Atari was born when Nolan Bushnell created Pong, the first arcade game.

After a shaky start, the company was bought by the massive Warner Brothers and, about eight years ago, the first Atari games console was released.

It was the first 'programmable' video game console and quickly became the best-selling game in the world. It is for this reason that Atari became known as a games company and the release of the 400/800 computer range in America about four years ago was supposed to launch Atari into the serious computer market.

Although the computers were top sellers in America, Atari's games image hindered the sales of its micros in this country when the 400/800 range was released here about three years ago.

The Atari 400 was originally supplied without the Basic language which probably furthered its games image.

In order to keep up with a fast-moving market. Atari had to continually cut its prices to match new computers being released with similar facilities. After three years, the Atari 800 has now dropped to £199 including Basic and 48K, a drop of £630 at the old prices.

Unfortunately for Atari, while the prices of its computers had to fall, the cost of production would not drop at the same rate. The computers were manufactured on at least six circuit boards.

The luxury design of the 400/800 range caused Atari price war headaches, and is the major reason why Atari brought out its new computer range with a futuristic and stylish image and a design with all of the components on a single circuit board.

Atari now dispensed with the much criticised membrane keyboard, fixed a few bugs in the operating system and the Basic, and revamped the Atari 400 into the Atari 600XL, with many additional features. And the 800 has now been replaced by the 800XL (a 600XL with 64K of RAM built in).

Many people looking for a computer now seem to be interested mainly in the expandability of their potential purchase. The fact that Atari has recognised this is shown in the design of the new machines. The 600XL is upgradeable to 64K RAM. An expansion port (not built onto the 400/800 range), is also included for such goodies as a CP/M operating system, 80-column expansion etc.

The first in the Atari computer range, the 400 was originally releaed with the then maximum 8K of RAM. Now upgradeable to 48K the only real criticism levelled against this machine is its membrane keyboard.

The 400, like the 800, has four joystick ports along the front. There are not many programs that can use this many ports but, using paddle controllers, it meant that up to eight people could play a game simultaneously.

The 400 and the 800 both have 10K of ROM and an 8K Basic ROM cartridge is also included.

Atari solved some of the problems of a membrane keyboard using simple things like raising the edges of all of the keys and using a built-in speaker that would bleep every time a key is pressed, and a number of full stroke keyboards are now available for £40.

The keyboard itself is of the standard qwerty type and four 'function' keys are included down the right hand side. The first of these, the SYSTEM RESET key, is an 'if all else fails' alternative, resetting the entire system and returning certain locations to their standard (default) values. The next three, usually used in games, are OPTION, SELECT and START and can be read individually or in different combinations.

The 400 has a cartridge port in the top of the machine, covered by a spring-loaded door that turns off the computer when opened to protect circuits while cartridges are being inserted and removed. To the right of the machine is the power switch and an Atari serial interface for connection to Atari printers, interfaces, disk drives, program recorders, etc. A non-detachable RF cable comes out of the back of the machine for connection to a standard television set.

Second in the Atari range of computers, the 800 is the more professional of the originally released models. Still with 10K of ROM, the 800 is more expandable by means of a lift-off top that allows you to add memory boards easily (although the last 800's were supplied with the full 48K). Other American companies have also released add-on boards including an 80-column board, a CP/M board, and one which will add 64K of RAM to the existing memory.

The 800 has two cartridge slots and is the only Atari computer to have them both. The second port was designed at a time when the largest amount of memory that would fit on a cartridge was 8K and the second slot was supposed to take an additional cartridge to provide 16K extra ROM.

In fact, the only cartridge currently available that can use this slot is one called Monkey Wrench. This program is an expansion of Atari's Basic adding extra commands, etc.

The power switch, RF cable and serial port are the same as the 400 but there is also an output for colour monitor. This monitor should be of the composite video type and not RGB.

As with the 400, the power supply is also a separate unit and there are four joystick ports on the front of the machine. These ports can be, and have been, used for output as well as reading joysticks. Hardware such as printer interfaces have already been developed using these ports.

The only 'odd' key on the 400 and 800 computers is the Atari symbol. Pressing this key reverses the text to give blue text on a white background. This key has been replaced on the XL range by the less confusing symbol of a square half white and half black.

The first of the new generation of Atari home computers, the 600XL is the lower priced of the models currently available. The 600XL was released just before Christmas giving a more professional alternative to the Atari 400 at a similar price.

Unlike the 400/800 range, the 600XL has the Basic language built into the computer and the cartridge door has been replaced by a hatch with spring-loaded dust covers.

The two joystick ports are located on the left of the computer. The power switch is on the back of the computer along with a socket to connect it to a composite video monitor.

The power supply for the XL range is larger than the old style one, it is quiet and is much less likely to suffer from overheating.

The Atari serial port is still included although it is on the back of the 600XL. In addition there is a special expansion bus that will allow the addition of extra cards such as 64K, 80 columns and so on.

The 600XL is supplied with 16K of RAM as standard, and can be upgraded to 64K. The machine also has a total of 24K of ROM in the form of a 16K operating system and the 8K Basic. The larger ROM in the new machines supports extra Graphics/Text modes in Basic.

Software that used the old operating system bugs to take short cuts will not work on the new machines. The number of programs discovered that do not work is about 10 per cent.

The 800XL is identical in all respects to the 600XL except that the machine is supplied with the full complement of 64K RAM built in. This makes the case a little longer and tidier than that of the 600XL. The prices of the 800XL and that of the 600XL with the 64K expansion are almost the same. Obviously the 600XL allows you to start using an Atari machine at a comparatively low price. After using the 16K machine for a while you may decide that 64K is not necessary and you would have saved yourself almost £90.