldn't be a problem. Bear in mind however that a common rule in computing is that your hard disk is never quite large enough.
The memory requirements that you have will also depend very much on the applications which you want to run. Ideally, 16MB of RAM will be all that you require, even if you are running Windows '95, but the bare minimum would be, I'd suggest, 4MB. Go for the largest size that you can afford however,. since it means that you won't need to worry about upgrading for some time. To access this amount of memory you will need a memory management system of some sort, although Windows does come with its own.
Monitor. You can't easily buy monochrome these days, but even if you could, I would not recommend it.
I would also recommend a good maintenance contract for the machine, preferably one where the engineer comes to you, rather than you having to send the machine back to base in order to be fixed.
Also, ask yourself questions such as:
How robust does the machine have to be? Is it going to be used on a daily basis for 10 hours a day, or just now and then? Does it need to be a certain size, because you only have a small amount of space - are you going to be better going for a flat desktop footprint, or will you save space with a tower based computer? Are you going to want to move it around a lot, or will it stay just in one place?
This still does not narrow the field very much; its a blessing and a nuisance that there are so many varieties of machine on the market. Of course, you may not be given any choice in the brand or type of machine that you are allowed to purchase, but nonetheless, you will still need to consider the above questions when deciding on exactly what specification to get.
Once you have chosen the PC, you will then need to decide which CD-ROM drive(s) to buy. You will be pleased to know that, as there are less drives on the market than computers, your choice will be much simpler. Again you will need to answer certain questions for yourself - the answers to these questions will point you in the right direction of drive to purchase.
How much do I have to spend? You can spend anywhere from £58 upwards on a CD-ROM drive.
How quickly do I need to be able to retrieve information, and what kind of information is it? Much is made of the speed of CD-ROM drives, in that they are slower than online searching, but if your end users have no online experience, this won't be too much of a problem. If you only require to retrieve textual information, you will not need an amazingly fast machine, but if you are intending to use sound and moving image files, you'll have to have a faster drive.
The three statistics that you should obtain from a supplier are the Transfer Rate (measured in KB per second), the Access Time, (measured in milliseconds) and the Mean Time Between Failure or MTBF (the average time it takes for a drive to break down). The single most important of these is the Access Time, and a fast drive will have a speed of 150 milliseconds. Anything much over 250ms will be a slow machine. You will also see that drives are described as 2x, 4x 8x and so on. This again will give you some indication as to the speed of a machine - an 8 speed (or 8x) is eight times as fast as the first generations of drives, and is faster than a 4x for example. The fastest drives are currently about 10x although a 12x drive is under construction.
You also need to find out how a drive deals with the problem of dust. A good machine will have an automatic dust detection facility, together with a double door system. Some drives will work using a 'Caddy' system, others will work on a 'tray' system. Caddy systems are generally less prone to dust problems.
Find out what you get for your money. The cost of a drive should include the interface card, cables and driver software. Drives which at first glance appear to be cheaper may not have these as standard, and you'll have to buy the various extras on top of the price, which can work out more expensively. Check the warranty period, cost and time taken to repair a drive.
Do you want a portable drive, stand alone, internal, external or tower system? These are discussed in detail in the next section.
Having considered all of these factors, you should be in a better position to make your purchasing decision. I deliberately have not mentioned 'Will x drive work with y machine' since in general they will do. However of course, that is the final test, so make sure that you check this with your supplier.
Drives, daisychaining, jukeboxes and towers.External drives.
These are connected to the computer via a cable, which hooks into the interface card in the computer. They can easily be moved from machine to machine (as long as the machine has, of course, an interface card in it which is appropriate for the drive), its easy to daisychain drives as well. They take up more room than some other solutions, but can be stacked. If they go wrong, its easy to uncable them and return them to your supplier.
Internal drives.
Actually fitting into a spare bay on the computer, which is a little more tricky than just fitting an interface card. Difficult to steal them without stealing the entire computer! Limited to a maximum of two internal drives in a computer, but they can be supplemented by having external drives attached as well. If they go wrong its more difficult to remove them to return to the manufacturer. Many new computers come with an internal drive already fitted as standard.
Portable drives.
Easy to take around the country with you, and with the addition of a laptop machine they can provide you with much greater computing power than otherwise. Tend to be slower than internal/external drives however, and its easier to steal them.
Daisychaining.
