CLEAR SPEECH FROM CURRAH MODULE

The Currah U Speech module is a black plastic box which plugs into the back of a Spectrum and gives an amazing range of facilities. The unit is approximately 3in. square and 0.5in. high. Once plugged into the Spectrum expansion port, no more expansion is possible unless a motherboard is used, as it lies flat behind the Spectrum.

There are two leads from the unit. One goes into the aerial socket and the other into the MIC socket. The lead to the TV is plugged into the socket on the back of the unit. That must be done before powering-up the Spectrum.

The unit provides its own copyright message at the top of the screen when powered-up and pressing a key will also start the unit into its keyvoice mode. That is where every key used is spoken by the unit. All the keywords except the tilth (~) are spoken - even the direction arrows which come out as CURSOR. The colours, of course, are not spoken or the various modes.

The keyvoice is controlled by a variable called KEYS and can be turned-off by LET KEYS=0. That can be used directly or in the program and the keyvoice can be turned on again by LET KEYS=1. The keyvoice also works for keys pressed in the INPUT or INKEY$ unless disabled.

Another useful feature is that S$ has been allocated as a speech buffer and any LET S$ command makes S$ into a spoken string. Only letters are allowed, which is a pity, since numbers would be useful. Letters can also be used in brackets to give single or double allophones. An allophone is a sound rather than a letter in speech and words be programmed to must sound correct.

Most words will be satisfactory if typed-in directly but Os, As and some others may need a set of allophones instead. In that respect the booklet with the unit is very good, giving clear examples and a list of suitable alternatives. Unfortunately the variable KEYS does not effect the speaking of S$.

For the technically-minded, the unit contains a ULA which works on a WRITE command from the microprocessor, a ROM containing the keyword speech patterns and SP0256-AL2 speech processor. It also contains a clock for clear speech and an audio modulator to transfer the sound to the TV lead. The sound can be adjusted by using a screwdriver on the screw showing on the top at right-hand side of the box.

The U-Speech allocates itself the top 256 bytes of memory at switch-on and moves down the USR graphics and RAMTOP. More can be allocated to that buffer by the use of CLEAR. That makes it incompatible with some programs which use that space for machine code. Details of the buffer are given at the back of the book for machine code users.

Time must be allowed in all programs for the speech as it is updated only by the keyboard interrupt routine every 50ms. That also means that during SAVE/LOAD/VERIFY/BEEP and dealings with any device connected to interface one - i.e., Microdrive, RS232 or network - no speech should be in progress. That is because the speech will continue as one sound until the operation is finished.

The unit is extremely useful but time has not permitted it to be tested with any other units to see if they clash. What is presented is a very good clear speech box, with a very easy way of programming it and, even more useful, a spoken response to any key input. That might become a more than essential unit for some of disabled users.

The Currah U Speech unit costs £29.95. Currah Computer Components is at Greythorp Industrial Estate, Hartlepool, Cleveland TS25 2DF. The company is intending to make it usable for the ZX-81, BBC and other computers.

TALKBACK: SPEECH UNITS ASSESSED

When you find you get to the stage where you find yourself talkiing to your micro, it helps if it answers back!

From the time the Daleks trundled across our TV screens muttering "Exterminate, Exterminate" in their chillingly inhuman voice, I have been intrigued by speech synthesizers. At the time of writing, and to the best of my knowledge, there are six different units on the market to enable your micro to answer you back. Two others have recently lost their voice, I asked why, but the suppliers aren't talking.

The units on the market at the moment are "Sweet Talker" from Cheetah for both ZX81 and Spectrum, "Micro Speech" from Currah, "Orator" from Fuller, "Vox Box" from Datel Electronics, "Chatterbox" by William Stuart Systems, and "S-Pack" by DCP.

I contacted all of the above companies and those units that were supplied for review I sent to different reviewers for their independent comments.

For your own assessment here's what they thought....

This unit is one of the most easily obtainable, as many shops including Woolworths sell it. Packed in an eye-catching box, the unit itself is neat and lies flat on it's back when connected to the user port, unlike most peripherals which stand upright. It is sold complete with a well written manual and demo tape which also contains an adventure game featuring speech.

