|ZX-81 Software Scene|
ONE of the factors against buying a ZX-81 is the time it takes to load a 16K program. The Fast Load Save routine from Musamy, for the 16K and up to 64K ZX-81, will speed the rate of saving and loading considerably.
The program will load at varying speeds, as some tape recorders cannot cope with the accuracy needed in conveying baud rates of up to 4,800 to the ZX-81. The baud rates available using the fast load routine vary from 2,400 to 4,800 on a scale of one to ten. That variable baud rate can be changed if you buy a more sensitive and more expensive tape recorder.
The routine will also give you a verify routine such as the one used on the Spectrum. That means that once you have SAVEd a program on tape you can verify the tape copy with the original before doing any NEWing. It means you can re-save the program without having to type it in again.
Also included on the tape is a tape loading aid. It acts as a companion to the Fast Load Save and will help you to test playback levels on your tape recorder. It will also test how 'noisy' the recording of your program is.
Fast Load Save is available from Musamy Software, London. It costs £6 for both the loading aid and the Fast Load or £3 for only the loading aid.
FOR MANY ZX-81 owners it would be a welcome relief to have a program to indicate exactly what was going wrong in a program just typed into the machine. Now all that is possible with Trace, a utility for the 16K ZX-81.
The program has been written in machine code so it will load above RAMTOP. You can then type-in your Basic program as usual and run it for any errors which may occur.
If the program stops with an error code you can use Trace to look at the structure of the lines running up to where the program crashed.
To trace through a program you have to call the utility using either a direct machine code invoke command or using a call in a program.
Invoking the utility in a program has the advantage that you can trace through a few lines which occur in the middle of some code.
When Trace is invoked you should see the number of the line which is being executed displayed at the bottom of the screen and the effects of the program line on the rest of the screen.
In that way you will gain a better understanding of what each line is doing and how it fits into the structure of the rest of the program.
Trace is an excellent utility which provides a useful addition to any ZX-81 owner's programming library. You should find it helpful in dealing with bugs in any Basic program.
Trace can be obtained from Texgate Computers Ltd, Dorset. It costs £5.95.
WORD PROCESSING is very difficult on the ZX-81 but that has not prevented Contrast introducing Text, a word processor for the 16K machine.
It is written in 100 percent machine code and, as a result, works extremely fast. It is unfortunate that it does not make the computer adequate for word processing. The keyboard still remains almost impossible to use as you cannot tell whether a key press has been successful.
If you are willing to tolerate those inherent difficulties, you should find Text to your liking. The program includes all the usual text-editing facilities, including justification on the left and right, block move, search and replace text, and delete.
It will enable the user to store up to 350 lines of text - approximately 11,000 characters using the limited ZX-81 upper-case lettering.
The program has a help option and everything is included to make the reader at home with the program. It is unfortunate that the software is confined by the hardware.
Text is available from Contrast, Hampshire. It costs £5.95.
THERE ARE few companies still selling 1K ZX-81 games and Selec Software is one of them.
The programs may not be anything special but the way in which they are fitted into the 1K memory space must be praised.
Two of the best cassettes in the range include 1K The Invaders and 1K ZX Panic/ZX Squash. All the games on both cassettes are in machine code and their speed is the main attraction.
The Invaders is a typical game of space invaders. You have to hide beneath your three laser bases and, when you can, get as many laser shots as possible at the enemy invaders.
The control keys are a little awkward to handle but once you are used to them there should be no difficulty about enjoying the game to the full.
Panic is a target-shoot game in which you have, yet again, to bag as many aliens as you can. The game can become a little tedious after about half an hour of continuous play but if you want to play something else you can change to side two of the cassette and play ZX Squash.
That involves two players who must take turns to hit a ball against a wall.
If you do not like the idea you could always imagine that it is a two-player version of Breakout.
Both tapes can be obtained, for £3.50 each, from Selec Software, Cheshire.
|Spectrum Software Scene|
ADVENTURE games have always proved a popular part of the Sinclair software market but until now it has proved almost impossible for a user who knows little about computer programming to write one.
That has changed with the introduction of The Quill, an adventure game utility for the 48K Spectrum. The program will allow you to design an adventure game, complete with dungeons, monsters, items and treasures. It will then compile all the information into a machine code file. That means the game you obtain finally from the program will be in machine code. If that is not good enough the machine code game can then be loaded independently of The Quill program.