The situation where you have two or more external drives linked together by cables, with the first drive being cabled into the interface card in the computer. Most interface cards will allow you to daisychain up to eight drives together, though this may result in a high memory overhead on the computer.
If you wish to hook up more drives to a computer, make sure that they are the same make if at all possible, since it makes the installation of the software and hardware much easier.
The advantage of daisychaining drives is obviously that you have more drives available to you to use, allowing you to do cross database searching (if the retrieval software allows this). You are also in a position to move drives around from machine to machine, and to test to see if a drive has failed. The major disadvantage is that it is more expensive to buy single drives and daisychain them than it is to buy a tower system.
Tower systems.
These are basically internal drives which have been cabled together for you and enclosed in a box. Easy to install - as easy as a single drive. The advantages are that is it is a compact and neat collection of drives, easy to cross database search, reduction in dust problems, since the tower will have a door and lock on it, and they are cheaper than buying four individual drives. Disadvantages are that its more of a problem if one goes wrong (you need to open the tower up and recable the unaffected drives), so you may well have to return the entire unit to your supplier if there is a problem. They can also really only be used in this configuration, unlike a daisychained system which you can break apart and put onto other machines if you need to.
Jukeboxes.
This have a single magazine cartridge into which you can put up to six discs. The entire cartridge goes into the jukebox, which only contains one read head. The advantages are that its cheaper than buying six drives, you can keep discs together in cartridges neatly, they take up less space, and its easy to change cartridges of drives. The disadvantages are that there is a memory overhead, as Extensions assign a drive letter to each 'drive' (i.e. disc) even though there is only one read head. The drive is not the fastest on the market, and it takes time to change swop discs out in the drive. Consequently, a jukebox is not really suitable to put onto a network, except under very specific circumstances.
Manufacturers and prices.
|
Company |
Telephone |
Model |
Disc load |
Speed |
Transfer rate |
Cost |
|
Aztech. |
01734 820840 |
Zeta 8x |
Tray |
8x |
1.2Mb |
£128.00 |
|
Evesham Micros |
01386 765500 |
Panasonic CR581 |
Tray |
4x |
600kb |
£58.00 |
|
Mitsumi |
01276 29029 |
FX400 |
Tray |
4x |
N/A |
£58.00 |
|
NEC |
0181 993 8111 |
Multispin 6xl |
Caddie |
6x |
900kb |
£271.00 |
|
Panasonic |
0900 404041 |
CR5828 |
Tray |
6x |
900kb |
£105.00 |
|
Pioneer |
01753 789789 |
DW-S114x |
Tray |
4 4x's |
614kb |
£3171.00 |
|
Sony UK |
01932 816000 |
CDU 77E RP |
Tray |
4x |
684kb |
£140.00 |
|
Teac UK |
01923 2255235 |
CD-58E |
Tray |
8x |
1.2Mb |
£165.00 |
|
Toshiba (Sold by eg: Koch) |
01420 541 880 |
XM5533B |
Tray |
6x |
900kb |
£POA |
This is simple a very small list of drives and models, but I have tried to make it as comprehensive as possible, and to give a wide variety of types of drive. For a more comprehensive list you are advised to check some of the monthly computing magazines; my personal favourite is PC PLUS
Installing your CD-ROM drive.Having identified or purchased your computer and CD-ROM drive you will need to install the one to the other. This does not need to be a fraught or trying experience, as long as you follow through the installation in a logical and sensible manner, with a degree of confidence.
The tools you need.
The installation.
Backup your system (just to be on the safe side) and take copies of two files in particular - your autoexec.bat and config.sys files. Either copy them onto the floppy, print them out or copy them out by hand. The reason for doing this is that the installation of the software will make certain changes to these two files, and if you have copies of them you can reinstall them should anything happen.
You may need to 'park' your hard disk. Older machines will have a utility called 'Park' or 'Dpark' or something similiar. This ensures that the read heads on the hard drive are moved over an area of the hard disk which does not contain any information. Consequently, if the computer gets bashed, the heads will not hit the hard disk and destroy any information contained on that section. Newer computers will do this automatically.
Turn your computer on, and take careful note of the messages that appear on the screen when you are booting up. Again the reason for this is that when you install the software it will add a couple of new messages to the boot up procedure, and you will want to watch out for these to ensure that that element of the installation has worked properly.