A useful feature is that the sound, both speech and the normal Spectrum sound, are output through the TV speaker. A drawback is that the unit is dead ended and you cannot add anything on after it. I also found that the leads which are permanently attached to it are a little short if you want to add it on after other units. The unit users an allophone system, but instead of the usual technical means of using the OUT instruction followed by the respective number. Micro Speech reserves S$ for its own use and a ROM in the unit decodes the required word.

Although the system is more related to English words, to get the correct pronunciation you have to break the word into its component syllables and reconstruct it in Currah language. "Hello", for instance, is spoken by using LET S$ = "HE{LL> (OO)" And of course there are ways to add information and inflexion to the speech, all of which make it a reasonably complex bit of equipment to use.

Currah have spent a great deal of time and effort persuading many software houses to adopt their unit for producing speech in their games, and this is obviously an incentive when purchasing such a unit. Most games also tend to use the Kempston joystick interface as a standard, and the two units cannot be operated at the same time, at least until now!

Currah once more show that they are aware of the market and it's shortcomings and have produced an extension to the Spectrum's port which will allow two (or more) units to be used simultaneously. This can be used with other items such as printer interfaces of course.

After all this, how does it perform? To be honest, I was disappointed at first. It didn't seem to live up to its promotion. The demo tape seemed indistinct and words were not pronounced clearly at all, a bit of very careful adjustment of the TV and the unit improved this slightly.

However after using it for a few days I became used to the electronic voice and began producing scathing comments to go with my games. The software companies who use it seem to get a better quality of speech and so far those who did use it used it sensibly and sparingly.

I must now admit that) find it an interesting and effective extension to my Spectrum and will make much use of it. Recommended to anyone who has an interest in going one step further.

TALK TO ME, OH MICROSPEECH

One of the great things about speech synthesis add-ons is that, for one reason or another, they usually give your computer an unrivalled capacity to make people laugh. Maggie Burton discovered that Currah Computer Components's MicroSpeech turned out to be no exception.

A MicroSpeech unit is about the size of two Swan Vesta matchboxes stuck together by their striking edges, it's matt black (you have to keep the colour scheme consistent with Uncle Clive's tastes) and very light. Actual dimensions are 75mm wide by 70mm deep by 17mm high. It clips into the printer/expansion port at the back of the Spectrum and, of course, it's compatible with the whole range of extras - printer and interface et al - so there's no worry about being unable to list out hard copies of programs while the MicroSpeech is in use.

The unit is made to function by redirection of the sound output to the TV loudspeaker. Instead, the TV lead is plugged into a hole in the MicroSpeech and an output lead from the MicroSpeech then completes the exchange by plugging into the usual TV port.

Following switch-on, it isn't long before you notice that every Spectrum key you press is 'voiced' by the computer. The fact that it says 'norrt' rather than 'nought' is just a mere distraction. You can, however, switch these 'key-voices' off by typing LET keys=0; LET keys= 1 turns back them on again. Although this could presumably be useful for someone with visual disabilities, one cannot help but envisage problems with the Spectrum's SHIFT keys - which are not voiced. It's also of little help in editing, so a blind computernik would still have a lot of problems putting his or her verbal creations into RAM.

Speechfreaks (try getting the device to say that) are likely to be only too well aware of the fiddly nature of many speech synthesis devices. Most of them are better programmed in assembler for full effect; not so with MicroSpeech. It works on the basis of an allophone set rather than the use of smaller phonemes or libraries of words and bits of words. Any contact with addresses/contents of addresses/pushing stacks is reserved for real hackers. In short, machine level work is not necessary. You can make it chat away quite happily from Basic.

Each allophone produces a distinct, different sound. The five vowels make the 'school alphabet noises' - Ah, Eh, Ih, Oh and Uh. Combinations of vowels produce different sounds. Single consonants are phonetic. Strong phonetic allophones are double consonants and complex allophones are noises like 'th', 'ch' and 'ear'. They and the strong allophones are enclosed in brackets. The brackets distinguish these sounds from groups of phonetic allophones. Leaving the brackets out of the allophone (ggg)( a strong 'G' as in GOTO) will produce something like 'g-g-g' - a new complaint known as the silicon stammer. Altogether there are 58 allophones and they're designed to cater for every sound in the English language. Naturally, heavy compromises are necessary and, for instance,'q' and 'x' are not recognised because they can be made up of combinations of other sounds - 'kw' for 'qu' and 'ks' for 'x'.

