| ★ HARDWARE ★ LES PC D'AMSTRAD ★ AMSTRAD PCW 8256 ★ |
| AMSTRAD PCW 8256: PLOP ! UN NOUVEL AMSTRAD (Hebdogiciel) | AMSTRAD PCW 8256 (Popular Computing Weekly) | NEWAMSTRAD 8256 EXPOSED | AMSTRAD PCW 8256 (CPC Magazin) | AMSTRAD PCW 8256 (Byte) | Amstrad PCW8256 |
Amstrad's period of prolific manufacturing continues with the PCW 8256, a good-quality, great-value word processing system that includes a printer in its $1,500 price tag. Is there sufficient support in the 'serious' market to do it justice? Peter Bright conveys his impressions. Now, with its new machine, it seems to have taken its good-value image to new heights — a word processor with CP/M, a disk drive, 256k of RAM, a monitor, Basic, Logo and a printer for under $1,500. Hardware The name PCW stands for Personal Computer Word processor. It is made up of three separate units — the main system box, a keyboard and a printer. All three units will be supplied in one large cardboard box much like a domestic TV. Even in the business market, the idea of including a printer in the price of the unit is unusual, and at this price level it is unheard of. The main system unit houses the monitor, the disk drive and all the electronics, including the power supply. It looks very like a portable television, and I wouldn't be at all surprised if the casings started out as an Amstrad portable TV. It also sits on what looks like a tilt/swivel stand except that the review model didn't tilt or swivel. Most of the front of the main unit is taken up by the monitor screen. To its right are spaces for either one or two disk drives mounted vertically. The usual configuration is for the machine to be supplied with one disk drive in the top slot, with the bottom slot containing the PCW badge. The back of the machine is quite bare: all it houses are power-in, a special Amstrad printer interface, and an edge connector onto the main PCB. There is also a 24-volt power-out socket to drive the printer. The edge connector exists primarily because Amstrad will be offering an RS232/Centronics parallel printer module which will plug into the edge connector and slot into a recess on the back panel of the main unit. The final interface on the main system unit is a DIN socket on the side panel for the keyboard lead. You get inside the PCW in the same way that you would get inside a televi sion — remove the screws and take off the back panel. Most of the internal space is taken up by the monitor tube and high-voltage electronics. The digital section consists of just one surprisingly small PCB. My initial reaction to this PCB was how small it is and how few components it uses. It has been totally redesigned, and uses significantly fewer components than either the 464 or the 664. The main PCB contains a total of 1 7 chips. Of these, eight are 256 kbit RAM chips and another five are TTL drivers for the printer interface; this leaves just four chips to do the serious processing. These consist of a 4MHz Zilog Z80 processor, an 8041 printer controller chip, an NEC 7658 disk controller, and a large dedicated gate array. In addition there are sockets for another eight RAM chips, although Amstrad says that it has no intention to fill them. Although the Z80 processor can usually only access 64k of RAM, the PCW makes full use of its 256k by bank-switching sections of RAM. This is usually handled by the CP/M Plus operating system. You may have noticed that the above list doesn't include any ROM chips. This is due to the PCW being without any ROM as such — everything is loaded off disk. In order to do this you obviously need some kind of disk bootstrap loader, so Amstrad has used the 256 bytes of mask ROM available on the 8041 printer controller to squeeze one in. The gate array is interesting in that it is mounted above a hole cut in the middle of the PCB, with its legs spanning the gaps on all sides between it and the main board. The result looks odd but is apparently easy to align for manufacture. The low component count coupled with the fact that the PCW is manufactured in the Far East and then shipped over, means that the system is probably cheaper to produce than the 464. The system has been designed to work with either one or two disk drives. Initially, Amstrad will be shipping each unit with one 3in 1 70k disk drive; an extra drive can be fitted at a later date if required. Amstrad also plans to sell a 1 Mbyte (720k formatted) double-sided, double-tracking 3in disk as an extra to fit into the spare disk space. This should be available later this year. As I have stated, it is unusual for a computer manufacturer to include a printer in the price of the machine. Amstrad hopes that one of the PCWs main selling points will be its word processing capabilities, so it follows that a printer is a good idea. The printer casing matches the appearance of the rest of the system, and looks like a fairly standard 80-column dot-matrix unit. In fact, true to Amstrad's style, the printer is as basic as it can be while remaining capable of doing its job. Most printers contain a processor and ROM to hold the character fonts, as well as control electronics for a Centronics printer interface. Amstrad buys in the basic printer mechanism without any control electronics at all; all printer control is done by the printer controller in the main system unit. This extends right down to telling the pins on the print head when to strike, which means that the only electronics necessary for the printer itself are a few TTL drivers to interface it to the main unit. The printer interface is non-standard and achieved via a short length of ribbon cable. The advantage is that it makes the printer cheaper to produce. This economy even extends to ditching the Online, Line-feed and Form-feed buttons that are usually found on printers; these functions are accessed under software control from the main unit In use, the printer is very good considering it's free. It can handle both friction-fed and sheet-continuous stationery. The tractor feed unit clips onto the top of the printer and is driven via a gear from the roller. A nice feature is that if you are using single-sheet paper, the printer will automatically roll the paper so that it is aligned at top-of-form as soon as you pull out the bail bar; this saves you having to rotate the roller by hand. Our office typewriter does this, but I've never seen a computer printer do it.