Turn the computer back off again, and have a careful look at the back of the computer to see where all of the leads and cables fit in; make a note of this if necessary. Its an obvious point, but it will save time later on when you come to put everything back into place. Remove all of these, starting with the power supply to the computer. Make sure that you are not carrying any static electricity on you - ground yourself if necessary. This is to ensure that you do not accidentally pass on a static charge to a delicate part of the computer equipment such as an interface card. Identify the screws which open up the case on the computer (this may or may not be obvious), then slide the cover back and off. You should see a number of 'expansion slots' on the motherboard into which you can put your new interface card. There will be a number of cards in there already; controller card, video display card, perhaps a network card or internal modem and so on. Choose the slot that you want to use - any of them should be fine, but I'd suggest a slot without cards on either side to allow you room to work. Unscrew the dust plate behind the expansion card and put it to one side.
Take the interface card carefully out of its antistatic package and hold it by the corners. Push it firmly into the interface slot until it clicks home. Make sure that you cannot see any of the little golden strips at the bottom of the card - if you can, you have not pushed the card firmly home. Once you are happy, screw the card into place. Replace the computer cover (but don't screw it back down just yet) and replace all the cables, monitor and so on. Cable the interface card to the CD-ROM drive (it should be obvious which end of the cable goes into the drive and the interface card - if it isn't, then it doesn't matter which end of the cable goes into which end of the card or drive). Congratulations - you have now done the hardware installation!
The acid test comes when you turn the machine back on. Needless to say, it should work fine, and will boot up exactly the same way that it did before you turned it off. If this is the case, turn it off again and replace the screws on the cover of the PC. If it doesn't work properly, all you will see on the screen is nothing - no boot up messages or anything else. This indicates that there is a problem of your interface card conflicting with another card in the machine. Skip the next section on software installation and go straight to the troubleshooting section.
Software installation.
You should now install MicroSoft Extensions, using the installation disk which came with the drive. This program allows DOS to access the large amount of data on the CD-ROM disc, tells the computer how to talk to the interface card and drive and finally assigns a drive letter to the newly installed drive. It will do this by adding lines to the two files mentioned previously - autoexec.bat and config.sys. At your C:> prompt you will need to move to the A: drive and type either install or setup to begin the installation program. Follow the onscreen instructions (which differ from program to program). Usually you will be asked a series of simple questions, such as the number of drives you are installing and so on. If you are given options, accept the default as given. Finally you will be asked for permission to alter your autoexec and config files, which you should give. Once this has been done you will need to quit from the install program, take the floppy out of the drive and reboot the computer.
Before you do this however, make sure that the CD-ROM drive is turned on, and has a disc in it. When you turn the computer back on, you should see two new messages appearing on the screen - one to say that a new device driver has been installed, and one to say that Extensions has allocated a new drive letter (usually D: or E:, depending on your system) for the CD-ROM drive. and you'll see the little busy light on the drive flash quickly as the computer accesses it to make sure its there. To check that everything has worked properly, at your C:> prompt, type DIR D: (or whatever drive letter has been assigned to the CD-ROM drive) and you should see a list of files displayed on your screen. This will indicate that both the software and hardware installation has worked properly, and that the computer can read the CD-ROM disc in the drive.
If all of this works correctly, the entire process has worked out successfully, and you can breath a sigh of relief. If it has not worked the way it should do, read through the following section on troubleshooting.
Troubleshooting.
That in theory is how the installation works, and 9 times out of 10 that's exactly what will happen. However, sometimes there are little problems with the system and you'll need to identify the problem and solve it before everything works properly. There are only a few things that can have gone wrong, and they are easy to fix, so don't get into a panic and think you've broken everything because you haven't.
The first indication of a problem is if the computer doesn't boot up after you have put the interface card into the machine. This will be because there is a conflict between different cards. Each card in the computer is identified by the computer by using a Port Address (sometimes called an I/O address), and this is set on the card by a series of dip switches or jumper settings. If two cards share the same address the computer doesn't know which is which and refuses to work. Remove the CD-ROM card and check to see what the I/O address is set to, using the manual that comes with the card. You will be able to change this address by flicking dip switches, or by putting the jumper onto another set of prongs on the card. This sounds more complicated than it is, but the literature that came with the card will help you identify what you need to do. Change the settings to another port address and *make a note of the new address*. Replace the card, reboot the system, and everything should work fine this time. If it does not, repeat the process until it does. When you go to install the software, one of the questions asked will be for the address of the card. Rather than accepting the default, you'll need to type in the new address as you have set it.