Thus, in making up a sentence it is necessary to see the word exactly as it is pronounced, not as it is spelt. Even then it's possible to get the wrong end of the stick - 'th', for instance, should be '(dth)'. But there is also a '(th)' - a slightly softer '(dth)'. Knowing which to use is all down to trial and error.

Those whose knowledge of Sinclair Basic is reasonable should get to know how the MicroSpeech works pretty quickly. And it's possible to build up libraries of useful phrases by putting them in string variables (from Basic all words to be spoken are treated as strings). You can then use these over and over again, like this:

5 REM OKAY WISE GUY THIS iS iT
10 LET a$=" (oo)K (AA)"
20 LET b$="w(ii)z (ggg) (ii)."
30 LET c$ = " (dth)is iz it "
40 LET S$ = a$ + b$ + c$

Line 40 is the line which does the talking and S$ is a reserved variable which, when used, sends all those carefully planned allophones whizzing off to the speech buffer. But note that if the MicroSpeech doesn't recognise one part of a LET S$ statement it'll maintain an eerie silence or skip that phrase and jump to the next one it does understand. Notice the use of the capital 'A' in line 10. Using a capital letter on a vowel raises the pitch at which that vowel is pronounced. A limited amount of intonation is possible in this way - but beware; one of the best ways of confusing the MicroSpeech is to use a capital consonant. Even the versatile human voicebox can do little about raising or lowering the pitch of the sound 'P' for instance.

Pauses of various kinds can be included with the help of a space, comma, apostrophe or full stop. The apostrophe is useful for giving emphasis to a bit of a word, as in d(oo)n' (tt) - don't - by shoving a discreet and very short pause in where the apostrophe is placed. The space separates words, the comma, phrases, and the full stop separates sentences. A PAUSE command has to be placed between each LET S$ command and the one following. This makes sure the computer can detect each one. If a PAUSE is left out (it need only be PAUSE 1) the S$ command following where the PAUSE should have been (with me so far?) is omitted.

One complaint is the amount of interference the MicroSpeech causes on the TV. It makes it more difficult to tune in properly and all the time the machine is switched on, the TV performs its own impersonation of a beehive. This varies in intensity according to what's on the screen and is at its worst when a program has been listed.

Some of the voicing is very unclear. For instance 'g' and 'd' sound very much the same and there's no real way to get nuances of pronunciation into what the MicroSpeech will say. So don't expect it to read too well from Shakespeare or the Gospel of St John - although it's been tried, with predictably silly results. Certainly experimentation is necessary to work out some words although the small-but-perfectly-formed manual is fairly helpful in this direction, providing details of how some of the keywords are voiced and giving some pretty stock-in-trade examples.

It's also possible to connect the MicroSpeech to a tape recorder, through a line lead adjacent to the TV connector. Using this it's possible to record speech as it leaves the computer - just plug the lead into the 'MIC' socket of the tape recorder. And by the same token, output to a hi-fi is possible by connecting the same lead to the auxiliary socket of an amplifier.

The speech chip used in the Currah MicroSpeech is General Instruments' SP0256-AL2. Currah and GI worked quite closely together on the project and the end result (at £29.95) is an absorbing, easily used add-on which represents pretty good value in an age of destitution and hardship. It's available, Sinclair-style, by mail order from Currah and comes complete with a demo cassette. It can also be bought through Spectrum Computer centres, Computers For All and Comet, W H Smith and Boots will probably get round to it eventually as well.

Several software houses have quickly cottoned on and a good list is available of packages which make interesting use of the MicroSpeech's capabilities. This includes, from Bug-Byte, The Birds and the Bees, from Artic, Talking Chess, and from Romik, a version of 3D Monster Maze. To date, claims Steve Currah of Currah Computer Components, "about 20,000" MicroSpeech units have sold, mainly to stores. No wonder - it's good fun and great value.

THE INGENUITY OF THE PERIPHERALS MANUFACTURERS HAS CONTINUED AND SINCLAIR RESEARCH FINALLY LAUNCHED THE MICRODRIVE. STEPHEN ADAMS REVIEWS ANOTHER INTERESTING YEAR FOR SINCLAIR USERS.

INGENUITY BEATS SPECTRUM LIMITS

Stephen Adams summarises the add-ons.