Two type qualities are offered: draft which is fast; and high-quality which is slow but very good in terms of type quality. This obviously isn't up to daisywheel standards, but I wouldn't be ashamed of it. The printer can also reproduce graphics from the screen, either by using the built-in graphics dump routine or by using the GSX drivers supplied. The pin patterns for the letters are all stored on disk, so theoretically you should be able to create your own type-styles. However, unfortunately they are stored in a compacted form and aren't too easy to get at. As previously mentioned, all printer control is achieved via software from the main unit. If you are in the word processor, you can control all the printer's functions from there; but if you are in CP/M ora generic applications program, you can use the key on the keyboard marked 'PTR'. When you hit this key, a printer control menu is displayed on the last line of the main display. Using the'+' and '—' keys, you can set and unset on/ off line, top-of-form, line-feed and formfeed, toggle high-quality/draft print, toggle on or off the paper-out detector and reset the printer. These functions are very easy to use when you remember that you have to control the printer from the keyboard rather than by pressing buttons on the printer. Overall, I was impressed with the printer. It is slightly slower than modern dotmatrix printers, but the quality can be good and it's free. Unlike previous Amstrad machines, there is no choice of display with the PCW — a monochrome green screen is what you get. No colour is available. The display is built into the main systern box; in fact, it is the main system box. At 14 inches the display tube is larger than average, but like other Amstrad systems it is based on television technology. This means that the display quality isn't up to pukka monitor standards, but is still quite good. I had no trouble using the screen on the review machine, although a lack of shielding on the pre-production unit did cause some display surge. My main worry was that the tube had no anti-glare coating, and consequently could be hard to read when facing a window. As it uses a large 1 4in tube, Amstrad can fit more characters on the screen than usual. Most systems have 80-column by 25-line displays; the PCW has 90 columns by 32 lines, which gives 50 per cent more characters onscreen than usual. This extra size can be useful: in the word processor, for example, you can extend the number of words display-able onscreen. Some CP/M programs can also be configured to take advantage of this extra room — I saw a version of Super-Calc 2 which managed to display more cells onscreen than it normally did. For CP/M programs which can't use the larger display, Amstrad supplies an 80x 25 screen driver. The system is also supplied with Digital Research GSX graphics interface software, and can display graphics at a resolution of 720 x 256 pixels. The display is OK rather than wonderful. It isn't as good as a standard monitor, but it's better than a 464 monochrome display. The larger size can be a real benefit for spreadsheets or word processing. The PCW is a departure for Amstrad in that its previous machines have included the keyboard in the main casing; the PCW comes complete with a separate keyboard connected to the main system by a long length of cable and a DIN plug. The keyboard unit has its own processor which scans the keys and sends the codes down the serial link. If the keyboard were a house, it would be condemned for overcrowding: a total of 82 keys are fitted into the very small unit. It's easier than usual to hit the wrong key until you become accustomed to the layout. Many of the keys are dedicated to the word processor. This gives the whole unit a strange appearance by computer standards, but it makes the keyboard a lot easier to use. The main qwerty typing section takes up most of the space to the left and centre of the unit; to its right are four function keys marked f1 to f4, and shifted to give f5 to f8. To the right of the function keys are the cursor/numeric/ word processing keys. Many of these keys have more than one function, but none has more than two — the keyboard is so cramped, there is no space between the different functional areas. Due to many of the keyboard legends being customised for the word processor, they may not make immediate sense under CP/M. Two examples of this are the control key which is marked ALT, and the escape key which is marked EXIT and which has been moved from its traditional top-left position to the right of the space bar.