If the computer boots with no problem, you will see the first message saying that the device driver has been installed, but not the second one saying the MicroSoft Extensions has been installed, with the drive letter assigned to the CD-ROM drive. Check this by doing a DIR of drive D: and perhaps E: and you will probably get a message which says 'Invalid drive specification' which means that the installation of extensions has not been successful. This will probably be because your autoexec.bat file goes straight into a menu system, or into Windows for example, and does not actually execute the line starting extensions. Simply move this line further up the autoexec.bat file, reboot the computer and you should see the Drive letter allocation message appearing on the screen.
If you try and do a directory reading and get the message 'CDR 101 Read Failed Abort, Retry, Fail' it means that there is some sort of hardware problem. Check to make sure that the interface card is properly seated in the expansion slot, that the cables are all correctly in place, the CD-ROM drive is turned on, the disc is in it (the right way up!). If this is all correct, remove the card, and try the installation on another machine. A hardware fault is rarely the problem with the interface card or the cable. Put another disc in the drive, and it should be briefly accessed when it goes in - you should hear a slight whirring noise. If it makes any other kind of sound, its a problem with the drive.
If you still have no luck, don't bother to keep trying - it is unlikely that it is something that you can deal with yourself. Ring your supplier or technical support and get them to look at it.
MicroSoft Extensions.The installation of this software should work without any problems at all, but its useful to have a little understanding of how exactly this software works, and what the lines which are added to your files means.
Installation.
This is in two parts - the device driver for the specific CD-ROM player you are using, which will be proprietary (that is to say, specific to the manufacturer of the drive) and the extensions program itself (mscdex.exe) which is common across all drives. The driver is installed into the config.sys file, and extensions into the autoexec.bat file. Most if not all CD-ROM manufacturers will supply the extensions on their own installation disks, and you will only have to load the disk into the A: drive and type setup or install or some similiar command.
What do extensions look like when they are installed?
The install program will add a last drive statement to config.sys and a device driver line. If you are using a Hitachi drive, it will look something like this:
| device= | \dev | \hitachia.sys | /d:mscd001 | /n:1 | /p:300 |
| [1] | [2] | [3] | [4] | [5] | [6] |
| lastdrive=z |
| [7] |
[1] is the DOS command to tell the PC it has an external device to use
[2] is the name of the sub directory where the device driver has been installed.
[3] is the name of the device driver
[4] is the device name. This must be unique, and the same in this file and autoexec.bat
[5] is the number of drives attached to the computer
[6] is the port address for the interface card
[7] is the last drive statement.
In the autoexec.bat file the line that will added will look like this:
| \bin | \mscdex.exe | /d:mscd001 | /m:8 |
| [1] | [2] | [3] | [4] |
[1] is the subdirectory that the install program will put extensions into
[2] is the extensions program itself
[3] is the device name, the same as found in config.sys
[4] is the amount of memory allocated to extensions. The higher the amount, the better the performance.
Each manufacturer may have a slightly different way of naming the subdirectories, but they will all follow a similiar pattern. You should not need to manually change any of these lines yourself - the install program will do it all for you.
What happens then?
When the computer is booted up you will see it install the device driver first, then extensions, giving you the name of the drive which has been assigned to the CD-ROM drive. If the drive is not on, or a disc is not loaded it may take a little time to do this.
You will then be able to do a DIR of the CD-ROM drive and disc to check that extensions have been installed correctly.
Tricks and traps
The install program will add the lines above as the last line to both config.sys and autoexec.bat files. If you have installed a menu, or another command in autoexec.bat, the computer will go and do as it has been told, without checking back to autoexec.bat until you quit from whatever the application was that you have gone off to use. Extensions will therefore not be loaded until this point, or perhaps not at all. If this is the case with you, simply edit autoexec.bat to move the \bin\ line to the top of that file, and get extensions to load before anything else.
