The Sharp MZ5600 could knock Apple's Mac and Lisa computers off their perch. Trevor Jenkins puts this new micro on the operating table and gives it a thorough examination

First announced at last October's London Business Equipment Show the Sharp MZ5600 range has since attracted a great deal of interest - so much so that not all the options were available for review. Sharp claims they're selling too fast.

Immodesty apart, Sharp has come up with an impressive micro, and made a sensible decision in not attempting to copy the IBM PC, although there are, of course, certain similarities. Both are based on the Intel 16-bit processors, the IBM on the 8088 and the Sharp on the 8086, which means the 5600 has a 16-bit data bus compared with the eight bits of the IBM.

If the sort of work you have in mind is essentially 16-bit, the Sharp runs faster. There was a time when an 8-bit system used an 8-bit data bus, operated on 8-bit data and was easy to categorise. Now we have 16-bit systems with an 8-bit bus operating on 16-bit data, and are headed for the 32-bit system with a choice of 32-, 16- or 8-bit data buses.

The 8086 processor may not have the best structure or instruction set available, but as it was among the first used in micros, it does have a large selection of software available for it.

Sharp has gone against the trend set by its competitors with 8086/8088-based systems in the size of memory provided as standard. Applications for the 8086 range have been memory hungry, and the manufacturers have xploited this by their entry-level systems not having quite enough memory to run the software package you need efficiently or effectively. Most of these systems start at 128L; Sharp, however, stands alone in starting you off with 256K. If you still need more memory, there is an expansion board available.

Program memory space is not affected by the video RAM (which is separate), although it does come out of the megabytes the 8086 is capable of addressing. The video RAM is normally 96K, but is expandable to 128K. The 96K is sufficient for monochrome display, but must be expanded if you want to exploit the colour capability.

The video RAM is accessed by both the processor and an NEC7220 graphics processor chip. The latter gives the MZ5600 series sensational graphics capability: it performs nearly all the graphics functions you might expect of a pricier microcomputer. Windowing, zoom, lines, circles and user definable characters are supported. Many sophisticated professional graphics devices are now appearing which use this chip. The demonstration system has some excellent examples of how to get the most out of this processor - multiple moving windows each with different picture elements, for instance.

Sharp has also included a programmable sound generator, supported by special statements in the Basic interpreter. The manufacturer scores over other systems here by also including a very necessary volume control, which is easy to find into the bargain.

I don't usually like such accessories but I was tempted to use it all the time with the review system.

While on the subject of noise there was excessive noise from the hard disk - not just when first switched on or when in use - but continuously. Sharp says production models will have some filtering to reduce this, but ask for a demonstration in a quiet place anyway.

Also whenever the floppy was accessed, this drive created a temendous noise, reminiscent of an old manual typewriter. Is it safe to assume that solving the noise of the hard disk will also remedy the floppy drive problem?

The system is contained in a metal cabinet slightly smaller than an IBM PC's. Unlike many other systems, the metal box stops interference from the electronics to surrounding equipment; it also protects the equipment in transit.

The review system came with one 600K floppy disk and a 10Mb hard disk all in the main cabinet. Apart from the keyboard and monitor, all the electronics are in this box.

On the front of the box is a socket for the keyboard, the optional mouse plugs into the keyboard. Also on the front are the volume control and the reset switch. The latter has been recessed into the metal work, so pushing it accidentally is impossible. A nice feature is that the on/off switch is out of the way on the side of the cabinet far away from the reset switch, and any exterior connectors which are all on the back. The power switch is also recessed.

The sockets on the back are inset making them difficult to dislodge. There are two monitor sockets, one for black and white, the other for colour; this implies it may be possible to run the two together, but as the colour monitor was not available for review, I was not able to confirm that. There is also an additional socket for the keyboard. One serious criticism of these sockets is that both RS232 connectors are not the normal 25-way sockets, nor do they conform to the newer RS423 standards, so adding a printer will need some thought. Sharp's documentation tells you how to do this, but the plug is not the normal size.

A separate Centronics printer port is also on the back of the case. A socket to connect an external floppy disk is present but this option was also unavailable for review (and ominously is not mentioned in the price list).

I would like to have seen some power supply sockets on the back, which would have added to the superiority of the system by enabling the monitor and printer to be powered without needing additional mains plugs and wires.

The quality of the monochrome monitor supplied matched that of the system. A swivel stand allows the position to be adjusted. The keyboard is modelled on the IBM PC, but has a better feel and a slightly different layout. It is thinner than IBM's, with small feet that are either up or down, rather than variable.

An impressive array of software was included for the review, the mainstay being CP/M-86. Sharp has made very useful additions to the utility programs and overcome some of the problems inherent in CP/M-86. Several celebrated packages came on hard disk, but without manuals. DBaseII, SuperCalc and Wordstar were supplied and the list of other software ready for the MZ5600 shows that Sharp has got its act together on this score too, unlike many others. MSDOS and CP/M-86 will be supplied free of charge with the machine.