One feature which I did like was the SHIFT LOCK key. Firstly, this key has a LED built in so that you can tell when it's engaged. Secondly, unlike most computer keyboards, the PCW's is disengaged either by hitting it again or by hitting one of the SHIFT keys — just like a typewriter. Some compensation for the confusing legends under CP/M is that the keyboard is 'soft', so you can set a key to return any character code. Under CP/M, you can set up different keyboard definitions and store them on disk, then call them in with a suitable applications program. This is useful, as it makes it easier to set up special keys such as cursor control and editing so that they work with normal CP/M programs. It is also useful because the system has an extended international character set which gives over 200 characters; these are usually accessed via the EXTRA key. Some of these characters are quite useful: for example, the symbol to raise a number to a power isn't on the normal keyboard legends — it is accessed by hitting EXTRA-U. Some users might want to redefine key sequences such as this. The overall feel of the keyboard is very light, although the key action felt good enough. The main problem, as I have said, is that the keys are so close together you can easily hit the wrong key by mistake, but my mistake rate fell as I became familiar with the unit. System software The PCW's main operating system is Digital Research's CP/M Plus (or version 3, as it is sometimes called). The only exception to this is the word processor, which doesn't use CP/M but goes straight to the hardware. The word processor does, however, use CP/M file structures, so word processor data is available under CP/M and vice versa. CP/M Plus was specially developed for the new breed of Z80 8-bit machines which use more than 64k of RAM, and is much nicer and more powerful than its more popular brother, CP/M 2.2. The main advantage of CP/M Plus is that it can handle bank-switching of RAM. The Z80 processor can only directly access 64k of RAM; to handle more memory than this, you have to switch different areas of RAM into the Z80's line of vision. Having said that, CP/M Plus on the Amstrad doesn't directly access all the available RAM. Of the total 256k, 116k is set aside as a RAM disk; as far as the operating system is concerned, this is just a very fast disk designated drive M. Of the remaining RAM, 61 k is given to the transient program area (TPA), and the rest is occupied by the basic input output system (BIOS), the basic disk operating system (BDOS), the console command processor (CCP) and the disk hash tables. Having the BIOS, BDOS and CCP in RAM is useful in that it allows you to load the system disk just once — subsequent disks don't require these routines to be present as they are in RAM. The 61k TPA is the area of RAM which is actually available to an applications program. At first sight it might seem that 61k out of 256k isn't that good, but in fact it is more than enough to run all the popular CP/M applications programs. Installing PCW CP/M applications programs has been made as simple as possible. One of the usual problems is working out the screen control codes in order that the program will work with your display. The PCW gets around this by putting a DEC VT52 terminal emulator between the applications program and the screen hardware, so as far as the application is concerned, it is talking to a DEC terminal. The same thing has been done with the printer. Instead of running direct to the hardware, the printer is shielded by an Epson emulator, so you set the application to think that it is talking to an Epson matrix printer. This is all very neat. In use, the PCW implementation of CP/M Plus is very nice indeed. The only slight low point is when you first boot up. I mentioned in the Hardware section that the bootstrap loader on this machine has been squeezed into 256 bytes of mask ROM in the printer controller. As it is such a tight squeeze, there is no room for any fancy boot-up screens or any error messages. When the machine is first switched on, the screen lights up. When you insert a system disk, the machine displays horizontal lines down the screen while the system is booting. If there is an error, the screen will flash or the system will bleep. You can force a retry by hitting the space bar. When CP/M is booted, it looks around the hardware to see what is there and what isn't, and adjusts itself accordingly. If you have the option serial/parallel card plugged into the back, CP/M will set itself up so that you can access it using the usual device names. The same is true if you have a second disk drive fitted. Disk drives are nicely handled on the PCW. Even if you only have one disk drive, CP/M is set up so that two virtual drives, A and B, are mapped onto the single physical drive so you can pretend to be copying from drive A to drive B. The system automatically tells you when to swap disks. The name of the current virtual drive is displayed in the bottom-right corner of the screen. CP/M Plus has so many improvements over CP/M 2.2 it's difficult to list them. The most useful are that you no longer have the dreaded CP/M 2.2 BDOS ERROR ON A type error — you now get an MS-DOS style Retry, Abort or Ignore? error; and there is usually no need to hit CONTROL C to tell CP/M that