TACTILE TEACHER

For many applications the standard QWERTY keyboard is far from ideal. The Touchmaster, from Touchmaster Ltd, is one way to make data input easier.

It is a pad with a flat surface on which, as you draw, the position of the pen is returned to the computer. By using a number of different overlays different parts of the pad can be made to represent different things and so the keyboard can almost be dispensed with.

The Touchmaster is sold as a complete package of pad, power supply, stylus, interface and a drawing program. Interfaces are available for a number of computers - Spectrum, BBC, Commodore 64, VC, 20 and Dragon - so if you change your computer you need only a new interface. As the package costs £149.95 that is a definite advantage.

The Spectrum interface is a standard black box which fits flat into the user port. An extension edge connector is provided on the back and a 3ft cable connects to the parallel socket on the pad. The pad also has a serial connector, possibly useful for a QL version, and a socket marked 'Foot Switch' but there is nothing in the instructions about that.

The drawing program, called Multipaint, has a number of features but does not compare too well with other drawing programs. On the plus side, apart from entering text and loading the program, the keyboard does not have to be used, which consequently speeds drawing. When drawing freehand you can alter the 'brush' to give different thicknesses and styles.

The usual facilities of filling areas, drawing circles, boxes and polygons and changing the attributes are available. You can load and save screens but for some reason that facility could not be made to work. What it lacks are the grid overlays, magnification, scrolling and flipping of the more comprehensive programs. You can only draw on the top 22 lines of the screen and, as there is no grid on the pad overlay, you can easily lose your position.

Touchmaster sells a number of other programs for use with the pad. Of the three we look at - Simon's Shapes, Simon Saw and Simon Says - only the last one would hold a child's attention for long.

Simon Saw entails finding the correct jigsaw pieces to make a picture. If you succeed you can feed the cat. In Simon Says you build up a cartoon style photo-fit face. The computer then moves randomly some of the features and you have to repeat the sequence. You do that by pressing either the feature or the word on the pad. Then you get to feed the by now grossly overweight cat.

Although the instructions say you can run the Touchmaster using your finger, instead of the stylus, it needed more pressure than a small child could give. That may be because it was new but try one out if you are buying for your children.

The only comparable product to the Touchmaster is the British Micro Graphpad. The Graphpad is about £6.00 cheaper and has a superior drawing program but can not be swopped from one computer to another and, as yet, does not have any additional software. If Touchmaster can improve the quality of the software it could better realise its potential. Touchmaster Ltd, PO Box. 3, Port Talbot, West Glamorgan, SA13 1WH.

TOUCH AND GO!

There've been several digitisers on the market for the Spectrum, but only the Touchmaster claims to be a keyboard replacement. Henry Budgett puts theory into practise - check out his findings...

We've seen a few digitisers around for the ZX Spectrum, but only one that's been promoted heavily as a replacement for the keyboard! The Touchmaster graphics tablet also claims to operate (with a suitable interface, of course) with almost all the current home computers.

UNDER PRESSURE?

Based on an A4-sized pressure sensitive membrane, the Touchmaster comes in a neat grey case measuring some 350mm by 330mm by 35mm. The back of the case is raised slightly so that it tilts the tablet to form a convenient drawing surface. All connections to the tablet are at the rear, and it's here that one of the differences between the Touchmaster and its rivals becomes obvious.

Power is supplied from a plug-in transformer and a single red LED shows that the power is on... but there's no power switch fitted. Presumably, to allow the tablet to be used with as many home computers as possible, there are both parallel and serial interface sockets on the rear panel, together with an unexplained socket for a 'foot switch' - should you want to play 'footsie' with the device, maybe? Whatever it's for, it's not mentioned in the accompanying hardware manual.

Using the same sort of membrane technology as ZX81/Spectrum keyboards, the tablet provides a 256 by 236 point resolution. The upper, carbon fibre, layer is held away from a lower resistive film by an insulating mesh. Thus, if you apply pressure to any point on the upper layer, the two layers are forced into contact; the actual pressure point is determined as a co-ordinate by a microprocessor built into the tablet that scans the top film in one direction while scanning the lower resistive film in the other. Once a point of contact has been established, the co-ordinate is relayed to the Spectrum via the parallel interface. (On a point of interest, it's worth noting that the Touchmaster's resolution is well below the Hi-res screen displays on several of the home computers it's available for; for example, it'll be impossible to resolve the Touchmaster's output to a single dot on the BBC Micro in Mode 0).

A plug-in interface is provided as part of the Touchmaster package to connect it up to the Spectrum. Along with a generous length of ribbon cable, the 'black box' interface unit contains a standard Z80 PI A chip; an extension connector is provided out the back of the unit for additional peripherals. The unit's definitely over-sized and projects far more that it needs to from the Spectrum's rear, but this is no doubt the result of using a standard box rather than poor design.

THE BITTER PILL

As a piece of hardware, the Touchmaster tablet would seem to have a lot going for it - especially when compared with its rivals like the Grafpad. It's built robustly and offers a full A4-sized drawing area that can be used for both drawing and the touch selection of menus. I suppose it could be considered an advantage that the Touchmaster, with new interface and software, would work with another computer - should you commit the cardinal sin of attempting to upgrade from the Spectrum (Hah, no way! Ed.).

It's a shame that the documentation should be so poor compared with the standard of the tablet itself; the hardware manual covers the connection of the tablet and provides a number of simple Basic programs to read co-ordinates from it... but little else. Touchmaster's manufacturers are bringing out a range of software called Touchware, designed specifically for use with the graphic tablet; games and educational programs seem to form the bulk of the planned material, but the real proof of success will come if independent software houses decide to support it as well. Of course, the main stumbling block will be its price - nowadays, an independent hardware add-on has to justify its relatively high price to an awful lot of users before the market accepts it as standard.

The Touchmaster graphic tablet does provide users with the means to copy drawings and diagrams from paper to the Spectrum's screen, although the serious artist will probably be forced to re-load the picture under control of something like Melbourne Draw to make the final version worth close inspection.

As for replacing the keyboard with a Touchmaster... well, the keyboards's not that great, but I still have my doubts. Until there's adequate software support, the use of the tablet would be restricted to the selection of on-screen options or simple games control... and you'll still need the keyboard for data entry, and loading up Multipoint and the like. It's a nice thought to be going on with…