Each adventure can be different from the last and they can be made as easy or as difficult as your imagination will allow. With the utilities available in the package you can create a dictionary of words specific to your needs. Of necessity they will usually be a verb followed by a noun.
The package is backed-up with a well-structured manual which starts with the simple concepts of creating an adventure with The Quill. It then goes into detail about how the package is structured.
The author does not seem to be concerned how much the user knows about the package. As a final note the manufacturer does not mind if adventures created using The Quill are sold commercially by their creators. It would, however, like to be mentioned on the cassette inserts and the program.
The Quill opens a wide area of activity to people who have always wanted to write adventure games. Now all you have to do is provide the story lines to make them interesting. It can be obtained from Gilsoft, South Glamorgan and is inexpensive at £4.95.
PIT YOUR WITS against an emissary from the past. This is no space invader but an automaton called the Turk who will give you a good game of chess.
Chess - The Turk is for the 48K Spectrum and contains many options which are unusual in chess games for the computer. Before you play you can see how good the Turk is by watching the program play against itself. Levels of play range from one to six and will take a few seconds on level one to six hours on level six.
If you are an average good player for your age you may care to try level two, or perhaps three at most, as they will give you at least some chance of winning.
If you have been adept at the game for some time you might like to take on the program at Blitz Chess. The name is apt as our board looked like a map of London after the war in just 20 minutes of torment. The reason is that Blitz Chess is against the clock.
The game will allow all legal moves, including en passant and pawn promotion. It also allows you to switch sides during the game or, if you want to cheat even more, remove the Turk's queen from the board.
Chess - the Turk is well packaged. It can be obtained from Oxford Computer Publishing, Oxford. It costs £9.95.
XATRO is a cunning devil. He left seven parchments on Invincible Island, ready to be found by an aspiring adventurer. To find the scrolls you have to climb mountains, enter a walled area which looks like China and descend to the bowels of the earth.
Those locations, and many others, are displayed with colour graphics on the top half of the screen while the instructions which you give the computer - the descriptions of items found along the way - are displayed as text at the bottom.
The initial stages are easy and give no indication how difficult it becomes when you hit the wall of 'China' or find your first scroll. Our inclination, after wandering around for some time without much hope or help, was to concede but suddenly events took a drastic change for the better - we found our second scroll.
The infuriating thing about Invincible Island is that just as you are ready to commit suicide and pull out the plug in desperation the problem facing you resolves itself and the adventure takes an upward turn.
Invincible Island graphics and storyline should keep everyone happy for several hours. It costs £6.50 and is available from Richard Shepherd Software, Berkshire.
THE DEPTHS of your mind and personality will be probed with Star Gazer, an astrological program for the 48K Spectrum. All it requires is your birth-date and time, together with the longitude and latitude of birth. It will then provide a horoscope designed with your natal data in mind.
The computer will ponder the data for about two minutes and then draw a chart with all the planets in the relevant signs of the Zodiac and the houses, calculated using the Equal House system, around the circular rim of the chart. It will then give you a character reading depending on which planet is in which house of the solar system. Each house is taken in turn and by the end of the reading you should know things about yourself which you did not know previously.
Several readings were done in the Sinclair User office and when compared they seemed to be very similar. The readings were general in description of personality types, so that everyone found something in them which was true.
If you are a novice at astrology and want to learn more, the program will give you the opportunity at the end of the personality profile. If you select the option for more information it will tell you how to interpret the chart and where to obtain more details about the subject.
The package is very comprehensive and was written by a member of the Astrological Association. If you want to know more about the occult side of your nature, it draws a good horoscope.
Star Gazer can be obtained from Computer Rentals, London. It costs £5.95.
MUTANT telephones, killer penguins and caverns of ice are all part of Manic Miner for the 48K Spectrum. The game includes some impressive graphics routines which you will encounter when you take your player-character, Willy the miner, through a series of caverns inhabited by all kinds of strange creatures.
To exit from a cavern you have to pick up a series of keys hung from various parts of the ceiling or from bushes which are deadly if you touch them. To reach those keys you must jump on to ledges which are situated at various heights and you must jump in the correct order or you will fall back to earth again.
If you are not careful you could bump into a patrol robot, shaped in various guises, which will take away one of your lives.
The other killer is a fall from one of the ledges which disappears as you walk along it. If the ledge is high a life could be lost.
The game is very inventive and a great deal of thought must have gone into creating the many screens full of colourful characters. It is one of the few games on the market which deserves to succeed automatically because of the effort put into it. It has the depth of concept and quality of sound and vision to make it an instant winner.