Sometimes for some reason, extensions get installed twice, usually by people who discover a fault and think they can sort it out by reinstalling the software. Unfortunately, this does not work - the problem will be elsewhere, but what you get left with in config.sys is something like this:
device=\dev\hitachia.sys /d:mscd001 /n:1 /p:300
device=\dev\hitachia.sys /d:mscd002 /n:1 /p:300
or
device=\dev\hitachia.sys /d:mscd001 /d:mscd002 /n:2 /p:300
This will then install two device drivers, and you will see a message to this effect when you boot the system. This will most likely cause problems when you go to swop discs, since the computer thinks that you have two drives available, and the retrieval software will be waiting for a disc to be placed in the second, non-existent drive. The solution is simply to edit the offending line to take out the second driver name. Also make sure that you do not have any duplication in the autoexec.bat file either.
You may sometimes find that a program which worked fine before extensions was installed no longer works. This is because extensions is a TSR (Terminal Stay Resident) program which is loaded into memory and cannot be unloaded without deleting the lines in autoexec.bat. If you have other programs which take up a lot of memory, there may not be enough space left to run them. The solution is to take extensions out of the autoexec.bat file and create a batch file to call them when they are needed. A smoother way of doing this is to alter the batch file of any application software to include the line there before going into the software. It would look something like this if you were using the SilverPlatter DOS retrieval engine SPIRS:
Spirs.bat
\bin\mscdex.exe /d:mscd001 /n:1 /p:300
cd\spirs
spirs
cd\
It's also useful to check to see if extensions have loaded sometimes, and you can do this by copying out the line starting \bin\ at the C:> prompt. If they are not loaded, this will load them, and if they are already loaded, you will get a message to say this.
Complications
The above gives you a good explanation of how extensions are installed. However, there will be times when the situation is rather different; if you have several drives, or the port address is different for example.
If you have several drives they can be daisychained together. Check the drive documentation to see how many drives can be linked together onto one interface card; it will usually be seven or eight. If you add more drives when you are first installing the system, simply type in how many drives you are installing at the appropriate point in the installation of extensions. If you add more at a later date, you will need to go into the autoexec.bat file and change the /n: parameter, then reboot your system.
The port address will need to be changed if you have some sort of conflict with other cards in the machine; you will see this if the machine refuses to reboot after you've installed the interface card. You need to change the address on the card using the dip switches or jumper settings and change the /p: parameter to the new address.
If you wanted, for some reason, to install more than eight drives onto one machine you'd have to install another interface card. Once you've put the second card into the machine (making sure you've chosen a different port address!) you will need to edit the config.sys and autoexec.bat files to include a second device driver name (eg /d:mscd002).
Some examples of different CD-ROM drive manufacturers.
Hitachi: See the above examples. However if the machine is an IBM PS/2 model 50 or above, instead of being \hitachia.sys it will be \hitachib.sys. You will be given this option during the install program.
If you use more than eight drives on a PS/2 Model 50 you will need lines that look like this:
Config.sys
Lastdrive=z
device=\dev\hitachib.sys /d:mscd001 /n:8
/p:300
device=\dev\hitachib.sys /d:mscd002 /n:2 /p:340
Sony:
Config.sys
device=sonycdu.sys /d:cdrom001 /b:300 /m:d /t:1 /q:3 /u:2
/it:1 /rc:1
Autoexec.bat
mscdex /d:cdrom001 /m:20
The values in the config.sys file are:
u: the number of drives
attached
t: Inactivity time - the motor of the CD-ROM drive will be turned
off after that period of time has passed
rc: Number of retries for access to
the drive
b: port address
m: data transfer rate (a switch particular to
the Sony drive)
t: related to m: and is a DRQ channel
q: related to data
transfer rate as well
Pioneer:
Config.sys
device=\dev\dexatrm.sys /d:cd-rom /n:6 /c:cdp
Autoexec.bat
\bin\mscdex.exe /d:cd-rom /m:8
NEC:
Config.sys
device=\scsi\cdrom.sys
Autoexec.bat
mscdex /e /d:neccd /m:30
/e loads the driver into expanded memory. This can only be done if you have an expanded memory board on the machine. If you do not, this parameter should be left out.
