Kempston Joystick & Interface

Big K

John Conquest

STICKS MAY BREAK... ...Or do their bearings in, but nothing fazes John Conquest. He's got plenty more to fall back on. Look through the computer mag ads and you'll see that there are a lot of people trying to sell you custom joysticks, all convinced that theirs is the real McCoy. "Arcade action", "instant response", "high quality", "professional" - writing joysticks ads looks like a doddle, but what we're concerned with here is the rather more difficult business of actually buying one. Obviously the first consideration is compatibility, whether or not the widget will fit your machine. Virtually all the joysticks currently available are designed to fit Atari video & computer systems and Commodores, though they'll also work on CBS's Colecovision videos (you'll still need a standard controller in the second port to make the games run). Wico supply adaptor leads for Apple and Radio Shack marchines and, like Suncom, for Texas instruments TI 99/4As. A rare exception is Suncom's Strike Commander (£18.95), made specifically for the BBC or Dragon, though Kempston are also planning a BBC stick. VEXED The vexed question of interfaces is one on which you'll need expert, and hopefully disinterested, advice. For Spectrums, the Kempston at £11.50, which will accept any stick, has only one drawback, a single port. For BBc's the Wizard at £14.95 is recommended. The basic rules are not to get joysticks with plugs jury-rigged to fit machines they weren't designed for (they don't work too well) and to avoid anything that needs a program to make it run. A less obvious but vital consideration is the size of your hand. Believe me, that's important. Many of the sticks I tried simply weren't comfortable, but might well suit someone with smaller, or indeed larger, hands and this applies especially to shaped grips. Unfortunately a lot of shops stock a very limited range, usually Quickshot IIs or Point Masters, so for this and many other reasons it's well worth while going to one of the big computer shops and trying your hand at their range. Lion House in London's Tottenham Court Road, for instance, has 17 models ready to be hooked up for demonstration, and the Silica shop in Sidcup reckons to have at least 15 of a possible 26 in stock at any given time. Even if you just try them for feel, you'll notice the differences. Ask yourself realistically how much you're going to use a stick. Price differences are almost entirely down to quality of construction and the cheap ones simply aren't up to a lot of punishment. If you're heavily into 'Decathalon', to take an extreme example, a cheap joystick is going to be a waste of money. With joysticks you get what you pay for with a vengeance, and Atari owners at least should calculate whet her they're really improving on the standard issue sticks. OBVIOUS The most obvious differences between cheap and not so cheap sticks are whether or not they have steel shafts, the grade of plastics (high impact or extruded) used and the general solidity of construction. What you don't see is the guts, which is what really sorts them out. Very few sticks have microswitches (though Kempston are rumoured to be using them in all future models), but the leaf switches found in most vary considerably in quality and the cheap ones have very limited lives. Also hidden inside the casing is the shaft mounting which is another thing that decides whether or not the stick will go on doing what you want it to do. You should also think about the kind of game you usually play. Sticks come in two basic configurations, with the fire button in the handle, either centre fire on the top or trigger fire in the handle itself, or mounted on the base. I'm convinced that handle fire is a major contribution to fire control. Most of the sticks with handle fire have a base button as well, which can be a nuisance when hand holding, and some base mountings are available in either left or right hand versions or already have both, either as separate buttons or as a bar across the width of the base. Most of the sticks mentioned were tested with Activision's Atari computer version of River Raid.It requires precise manoeuvre, reliable and responsive speed control and pinpoint fire - in other words it uses everything that a joystick ought to offer. The cheapest sticks around are Acorn at £13 a pair (soon to go up to £19), which are so terrible that nobody seems to stock them. The Pinnacle at £7.95 is admired more for its price than for the quality of its 8-way movement and handle and base fire buttons, but if you really want to spend the minimum, this is the one. For £9.95 you can get Spectravision's Quickshot I with centre handle fire and sucker feet, which, for rather more, is a standard Spectrum interface offering. Like its big brother (below) its shaped handle makes hand size critical. Easy to use, though because of the shaft mounting rather loose, it's as fragile as it looks and would last about five minutes in an arcade. Its leaf switches have a poor reputation. Alternatively there's Suncom's Slik Stik, the cheapest half way reasonable stick, which has a ball grip, a left hand side base fire button and is a nice hand size. Solidly made, it's the kind of thing Atari ought to be offering as standard. First in over the £10 mark is the very basic Kempston 1000 (£10.99) which has little over the Slik Stik except a base fire bar, workable from left or right. The handle suggests that it might best be controlled with the thumb. It's followed at £11.95 by the Quickshot II which is identical to the junior version already dealt with except that it has 'auto rapid fire' via a trigger in the handle, its main selling point. LOOSE FEEL The Triga Command (£12.99) has a very similar