Features Research & Innovation
MAKING CDS

The CD, originally developed for music, has become the most popular way of distributing software, and most computers sold over the past three years have a disc drive that can read a CD.

CD readers are inexpensive, typically about $100 in a desktop computer and about double that for an external unit that can connect to a laptop.

It can be a major nuisance not to have access to a CD whenever new software has to be installed, since only the smallest and simplest software is sold on floppy discs. One relatively easy solution to operating without a CD drive in your computer is to be on a network where at least one computer has a CD drive.

Over the past year or so, disc drives which can also write on CDs have become widely available, at prices that are realistic for most users. CD writers (which can also read CDs) cost about $300 to $500, for desktop computers, and about 50% more for external units that can connect to a laptop.

The easiest CD writers to install are the Micro-Solutions devices that connect to a parallel port, but for higher speeds a USB port connector or card in an expansion slot in the computer is better.

Choose the fastest that suits the connectors available on your computer. Desktops normally have all three types of connector, but in the case of the very smallest laptops, the choice may be limited.

Installation is very easy. My son installed a CD writer without ever noticing that there was an instruction manual and a “quick install’ instruction sheet.

Some CD writer drives that use a PC card inserted in a laptop are advertised to operate on power drawn from the card. When inquiring about them we found too many limitations so bought the Hewlett Packard M820e. To install for a laptop, this unit requires an empty PC card slot, and has a separate 110-volt power supply so cannot be used when the computer is on battery power.

If you have a reasonably powerful desktop computer, with a Pentium chip running at over 200 MHz, there are a number of CD writers on the market. Normally, it is better to have an internal unit, if it is not desired to switch the drive from one machine to another frequently. If you have one CD writer on a network, everyone can use it, with some limitations.

For lesser computers, the parallel port CD writers are feasible, but performance may be disappointing.

Do not expect a CD writer with rewritable discs to be as convenient to use as your hard disc. One drawback is that it is necessary to choose between formatting the blank disc as a standard, ISO 9660 CD, or using the Universal Disc Format (UDF) format.

If the UDF is used, your computer will see a CD-RW as a gigantic floppy disc, with a standard drive letter, so you can read from it and write to it with virtually any software. However, the disc will be readable only in a computer that has Adaptec’s “Direct CD” or compatible software installed. This software is included with the HP CD writers, and either it or equivalent software with many CD-RW drives.

CDs written in the ISO 9660 format can be read by computers running under various operating systems such as DOS, Macintosh, OS/2, Windows, and UNIX, without any special software. Thus, it is a worldwide standard compatible with virtually any computer with a CD drive. However, it was originally designed for CDs produced in volume, which would be read by users, but not written to. This means that an ISO 9660 formatted CD will not look like a giant floppy. The ISO format is therefore most useful for distributing data or software, or for making archival backups.

Formatting a CD is quite like formatting a floppy disc, except that it requires up to about 90 minutes. It took about 30 minutes on our Toshiba laptop. You can use the computer for other work while the formatting is in progress.

One major advantage in the CD-RW technology is that you could have the hardware and software installed on two computers and keep all your data on the CD, so that taking work home would be easy. For those with security concerns, it is possible to work with up to 530 Mb data on a CD and simply remove it and lock it up when leaving the computer.

What kind of disc

to use?

For reading data or playing music, you use an ordinary CD in the CD writer drive. When making copies of files or CDs that virtually all computers can use, and you can accept the inability to re-use the disc space, the CD-R discs are best. They cost about $1.50 in the discount stores. The capacity of a CD is equal to approximately 500 floppies.

If you wish to be able to read, write and erase, as if the drive is a giant floppy disc, then CD-RW discs are necessary. However, they have the limitations mentioned above and cost up to about twice as much as a CD-R disc.

Is a CD writer

a good buy?

Only if you have a use for it. We have found the CD writer useful and easy to install. So far, it has been trouble free.

One major disadvantage is that if you also wish to be able to read DVD discs, then you will probably need two drives, which creates a space problem in some laptops.P&PC

CD terminology

“CD” is an abbreviation for “Compact Disc” but the full words are rarely used today. The original full name was “Compact Disc — Read Only Memory” hence the fast disappearing abbreviation CD-ROM. Of course it has always been possible to write on these discs, but the equipment required used to be far too expensive for anyone but major software developers.

The term “CD” is often used interchangeably to refer to the popular 120-mm diameter discs, and to the drive in the computer that can read, and perhaps write on the discs.

CR-R refers to a CD disc to which a user can record music or computer data with the kind of low-cost CD writer drives discussed in the body of this article. Once you have written on a CD-R disc, the space used can never be reused, just as areas of paper written upon with a ballpoint pen cannot reasonably be reused. Unused space can be used for other files. Although some software allows you to delete files from a CD-R disc, the space does not become available for other use. CD-R discs normally have capacity of 650 Mb data, which is equivalent to about 500 floppy discs.

CD-RW refers to a CD disc that is “Rewritable”, meaning that it can be written upon many times, rather like the familiar floppy disc. Capacity is normally about 530 Mb.

“Jewel-case” refers to the clear plastic boxes that CD discs are normally shipped in.