***** Please note that all of the above are only examples: an actual installation may well result in different device driver names, or sub directories. *****
Config.sys
DEVICE=
<device driver>
/d: Device driver name
/n: Number of drives
/p: Port address
/e Use expanded memory
/m: Allocate memory buffer
Lastdrive=
eg: Device=\dev\hitachia.sys /d:mscd001 /n:1 /p:300
Autoexec.bat file
/d: Device driver name
/e: Expanded memory
/l: Drive letter
/m: Allocate memory buffer
/k: To use Japanese file structures
/v: Data output to display
eg: \bin\mscdex.exe /d:mscd001 /m:8 /e /v
General Maintenance.As with all electrical equipment, ensure that liquid and metallic items do not get inside the machinery
Do not apply electrical shocks to it
If you are moving the interface card from one machine to another take care to ensure that you are not carrying a static charge
Try to ensure that the drive is not sited in a dusty environment
Do not move the drive or PC from a cold to a warm place suddenly as this may create condensation inside the machine. Wait for about 30 minutes before switching the system on.
Before moving the drive, make sure that you have removed the caddy if it uses one
Avoid placing the drive in direct sunlight or close to heat sources, and make sure that it will not be subject to vibrations.
Provide good heat dissipation, and do not cover the fan outlet.
What to do if things go wrong.Inevitably, things will, at times, go wrong with your system. However well you set it up, and however careful you are with it, something at some time will go wrong. This section covers some of the major points that you should take into account when this happens, and what you can do about it.
There are two rules that you should always remember.
First: Do not panic! There are very few occasion when quick action can save the day, and these are more than outweighed by the fact that you can create more problems for yourself by trying to act quickly without thinking.
Second: Back your system up regularly! If you do this, and do it on a regular basis, you won't need to panic.
Having calmed down and got a cup of coffee, try and isolate the problem. This may or may not be easy. First of all, ask yourself what has changed on your system. Have you for example added a new application? Moved the PC? Added a new piece of hardware? If you can, backtrack over what you did and start again, since it is possible that something may have been incorrectly added to your system. A good hint here is to keep a hard copy of both your autoexec.bat and config.sys files, as some programs will change them without telling you, and this may cause all sorts of problems, from not allowing another application to work through to not allowing the computer to boot properly. If you have kept a hard copy of both these files you can compare them to what is currently on the machine to see if there is any difference.
Make sure that you have a floppy system disk that you can boot the PC up on in case it refuses to boot.
CD-ROM problems.
The most common of these occur at the installations of MicroSoft extensions. There will be an automatic install program with extensions, and you should follow it. When you reboot, you should get two messages, the first saying that the device driver has been installed, and the second that extensions have been installed. You should always get the first message coming up, but there are a number of reasons why the second one may not. The most likely reason why you won't get this second message is that the line to call up extensions has been added at the end of the autoexec.bat file by the install program and might be placed after a line calling up a menu program, or a command to go into Windows for example. Consequently, this line is not being executed. Simply move it further up in the autoexec.bat file, preferably to become the first line, reboot and this time it should work.
Try doing a DIR of the CD-ROM drive. If you get the message CDR 101 Read Failed it normally means that there is a hardware problem. Check to make sure that the cables are all correct, that the CD-ROM drive is turned on, that a disc is in the drive and that it's the right way up. Open up the machine and check to ensure that the interface card is correctly inserted into an expansion slot.
Clean the disc! If you touch the read surface of the disc it will attract grease and dirt. If the disc is dirty, the laser in the drive may be unable to read the disc correctly. Clean the disc using a lint free cloth (so that you don't end up putting more fibres onto the disc) from the centre out to the edge, not around it. Check for scratches on the disc.
You may need to clean the CD-ROM player. This can be done by purchasing a cleaning disc and placing it in the drive. Do a DIR a couple of times, and that should have cleaned the laser head enough for you to continue to use the drive. This should only be a problem with older drives, as new ones have double doors and a cleaning mechanism built into them.
If the CD-ROM disc has been placed into the A: drive, if its a 5.25 drive. If the gate has not been closed, you may be able to tease the disc out using a pair of tweezers, but be careful here, since you do not want to damage the disc. If the gate has been closed, the disc is probably damaged beyond repair, and perhaps also the drive as well.
If you are unable to solve the problem for yourself, you should contact the technical support department of the appropriate CD-ROM publisher. Make sure that you have the following easily to hand:
10 If you have downloading problems, use a different floppy disk, and/or have details on the word processor package you are using, and which version.
11. If you have printing problems, what printer you are using.
Other points:
Are you the best person to contact Technical Support?
Have you checked the manual?
Are you near the computer?
Tell the support desk how computer literate you are.
If you've screwed something up, be honest and tell them.
Let them know that their suggestions worked!
Choosing a CD-ROM publisher.How long has the publisher been in existence?