loose feel, again due to the shaft mounting, and looks very plasticky. It has a trigger tire only (and suctions cup feet) and comes in £19.99 versions for Spectrum and BBC. The handles design however is excellent with a diamond cross-cut pistol grip that is very satisfying. The much solider Kempston 3000 with handle centre, trigger and base fire bar buttons is El 2.75. At £12.95 you can choose between the Point Master, very similar to the Quickshot II but slightly less robust, and Sumlock's all-British Pro-Ace which resembles the Kempstons in its solid high-impact plastic construction and fire bar (plus centre fire in the handle), but which I found sluggish and awkwardly shaped. On the other hand, Sumlock back up the quality of their leaf switches with a two year warranty, so it should be pretty reliable in the long term. The top of the range Kempston 5000 (£13.50) is, again, a very solid piece of work with a ball grip on a short, tapered steel shaft and both left and right hand base fire buttons. It feels a bit stiff but I'm told that it wears in well. The next Suncom, the £13.95 Starfighter (also available in a ritzier version for Apple computers at a very ritzy £39.96) is a very nice hand size with excellent manoeuvre and speed control. It has a left hand base fire button and a stubby unshaped plastic handle that I found far too short, but that's me. Wico, like Suncom and American firm, make their first entry at £14.95 with The Boss, a muscular brute that I found very heavy to use, aggravating my advanced case of video wrist, but very positive. However as the hand grip is shaped for a much smaller hand than mine, it's virtually unusable in my glove size. The Arcade at £15.95 is the cheapest stick that one can get really enthusiastic about. Dutch made, with very superior microswitches, it's extremely positive and responsive, a real pleasure to use. This is an excellent device and highly recommended - not just by me but by Lion House where it's a big favourite. STEEL SHAFT Back to Suncom at £18,95 with the TAC which has a ball handle, steel shaft, nonslip feet and left and right hand side base fire buttons. A nice size for hand holding but, despite the amazing manoeuvre control, I find the shaft too short, the fire buttons need very firm instruction and the game (River Raid) seemed much speedier than with other sticks. The legendary Le Stick at £19.95 boasts unique mercury switches, but they're a mixed blessing. While it's ideal for one-handed use and suits games like Decathalon superbly, firing jogs the switches so that it has a tendency to jump about when you start shooting. Le Stick is if anything too responsive and so hard to control, making it a real wrist killer. QUALITY Jumping to £24.95 we have another Wico, the Red Ball a quality number with a longer steel shaft, a good size ball handle with built in fire button, plus another on the base, and all the control one expects from Wico widgets. However at this price I'd spring another £3 to get the £27.95 Wico Three Way. This is my personal favourite of all the sticks I tried and, for my money, the top of the range. It has a very long steel shaft, which means a far better 'throw', and three different clip-on handles, though in practice I only use one, the slim tapered job. The Three Way has a centre fire button in the handle and another on the base, but it offers a unique switching feature which enables one to cut off the base button, extremely useful if, like me, you like holding the stick in one hand and working it with the other. With other dual fire sticks it's very easy to find your fingers working both fire buttons, which may not be what you want. For River Raid at any rate the Three Way is the primp stick for control, fire accuracy, delicacy of manoeuvre, speed control and overall feel and response. TOUGH BABY From the same stable as The Arcade comes the Professional Mark at £28.95, which looks rather like it had been ripped off the front of an arcade machine. This is one tough baby and though I can't help wondering exactly what 'Professional' means in this context, if anything deserves the name this does. I imagine some of you must at some time have put your noses into a video arcade. If so, you'll know exactly what to expect from this one, The joker in the joystick pack is Suncom's Joy Sensor which looks rather like an upmarket version of Intellivision's control pad. I can't make it work and though I've heard rumours of people who have mastered it and love it. I've never actually met one of them. All it gives me is vicious oversteer. At £29.95 this seems like a real gamble, but maybe I'm missing something. MOVE BLIP All joysticks do pretty much the same thing, move a little blip round a TV screen. So how come there's a £20+ difference between the cheapest and the most expensive? Well, it depends on whether they're being made to a price or to a standard. I am not a racist... but. The tell-tale on the cheap sticks is the 'Made in Taiwan, Hong Kong, South Korea' and there's no getting away from the fact that they're not in the same class as the American and Dutch made sticks. The trick is to find one that suits both your hand and your pocket, which is why you need access to a wide range. However even the big shops have no consensus view; Lion House are big Wico fans, plugging the price range with the Pinnacle and The Arcade, while Silica Shop prefer the Suncom Slik Stik and Starfighter with the Quickshot as back up. To me the ideal stick would be a cross between the Triga (handle design), The Arcade (micro switches) and Wico Three Way (everything else), in the real world three sticks seem to me to stand out as value for money and they are: 1. Suncom Slik Stik - £9.95 2. The Arcade - £15.95. 3. Wico Three Way - £27.95

