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Help, Tips & FAQ's 

for the Amstrad PCW,

LocoScript & CP/M

 

 

An introduction to the PCW range, CP/M and LocoScript 
plus tips and answers to frequently asked questions .... from

the PCW Disc Conversion specialists 

Click here for 'Printer Friendly' version in Rich Text Format

1 - The Amstrad PCW

 

2 - LocoScript

3 - CP/M

 


1 The PCW Range

1.1 Models 

1.1.1 - 8256 & 8512

The first PCW to appear was the 8256 in 1984/5 at an initial rrp of £399 ex VAT. This comprised a green screen monitor in a grey plastic case, 256k of RAM memory, one 3" floppy disc drive and a 9 pin dot matrix printer. The disc drive, mounted vertically beside the screen, had just one read/write head so the double-sided "CF2" discs had to be turned over to use the second side. Each side accommodated 40 data tracks giving a total formatted space of 180k, of which 173k was available for data storage (the balance being used for the system track and directory). This disc format is variously known as Single Density (SD), 180k or 173k.

The limitations of the 8256's RAM memory and disc capacity soon became evident so it was joined within two years by its 'bigger' brother, the 8512. Though equipped with 512k memory, the only discernable difference in appearance was the second disc drive fitted beneath the first. Unlike the upper (A) drive, the lower (B) drive was fitted with two read/ write heads enabling both sides of the disc to be accessed simultaneously. It also worked at double the A's data packing density - 80 tracks per side - to give 720k total capacity and 706k available for data storage. This disc format is variously known as Double Density (DD), 720k or 706k.

Both the 8256 and 8512 were supplied with two single density master program discs, one containing the LocoScript 1 WP program and CP/M operating system, the other additional CP/M programs, help files and the DrLogo graphics package. 

Unlike PC printers, the PCW's printer took its power from the monitor and featured no buttons to press, all controls being from the PCW's keyboard when in 'Printer Control' state courtesy of the PTR key. Both the 8256 and 8512 were initially supplied with 'A' series printers (an A on a sticker underneath and blue paper-thickness lever inside) thence 'C' series (C on the sticker and red lever), the C's featuring an arguably better print head but decidedly inferior bail arm springs (which is why one sees so many C's ingeniously equipped with rubber bands to keep the bail arm against the paper !).

 

An elderly 8256 and a typically cluttered 8512

External printers were not directly supported but by fitting a CPS8256 unit to the rear expansion port, both a serial and a parallel port could be added. As the supplied Loco 1 didn't support external printers, this was only relevant for those who upgraded to Loco 2 or purchased other software which did eg Desk Top Publishers.

The PCW's success was not confined to the UK - they were sold abroad in considerable numbers, some even being manufactured in Spain and Germany as well as the far east, the German models particularly differing in the way the printer was connected to the monitor. 

Largely thanks to the bundled LocoScript word processor and the Mallard basic programming language, both of which were developed by Locomotive Systems of Dorking, the PCW 8256 was way ahead of its time in so many respects. It took Bill Gates a further ten years to borrow the Limbo principle and re-christen it 'the Recycle Bin' and over 20 years to come up with anything in Word which approached the flexibility of LocoScript's multiple Copy and Paste facilities.

1.1.2 The 9512 and 9512+

Although the 8000 series' dot matrix printers were flexible - allowing bold and italic in variety of type sizes not to mention supporting Greek and Cyrillic - the print quality was hardly suitable for professional use ... and Amstrad wanted to break into the small office market. The answer was the 9512 in a more stylish cream case and a daisy wheel printer. Fitted still with 512k RAM, the 9512 had a single 720k floppy drive mounted horizontally beneath the monitor screen, the latter featuring white type on black background rather than the green of the 8000 series. 

The print quality of the daisy wheel made it eminently suitable for many offices, notably solicitors and accountants for whom the lack of italic and variable type sizes was outweighed by the printer being able to take A4 paper sideways (landscape). Many writers also found the 9512 a better tool than an electric typewriter but, particularly when inspiration came late at night, the noise akin to canon-fire of the daisy wheel printer in action was not always popular with their partners vainly trying to sleep. 

Another printer-related problem was the inability of the 9512's power supply unit to handle the power surge caused by connecting or disconnecting the printer whilst the PCW was switched on. This almost invariably killed the PCW's main processor chip. A warning label was affixed to the printer but this was all too easily removed or ignored so many a 9512 suffered a swiftly truncated life from this cause.   

Recognising that the supplied daisy wheel may not be the answer to every maiden's prayer, Amstrad fitted the 9512 with a conventional PC-type parallel port from the outset and the ensemble was bundled with an early version of LocoScript 2 which did support a limited range of external printers. The second 720k master program disc contained all the CP/M and Dr Logo programs etc.