How many titles do they produce?
What subject areas do they publish in?
What costs are involved?
What is their updating policy?
Replacement of faulty/damaged discs?
Technical support
How often is their software updated?
Do they have any promotional offers you can take advantage of?
Do they have local distributors?
Licensing issues
Try before you buy?
What platforms do they publish under?
How many versions of their retrieval software do they have?
What is their networking policy?
Do they offer training, or what guides etc. do they produce?
Online/CD-ROM versions?
Internet use - mounting databases across it, web sites, mailing lists etc.
Evaluating CD-ROM products.1. Acquisition issues
2. Cost
3. Software/hardware
4. Content
5. Interface
6. Company information.
1. Acquisition
2. Cost
3. Software/hardware
· DOS?
· Networking software requirements?
4. Content
Type of material (book, journal, newspaper articles), geographical scope, how many journals indexed?
Stop words, consistency (eg names)
5. Interface
6. Company Information
DVD Technology.What is DVD Technology?
DVD stands for Digital Versatile (or Video) Disc. It was originally developed for use in the video and motion picture industries.
DVD comes in a variety of formats - DVD-Video, DVD-Audio, DVD-ROM, DVD-R (recording).
DVD discs look the same as CD-ROM discs, but the difference is in the amount of data that they can contain:
|
Single layer, Single Side |
4.7Gbytes |
|
Dual layer, Single Side |
8.5Gbytes |
|
Single layer, Double Sides |
9.4Gbytes |
|
Dual layer, Double Sides |
17Gbytes |
On a single sided, single layered DVD it can store a full feature film with high resolution video, high quality audio and different language versions. Because seektime is so short it is possible to pre-programme different versions of the same film (eg X-rated or PG-rated). Quality of sound and picture will be high, lots of storage, low seektimes, seven speaker sound tracks etc. (133 minutes of full video and three audio channels) Data transfer rates will be higher than those of an 8x CD-ROM drive.
How is it used?
By using a DVD player, which will be able to play CD-ROM discs, although NOT CD-R discs. Data is stored in two layers, and the laser can 'see' through the first track and re-focus on the second one. Smaller pits, finer tracks and a shorter wavelength laser all go to improving the quality. The error correction is also going to be in the region of 10 times as effective as those in current CD-ROM Systems.
Dates?
The first DVD drives will be on the market in the middle of next year, and it has been estimated that by the year 2000 1.6 billion DVD and DVD ROM's will be sold annually.
It will initially be produced as a single sided disc with a single recordable layer.
Resources for more information.
http://www.tacmar.com/dvd_background,.htm
http://www.grimes.com/bnews/bnewsdvd.html
http://www.cd-rom-systems.co.uk/dvd/dvd.htm
CD-ROM - The future.Networking databases
Hard disk/pre-cache solutions
Common user interfaces
Improved hardware and software
Internet searching
DVD technology
Convergence
CD-ROM resources on the Internet.1. CDROMLAN
This is an electronic listserv dealing with all issues related to the usage of CD-ROM products in a LAN environment. All issues related to any CD-ROM product on any type of LAN are appropriate for discussion. Vendors of both CD-ROM products and LAN products are encouraged to participate.
To subscribe, send the following message to:
LISTSERV@IDBSU.IDBSU.EDU leaving the subject line blank
SUBSCRIBE CDROMLAN <firstname> <lastname>
Subscribers receive regular copies of the FAQ and a complete version of the FAQ for CDROMLAN is distributed to the list on the first working day of each month.
2. CDROM-L
Mailing list for the discussion of hardware and software issues related to the design, production and use of CD-ROM.
To subscribe:
LISTSERV@UCCVMA.UCOP.EDU leaving the subject line blank
SUBSCRIBE CDROM-L <firstname><lastname>
3. LIS-LINK
This is a general discussion list aimed at librarians and allows discussion on any topic whatsoever. There are sometimes discussions on various CD-ROM issues.
4. LIS-IIS
Similiar list to (3). Information on both lists can be obtained from:
5. Vendor homepages
Most CD-ROM publishers will have their own WWW pages on the Internet.
6. Newsgroups
alt.cd-rom
aus.cdrom
aus.computers.cdrom
comp.publish.cdrom.hardware
comp.publish.cdrom.multimedia
comp.publish.cdrom.software
comp.sys.ibm.pc.hardware.cd-rom