Sharp has not forgotten the 8-bit customers, and the Basic interpreter accepts programs written for those earlier machines. Two conversion programs are provided to read an 8-bit system disk and convert the programs to the new format. This Basic is excellent, despite a few idiosyncracies.

What you should remember is that this is not Microsoft Basic (although GWBasic will be available early in 1985). So, a number of control structures are not present for the programmer. For example, there is no WHILE or REPEAT statement - only FOR/NEXT loops are allowed. A little worrying are the inconsistencies between this version and any other. The most irritating is that the PRINT statement only works on the printer. To print items on the monitor the DISP (display) statement comes into play. Then there are the strange forms of the single-line IF/THEN/ELSE statement. Lastly, the interpreter distinguishes between the cases of letters.

The capabilities of the 7220 graphics chip are covered by many statements in this Basic. Control of each separate window can be established with one statement; scrolling of any window can also be done in one command, in either up, down, left or irght. The 7220's characters display can use user-defined symbols, in an easier way than the BBC Micro does, the functionality is the same but more direct.

Presentation of output can be enhanced using a very powerful PRINT USING statement which allows printer control character sequences to be included in the output. On the monitor it is possible to put up a grid of various sized boxes with a Table command, which will impress anyone who uses the Sharp for producing management reports.

A number of statements are dedicated to the function keys to make full control easy. One of these is used for debugging and correcting erroneous programs.

Programming language purists may be upset to discover that some mathematical functions don't use the usual function syntax. However, there are redeeming features: a full set of floating point functions, and the ability to switch between degrees and radians for the sine and cosine functions.

More upsetting to everyone may be the licence agreement between Digital Research Japan and the buyer. The terms and conditions are ludicrous. 'Digital Research Japan makes no warranty of *any* kind' runs one, and 'the entire risk as to the quality or performance is with the purchaser' warns another. So, if CP/M-86 does not work on arrival, that's just tough. Come off it, Digital Research, this won't curry any favour with your customers. In fact, I would like to refuse to sign my agreement or even to purchase CP/M-86 - perhaps that's why it comes free. DR may be trying to protect its investment, but there's protection, and there's ripping people off.

The usual 16-bit documentation comes in an IBM-style binder, with a box to store it in.

The manual's presentation is good, and the usefulness of the documents ranges from barely adequate to almost excellent.

Since only CP/M-86 manuals were supplied my comments are limited to those books. In my experience, it is likely that what it said about DR's offerings will also be true of Microsoft's MSDOS manuals. For the latter, I was provided with some photocopied pages of an MSDOS manual, relating to the Sharp and my comments below concerning its CP/M-86 documents would seem to be true of this manual too.

Software suppliers tend to think only in terms of quantity rather than quality of documentation, and that's true here. The impression that both Digital Research and Microsoft give is that they do not understand their audience.

The CP/M-86 documentation (a programmer, system and user guide) is as issued by DR with the necessary addendum and errata sheets. For those who have already seen these manuals don't despair, Sharp has put great effort into reproducing them. The contrast of the copies is very high overcoming the faintness of the originals.

Sharp has added a separate manual to these three to cover its additions to CP/M. Unlike DR's, this is typeset, and the examples are clearly laid out and well chosen, though some of the accompanying explanations are obscure. There is also a user's manual which includes concise details of the hardware, though data sheets for the various devices would also have been welcome. A systems integrator would need them, as would anyone trying to use the sound generator or the 7220 from a non-Basic program. The Basic interpreter does provide access to them, but not everyone wants to use Basic, even one this good.

The Basic interpreter documentation is among the best for this language. The book has a small introductory section which leaves teaching the language to the many books already available; what it does cover are essential details of the implementation for those who have used another version. The manual is well laid out, with each Basic keyword on a separate page, along with the formal definition of the statement and examples of each possible format included. There are notes in explanation of the function.

What lifts this manual above the rest is that in addition to the explanations, there are helpful tips on the use of the statement with good examples, even if they are a bit laboured. There are also footnotes to answer those questions most of us have never wanted to ask until we're kept awake at night searching for the answer.

The only niggling problem with the Basic manual is that it's not in alphabetical order, but it does at least have an index of keywords.

Two quick reference cards are included in the package: first, a DR pocket manual which includes the Sharp extensions. This covers most of the contents of the DR manuals, but in very meagre detail - a deficiency best demonstrated by the error message section which explains self-explanatory errors. The section on BDOS function calls is much too cramped - it needs much more space (perhaps given up to those error messages); however, it is useful and can save time.

Basic also has a quick reference card, organised alphabetically; unfortunately, some of the notation is not explained (such as the use of input/output unit numbers). It has small examples with parallel explanations in addition to the format of each keyword.

If you want some compatibility with an IBM but are not too concerned exactly how much, or you want to be happy in your use of a machine, relying on the documentation to tell you what you want to know again, then the Sharp MZ5600 is your machine.

When DR's GEM package becomes available for the MZ5600, it is going to put up a good fight with Apple's Mac and Lisa machines - that NEC ship does some startlingly good graphics.

All in all, this is probably one of the best 8086-based machines at this level of the market today and deserves a lot more attention.