The biggest blow to users of non-Sinclair-produced equipment was the announcement of the Spectrum. It knocked most memory-mapped add-ons on the head, as no provision for those devices had been made. That was because, unlike the ZX-81, there was no way of turning-off the internal RAM from the expansion port. The only thing left was for producers to put things in the input/output map or to supply RAM packs or RAM upgrade kits.

The I/O map was already full of Sinclair devices, allowing the use of only eight separate devices, if they wanted them to be compatible with the Microdrive. Nevertheless, ingenuity brought forward a large number of new devices after the initial shock had worn off.

RAM kits for upgrading the 16K Spectrum to 32K are now readily available for about £21. Fox Electronics, for example, supplies a kit for £20.99 and it has instructions on how to improve your TV display. They are easy to fit and now have simple instructions on what to do, if you can overcome the fear of opening the case. The kits are usually identical to the proposed Sinclair upgrade but will fit only on model 2-type Spectrums. East London Robotics can also supply an extra 64K kit which is paged.

For those with a model 1 Spectrum, identified easily by the grey keys, there is the choice of an add-on board made by Downsway Electronics or the Spectrum 32K RAM pack by Cheetah Marketing. The Spectrum RAM pack will also fit on to any other Spectrum, as it plugs into the expansion port.

Another memory-mapped device available this year was in a surprising place, inside the Spectrum 16K ROM space. It was the Orme Electronics ROM containing RENUMBER, block delete of Basic lines and many other usefiil routines in a 2K ROM. That can be very useful, as it is immediately available on power-up.

Sinclair has also provided new devices in the ROM space, which should please hardware and software users. One is the Microdrive Interface One which not only contains the controlling ULA and hardware to run the RS232/network/highspeed cassette Microdrive but an extra ROM which can be used to write your own Basic commands. The other is the ROM cartridge system available with Interface Two.

The RS232 can handle a printer easily with its limited handshaking ability but Still is limited for input from an RS232 device, as all that is under software control and not a hardware chip. The network is a very simple arrangement which allows you to talk between 64 Spectrums but I have no doubt that someone will write similar software to use it with the ZX-81 through the cassette sockets. Two books which should help in this respect are those by Andrew Pennel and Dr Ian Logan.

The Pennel one also contains an ON ERROR GOTO machine code routine which should trap 90 percent of Basic errors and send them to a program line to deal with them.

Sinclair has also launched the Interface Two, containing two joystick sockets which will operate the first or last set of five number keys. That will mean that software will have to be re-written to use Sinclair joysticks, as the accepted standard at the moment is the one set earlier in the year by the Kempston joystick interface which operates as an I/O device, depending for its decoding on A6 only being low.

Much software has already been converted to use it and I cannot see software writers wanting to do it all again. Programmable joysticks are just starting to reach the market, which will eliminate the need to rewrite the software.

For the Spectrum and soon the ZX-81, the Stonechip one seems to be best. For ZX-81 and Spectrum users, a cheaper hardware-based version, the Pickard controller, can be used as it fits both computers by plugging into the keyboard sockets. The AGF version uses crocodile clips to set up the five keys to be used; it is a little unstable but it plugs into the edge connector and does not require entering the machine.

The Interface Two also has a single ROM socket which allows you to use Sinclair-designed cartridges. It is not known whether software suppliers will want to try to fit normal ROMs to a port like this. That, and the fact that recording Microdrive cartridges is a slow process, will limit the amount of software available from software manufacturers on Sinclair devices. EPROM software for ZX-81s is available from Eprom Services and Audio Computers.

Both, however, concentrate on the machine code user and not the games player. The fall in price of the ZX-81 and the amount of hardware available for it has started to attract the business user as a control processor for a robot or controlling some industrial process.

That is because it contains all the requirements of the development system on one board - Z-80-A, one of the most popular processors, working at 3.25MHz, TV interface, cassette interface for program storage, alphanumeric keyboard, Basic as well as machine code monitor for designing programs, and an expandable memory map and I/O map.

There is also a wide range of machine code assemblers, disassemblers, EPROM cards and blowers, RAM, battery-backed memory already available, costing just a few pounds. That to the industrial process manufacturer is peanuts, as a development kit from a chip manufacturer would cost more than £200 with far fewer facilities. The ZX-81 costs only £45 with a massive 16K memory included.