you've changed a disk in a drive. These both make CP/M Plus much easier to use. Other enhancements for CP/M Plus include date-stamping of files, password protection and an enhanced DIR command which tells you everything except how many kbytes you have free on disk. It also has a full online help facility which explains how the commands work. I loaded this onto the RAM disk for fast access when I was stuck. Applications software If you're going to sell a machine as a word processor, it's obviously a good idea to include word processing software. In the case of the PCW, this software is known as LocoScript. As the name suggests, it has been written by Locomotive Software which writes or converts all Amstrad's system software. LocoScript was written by Locomotive specially for the PCW, but it does intend to convert it for other systems soon. Although the version which I saw was pre-production and had a few features missing, it is obvious that LocoScript is a very powerful word processor. One of its advantages over a generic word processor such as WordStar is that as it was written for the PCW, it can take full advantage of the hardware, different printer pitch settings, and so on. The general user interface of the word processor is to use pull-down menus in conjunction with the function keys and the dedicated word processor keys on the keyboard. Initially I found the system intimidating, mainly because the display is cluttered and some features are hidden a few levels down. When I became accustomed to the way it works, I had few problems. When you first boot up the word processor, you are greeted by the file control menu. This is the most confusing and cluttered display on the system as it has to display a great deal of information. LocoScript stores its document files in one of eight 'groups'. Each group has a template associated with it, and each time you open a new document, data from the group template is copied into the new document. This can be useful if you generate a lot of standard letters: you could have one group called 'Letters' which puts your address at the top, another called 'Memos' which sets up the memo format, and so on. When you delete a file, it is moved to a holding area and is only physically deleted if the system needs the disk space, so you stand a good chance of being able to recover accidentally deleted files. [INCOMPLET] a page break, for example. Unlike some word processors, LocoScript wordwraps both up and down: most word processors can't move a word back once they have wrapped it into the line below. This feature is especially necessary for proportional spacing, where it is possible that a short word could have been fitted into the previous line. When you are editing text you have already written, LocoScript will only display it in the correct format when you either hit the RELAY key or move somewhere else and edit more text. This relay feature is somewhat akin to CONTROL-B in WordStar, although in LocoScript text doesn't disappear off the side of the screen as it sometimes does in WordStar. Headers and footers are of course included, plus the ability to vary the settings for odd and even page numbers. Printing can be done in background, so you can print one document while editing another. There is a slight speed overhead for this, but nothing too excessive. Overall, the word processor provided with the PCW is a very powerful piece of software, even though it does take some time to get used to regardless of its pulldown menus and customised keyboard. The only things it doesn't have at the moment are a merge print facility or a spelling checker. According to Locomotive, both of these are on their way. Two other pieces of software are bundled with the machine. One is the customary (for Amstrad) DR Logo, the other is Locomotive's Mallard Basic. Given Locomotive Software's fascination with the railways, I assume Mallard Basic is named after the old steam trains rather than a duck. Either way, it has been around for a long time on business machines and is well-respected. It is totally compatible with Microsoft Basic-80, so Microsoft Basic programs should run with no problems. The original ROM-based Basic in the Amstrad 464 is a subset of Mallard Basic with operating system extensions. The Benchmarks show that the speed is One nice feature of Mallard Basic on the Amstrad is that it incorporates sophisticated file-handling routines, including a B-Tree algorithm. With regard to generic CP/M 8-bit software, the PCW should run almost anything. I saw WordStar, dBasell, SuperCalc 2, Multiplan Cardbox and Friday! running quite happily on the machine. Documentation I was supplied with photocpies of the proof of the manuals, which seemed quite comprehensive. Apparently, the final versions will be supplied in two spiral-bound books. Most of the documentation has been produced by Locomotive Software, which makes sense — the company wrote the word processor and the Basic, and it also implemented CP/M Plus. Prices The PCW with a screen, 256k of RAM, one 170k disk drive, a keyboard and the printer will sell for under $1,500. Conclusion How can you criticise a machine that gives you 256k of RAM, a disk drive, a monitor, a printer, a very good word processor, Basic and Logo for $1,450-
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