If you cannot pass all the caverns and discover the secret of the game in the last sector the author has included an excellent taster routine which runs automatically at the start of the program. It shows the various caverns as they can be seen in the game.
Manic Miner should keep anyone, child or adult, enthralled through the long winter evenings. It costs £5.95 and can be obtained from computer branches of W H Smith.
THE ARENA is filled with hostile robots as you, the last of a race of fighting robots, battle for your life. In Spectron, for the 48K Spectrum, your laser gun is on automatic and will fire as you move. With luck - and just a hint of skill - you should be able to destroy the enemy and prepare for the next battle.
The game sounds simple so far but in playing you have to take account of a number of factors which will affect your health, such as energy. You also have to tolerate a potential score which seems to get higher and higher.
Virgin Games, the manufacturer, has some accurate figures on the statistics of the game. You can have up to 54 robots and missiles on the screen at once, which is not good news for the lone survivor of a race of tin cans. It is, however, surprisingly easy to pass the first levels without too much trouble but after that the evil robots could gain the upper hand, or claw.
If you play the game for long enough you will become addicted. It is simple but you will always want to reach one level higher every time.
Spectron is produced by Virgin Games and can be obtained from Boots, Menzies and Dixons. It costs £5.95.
THE CIRCULAR corridors of the computer installation based on Genon hide a dark and deadly secret. They are inhabited by a creature called Bogul. The creature and its cloned counterparts will try their best to stop you reaching the main computer, cracking the secret code and returning to the outside world before the base explodes.
Corridors of Genon, for the 48K Spectrum, is in a long line of 3D games from Malcolm Evans and New Generation. It is set in the usual maze but the unusual thing is that the corridors are circular. That effect works well and is added to by the sliding doors which lower from the ceiling to block your way. Depending on the level at which you are playing you will be given either the pass number of the door to make it open or you will not.
The most difficult part of the maze is the centre, at corridor 30, where doors are closing all the time, pass codes are hidden, and you can hear Bogul's footsteps getting nearer.
When finally you beat corridor 30 you will be introduced to the computer. In that room you have to guess the destruct sequence code of the computer. That is such an important part of the process that when the program is first loaded, and before a new game begins, you will be asked if you want decoding practice.
Once you have cleared the code the computer will tell you that all is well but that Bogul has multiplied and there are then several of the trumpet-nosed creatures wandering the maze. Before the game ends you must pass all of them and get out of the maze.
Corridors of Genon is an excellent 3D game from a master of 3D techniques. We cannot recommend it too highly. It costs £5.95 and can be obtained from New Generation, Bath.
ARCADE GAMES on the 48K Spectrum are still all the rage but it is difficult to find one to better the original. That is the case with Invasion of the Body Snatchas from Crystal Computing.
The name of the game may be different but the concept is still that of Defender. You must pilot your spaceship left and right over the alien landscape, shooting-down aliens, avoiding mutants if possible, and rescue refugees from certain death.
Sex equality has finally reached the Spectrum as the refugees are women as opposed to the men of the original. That is not the kind of equality most people have in mind, though, as the women are dropped from staggering heights.
The screen display is effective and, if you were to put the computer under the table, you would not know the game was running on such a small machine.
This time Crystal has added sound and it is very effective. You can, however, access the buzzing and zapping noises only through a Fuller sound box. That is not a deficiency in the program as, with the type of sound being created, you would not be able to gain a true appreciation through the tiny Spectrum speaker.
If you are sufficiently clever and quick-witted you will gain entry into the Hall of Fame. The high-score table is sure to gain notoriety as the program will trap certain names and phrases typed into it and output messages from Crystal Computing. It was distracting trying to find the names which put up the messages, though it was nearly as enthralling as playing the game.
Invasion of the Body Snatchas is an essential buy for all arcade fans. It can be obtained from Crystal Computing, Sunderland.
MOST YOUNG 48K Spectrum owners dream of being able to write a prize-winning machine-code arcade game. The dream can be a reality with Games Designer for the 48K Spectrum from Quicksilva Software Studios.
The package will enable you to build various game elements into the game of your choice. You can design large animated characters, called sprites, and make them into spaceships, witches, demons, or even mutant hamburgers.
Once you have designed the characters you can decide their movements with the attack wave designer. With the aid of this tool you can make the game as difficult or as easy as necessary. Explosions, zaps and even space-ship engines can be manufactured using the sound generator. It can be programmed to take effect when an alien or laser base is hit.