Plain-paper printer interfaces for the Spectrum abound and Tasword, the word processing program, can work with most of them. Hilderbay and Kempston provide software-driven Centronics versions, while Morex provides both RS232 and Centronics outputs. Deans also introduced its version of the Timex printer, which uses a much better paper than the Sinclair, gives a clearer print in both black and blue ink, and will use Sinclair commands to control it, so there is no need for extra software.

Printers and other hardware devices make the software "come alive" and that combination makes the Spectrum a very powerful business computer.

That is the most important event of the year, as the more software which is written to use the large amount of hardware, the more that hardware will be used. Voice output units, modems - to talk to other users or databases over the telephone - RS232 interfaces and light pens all rely on good software to make use of them.

The Cheetah Marketing Sweet Talker, for instance, works better because it is accompanied by an instruction tape which not only demonstrates how to use the unit but also shows the user how to structure programs to make it easier to use in their programs.

Modems from Maplin, Ambit and Micronet - for Prestel - will allow users of the Spectrum and, in the first two cases, the ZX-81, to talk to many other computers. Some of them will be other types of computers, like the BBC and the Commodore 64. The others will be maintained by public and private companies which maintain large amounts of information and programs on their computers.

Micronet 800 is a database maintained on Prestel computers as a 24-hour-a-day, seven-day-a-week computer club. It has hints and tips on Spectrums - ZX-81s at the moment cannot use the system - as well as news, free programs and a mail box facility. Keyboards and consoles also have been making their presence felt as ZX-81 and Spectrum users want to upgrade their machines. Plastic cases from W H Smith are about the cheapest containers at £3.99 and will take a ZX-81 or Spectrum, as well as a few add-ons. The d'Ktronics keyboard and case or that from Fullers appear to be the most popular but neither will allow the use of the Microdrive interface without taking it out of its case.

The Filesixty button set is a cheap alternative for ZX-81 users which gives the advantage of spring-loaded keyboard the same size as that of Sinclair, but without costing more than £10.

Colour for the ZX~81 is now available in a simple form for all PAL television users - that is, most of Europe. The black box requires only two wires to insert between the modulator and the breaking of tracks and can be re-connected if required. The rest of the box plugs into the back of the ZX-81 to give black characters on a choice of 16 coloured backgrounds or coloured characters on a black background from DDC. It is also more stable than the Spectrum and requires no extra memory to use it. It will work even on a 1K machine.

One device which requires extra memory is the excellent High-res screen - 192 by 256 pixels - and user-definable graphics package made by Nottingdale Technology Centre. It uses the ZX-81 internal 1K RAM for its system variables and 6K of memory for the storage of the screen in the program. No internal wiring is required, as the unit plugs directly on to the back of the ZX-81.

For the Spectrum, a unit has appeared which will be of great delight to children and disabled users. It is the Currah microSpeech unit which plugs into the back of the Spectrum and, on command, will speak the key pressed. That happens during program input as well as INPUT and INKEY$.

It requires no programming of the speech by the user. Speech output can also be programmed by using S$ to contain the allophones - sounds which make up words - which are then spoken immediately. Thus input and output can be spoken rather than read.

Tapes have been causing problems ever since the ZX computers came into existence; the Spectrum is better than the ZX-81 but still can be improved with some extra hardware.

Tape filters and switch-controlled SAVE and LOAD devices are available from several firms, like Abacus and Elinca. There have now been three Spectrums produced by Sinclair. The model is, which can be identified by the grey keys or by looking through the expansion interface and seeing an IC socket on the left-hand side; the model 25 have the large, black, ROM chip there. Those Spectrums need their extra 32K of RAM mounted on a printed circuit board before they can be put into the computer. There are no Sinclair RAM boards available for the machine.

The model 25 were re-designed completely by a computer and the ULA was changed to get rid of an extra 1C which had to be inserted in the model is, due to a design error. The extra 32K of RAM which can be added to 16K machine now requires only chips to be plugged into sockets on the board. Model 1s and model 2s have had to have an extra transistor fitted to prevent a clash between the keyboard and the ULA TV interface.

The latest model 3s have also had their internal circuitry re-arranged and the ULA updated to give a wider tuning range on TV sets. It has also caused some software problems, as the keyboard inputs are no longer held to binary l - + 5 volts - when not in use. That was done to reduce the power 1 requirements of the ULA.