ABOVE: the Spectravision 2.

Both Spectras.

LEFT: Suncom Slik Stik. RIGHT: the Joy-Sensor vicious oversteer.

The Professional.

The WICO range - with the 3-Way top of the list.

The lot.

Your Computer

Tim Langdell

Although nowhere near as profuse as Spectrum software, various add-ons have now appeared to bridge the gaps in the micro's specification. Tim Langdell reviews. It is almost a truism to say the Spectrum has been pushed to its limits. A great deal of time has been devoted by software houses to creating programs that put more sophisticated machines with less well-thought-out software to shame. Nevertheless, there is scope for peripherals which even up some of the Spectrum's primary hardware inadequacies. UNDER CONTROL Following up its success with a controller - that is, a device which allows you to switch between Loading and Saving, disconnecting the computer when saving and vice versa - Abacus has introduced one for the Spectrum. This means more reliable Saving and Loading. Unlike the ZX-81 version, the Spectrum controller also includes an amplifier, a particularly useful feature in view of the Spectrum's own weakness in amplification. Setting up the controller simply requires plugging the Spectrum's power supply into the side of the Abacus box and the power lead from the box into the back of the Spectrum. The Mic and Amp leads are used to connect the Spectrum to the tape recorder. Kempston's joystick is a standard design with fire button and control stick working on a switching rather than analogue base. This means that it can be used to simulate the detection of keypresses. The joystick is mapped to Port 31 of the Spectrum, and can be accessed with the IN command. The value returned by detecting Port 31 in this manner can be between 0 and 26 with the eight directions from forward through NE to E, SE, S and so on being values 1 to 10 - omitting 3 and 7 - and the fire button returning 16. The joystick can be read in machine code too for a faster response and arcade-like action. The joystick's connector is a small black plastic box with two matt-black TTL chips visible on the outside which plugs straight in to the Spectrum's printed-circuit board. The joystick itself is very responsive. My only quibble is that a spring-back-to-centre mechanism would make the central off position easier to reach when playing fast arcade games. The joystick costs £19.50. This company has also brought out one of the first 24-line I/O ports for the Spectrum. Simply constructed - a single TTL chip supports the operation of the 8255 PPI chip - the board comes with clear documentation which indicates how one can use the three 16-pin dual in-line sockets or a 24-way edge-connector attached to the back of the printed circuit board. The 8255 chip has several modes of operation: the three I/O ports can be configured in the following ways - setting up one bank as inputs, another as outputs, with the option of "handshaking" on port C. Using the In and Out commands the port can be accessed from both Basic and machine code. Apart from the back-to-back edge connector the port can be limited to the Spectrum with a stackable edge-connector, or a motherboard. The stackable edge-connector allows an extra device to be attached to the Micro whilst the PPI is attached. The motherboard will take two cards in edge-connector sockets as well as a Printer or a Microdrive. The motherboard is supplied with its own 5V regulator. The 24-line PPI has been configured in the Spectrum's I/O map so that it will not clash with the Printer Microdrive or RS-232 interface. The PPI costs £16.50, the stackable connector is £5.50, and the two-slot motherboard is £16.95. ADD ZX-81 HARDWARE There are three Adam adaptors for the Spectrum; each allows you to add ZX-81 hardware on to your machine. The fundamental adaptor provides a ZX-81-compatible output port