To manipulate games you need no programming experience. The disadvantage is that the games you create will not run independently of the Designer program. You have to load the main program and select the game load option to play back the program you have created.
Although you can create a variety of games, with aliens appearing from the sides, top and bottom of the screen, the types of game will seem finally to be all the same. In effect all you are doing is zapping aliens and there is no change to the format.
To become used to the package you might like to try one of the eight games included on the new game menu.
They include Attack of the Mutant Hamburgers, Hallowe'en and Reflectatron. Most of them will provide a certain amount of fun but many of them just emphasise the point that they are the same games but with different aliens, moving in different attack waves.
If you want to program games with no programming knowledge, Games Designer is for you.
It can be obtained from Quicksilva Ltd, Hampshire. It costs £14.95.
ORACLE'S CAVE, for the 48K Spectrum, hints at the way in which adventure games might develop in the near future. It is a graphics adventure but like nothing which you have seen previously. The screen is split into two parts and the scene is set in a matrix of caverns. The caves and your player-character are shown in silhouette and when you want to move around, the cave system will scroll in the direction of movement and the player will walk or climb.
The screen display, also includes a chart showing the level of your energy and combat strength, together with the weapons, items and treasures you have found. Each quest is selected by you at the beginning of the game and you will have five game days in which to complete it. The time factor is exceptional in adventure games.
Oracle's Cave breaks away from the traditional concept of adventure gaming. It provides moving graphics displays which enable you to imagine the situation in which you are playing as if it were real.
One criticism, however, is that the command words are shown throughout the game. Unlike other adventures they are not hidden for the player to find. If you want to find a keyword you will often have to refer to the textual instruction on the cassette insert. For instance, k stands for key and r for rope. Memory restrictions may have interfered with putting more into the program but it would have been better to include explanations of words on the screen.
Oracle's Cave can be obtained from Doric Computer Services, Leicester.
MELBOURNE DRAW program for the 48K Spectrum gives you a utility which permits the sketching of pictures on the screen using a cursor. The pictures can be saved, loaded and manipulated using this design aid.
The program will also enable you to create graphics and characters in your own programs.
When first loaded the ease of use of the package is not apparent. You are faced with a long menu and, when you select the edit picture mode, you will be faced with a black papered screen and some status words below.
Before you can start drawing you must clear the screen paper so that it is white. Then, according to the 20-page manual with the cassette, you should see a cursor near the middle of the screen. The manual fails to inform you, however, that the cursor is only one pixel wide and if you wear spectacles you may take some time to hunt for it.
Once you have drawn a picture you will be able to manipulate the result.
You can change attributes, flash various parts of the screen, invert parts of your picture, and scroll parts. Once you have finished you can save the result on to tape.
The impression we gained from looking at the booklet and the material written on the back of the display box was that the fantastic graphics, which you can create, if you are clever enough, can be used in your own programs. That produces visions of little animated figures which make up the main part of your games.
The only real benefit we could find was to put SCREENs at the beginning of the games. That could be done just as easily by writing a program to draw a design and then SAVE it directly. Admittedly the magnification, scroll, flash and attribute options are useful but if you are designing a screen you can do without them.
Melbourne Draw may be of interest to artists or professional software houses who want quick graphics results. It can be obtained from Melbourne House, London. It costs £8.95, which is expensive for such a utility.
MOST GAMES for the 48K Spectrum boast that they will show you the answer to all your prayers, the answer to the ultimate question, and Pyramid is no different.
The difference is that during the game you must play a cosmonaut who is seeking the real answer to the ultimate question of life, the universe and everything, which was formerly thought to be 42.
To do this you have been zapped into a pyramid of many levels and chambers. As you gain entry to each chamber you are one step closer to knowing the answer. All that stands in your way is the many creatures and objects which inhabit the dark corner of the pyramid.
You must clear each chamber before you pass to the next and the speed at which you do so will make points. The more points and experience you amass the bigger your code will become.
The code is the manufacturer's way of checking how far you have advanced in the game. If you send it to Fantasy Software you could be entered into its Hall of Fame. The code is displayed on the screen.
The scope of the game will ensure that you will be playing it for months, if not years. There are 120 chambers on 15 levels and there are 60 types of aliens in those chambers. Most of the beasts defy description.
Pyramid costs £5.50 and can be obtained from Fantasy Software, Glos.