at the rear of the Spectrum, but no address conversions. The adaptor comes with a computer printout description which tells you how to attach memory-mapped devices which do not decode the lower five address lines in the I/O map. The next adaptor - the Adam II adaptor - allows the simultaneous use of two sets of peripherals on the rear of a 16K Spectrum. This adaptor allows you to attach a ZX-81 16K RAMpack to a 16K Spectrum. The Adam II adaptor can interface with any ZX-81 peripheral which was designed to work in the 0 to 16K region of the ZX-81's memory map, by using it in the 48K to 64K region of the Spectrum's map. Thus ZX-81 equipment will require 49152 to be added to its addressing, and for this reason EPROMs designed to work on the ZX-81 will probably not work on the Spectrum. Finally, there is the more adventurous Eve adaptor, for those with a 48K Spectrum. With a 48K Spectrum all 64K of the address lines on the Z-80A CPU are already accounted for - 16K ROM and 48K RAM - hence adding any device mapped in the RAM area seems impossible; especially as Sinclair did not provide a RAMCS line at the rear which would have allowed us to turn off some, or all, of the internal RAM. By adding this adaptor and making a few soldering connections inside your Spectrum you can turn off 8K of the upper 32K of RAM and map devices into this area. Of course, making the alteration could invalidate your guarantee. The RZ-1 Tape Controller is another more recent device from Stephen Adams. It provides both Spectrum and ZX-81 owners with a programmable tape control unit for stopping and starting the cassette motor under software control, or disconnecting the load lead when Saving and vice versa. The RZ-1 plugs in via an edge-connector. The rear connector of the machine is duplicated behind the RZ-1, so a peripheral unit can still be attached. The RZ-1 can control two tape recorders and provide a minimum of five latched outputs for controlling external devices. Furthermore, it does not use any memory locations, either in RAM or in the I/O map. The unit is located in ROM space between 512 and 1024. Poking various locations in this region allows you to turn on any of the tape motors, or to provide an output to one of the ports. UPGRADE RANGE East London Robotics provides a range of RAM upgrades for the Spectrum: the SP-48A which adds a further 32K of RAM to the 16K Spectrum Series 1 on a plug-in board; the SP48 for the current Series 2 version of the Spectrum and an SP-80 RAM add-on which gives not only 32K of extra memory but another 32K which can be accessed as well, using Out commands. It is thus possible to use a full 80K of user RAM with this board. East London Robotics' Slowloader allows you to load ZX-81 programs into a ZX Spectrum. The Slowloader adapts itself upon loading to whichever type of Spectrum is in use. CONCLUSIONS Perhaps if Sinclair had put a little more thought into primary design, devices like the Abacus controller probably would not be necessary. Its boost to the Spectrum's amplification is useful, as is the capability to switch it off when the keyboard bleeper gets on your nerves. Once Kempston's joystick is fitted, nothing else can be added to the connector. But what sort of peripheral would you use in conjunction with a joystick? By putting a stackable connector between the Spectrum and the stick's connector one could test the joystick with the supplied demonstration program. The Adam adaptors are extremely useful, but consider whether or not you really want to make hardware alterations. The Adams tape controller is effectively transparent to the Spectrum or ZX-81, since it does not use any memory location either in RAM or in the I/O map. The relays involved can cope with 1A at 28V dc or 100V ac. They are sufficiently heavy-duty for many purposes like controlling model train layouts.

The Kempston joystick.