By the early 1990's, 3.5" floppy drives had become the norm for PC's (until this time they had mostly been 5.25") and 3.5" discs were not only becoming widely available but also decreasing in price whereas both the now non-standard 3" drives and their CF2 discs were becoming more difficult to source as manufacturers switched production. Amstrad's next move was therefore to fit the 9512 with a 3.5" drive and, for reasons known only to their marketing department, called it the 9512+. As will be described in more detail later, although physically the 3.5" 720k discs were the same as those used on PC's, the disc format used was still CP/M so were not readily readable on a PC. 

The 9512+'s daisy wheel printer was identical to the 9512's but a sheet feeder attachment option was made available to make it more suitable for office use and Loco 2 was upgraded accordingly to support this feature. A more innovative 9512+ option was a Canon BJ10e Bubble Jet printer instead of the daisy wheel - a radical departure for Amstrad as all hardware hitherto supplied with their PC's and PCW's had been re-badged as Amstrad, and is all the more surprising as the Canon BJ10 print engine was being used by other manufacturers in their own-badge products. 

The original BJ10e only supported the Canon/IBM printer emulation so italic was still unavailable and the difference between normal type and bold was not great but at least it offered faster, quieter and better quality print than the daisy wheel from a much smaller unit, albeit at a considerably increased price. The BJ10e was soon superceded by the BJ10ex then BJ10sx, both of which also supported the Epson printer emulation courtesy of a dip switch setting. At last, italic type was possible on a 9512 plus a wider range of symbols and accents.

1.1.3 The 9256

Computer pundits had been forecasting the imminent demise of the PCW from almost as soon as they came out in the mid 80's but, from this time (early 1990's) onwards, Amstrad now seemed hell bent on proving them right. Given that the 9512+, particularly with BJ10e option, was too expensive for many home users, the 9256 was seen as fitting the bill. It didn't. Why ? Despite it's re-styled looks, it was really only an 8256 in disguise with white on black screen and 3.5" disc drive. Despite the printer's sexy curved case, it was equally an old C series in disguise. Worse, the 9256 was bundled with LocoScript 1 rather than 2 so no external printer support and its 256k of RAM made it too restrictive for those who wanted to run Loco 2 or later. Not surprisingly, most of the production went to the remaindered merchants and were sold at knock-down prices just as had the 8256's after the 8512 and 9512 came along. 

1.1.4 The PCW10

The  PCW press of the time eagerly anticipated the new model as having all sorts of new features and so be the salvation of the PCW. It didn't and it wasn't. Effectively just a 9256 with 512k RAM, its dot matrix printer could not compete with the print quality being offered by stand-alone word processors from the likes of Canon and Brother whilst, for pure computer use, it's incompatibility with PC's (through using CP/M rather than DOS) and slow speed made it unattractive. Equally, its limitations meant that it was not a viable or realistic upgrade route either for existing 8000 or 9512 users so most of those instead chose to upgrade their existing kit by adding RAM and 3.5" drives from 3rd party suppliers .... or switch to a PC. Few PCW10's were made and, again, most ended up with the remaindered merchants. Quite why Amstrad decided to call it the 10 and persevere with the by then very dated Loco 1.5 (instead of 2 as per the 9512) will become clear one day, but it was a sad end to a ground-breaking range which had introduced hundreds of thousands of people to the delights of computing and word processing.  

1.1.5 The PcW16

This model is mentioned here for completeness of the story but it was a PCW in name only - or mis-name to be more accurate. Incompatibility with PC's was addressed by using a DOS-based disc format while the bundled word processor was by Arnor rather than Locomotive Systems so it was really more of an NC100 notepad with a monitor than any development of the PCW range. Indeed, it could not be run as a computer in the same was a 'proper' PCW so it was not an upgrade route for those with ageing or failing PCW's whether they were used for word processing or as a computer. As such, few were sold until they too found their way on to the remaindered market.

1.2 - Floppy Disc Drives and Floppy Discs  

1.2.1 The drives

As mentioned above, the 8256, 8512 and 9512 were supplied with 3" drives which took CF2 discs whereas the 9512+, 9256 and 10 were fitted with 3.5" drives and used standard PC type MF2DD 720k discs (reformatted, of course, to suit the CP/M operating system). Note - some 3.5" drives will also accept MF2HD 1.44mb high density discs (and use them as per 720k's), others will not. 

The 1st drive (the one the PCW is booted from) is drive A and any second drive is B. Where a hard disc has been added, the 1st partition is generally C (as on a PC). On single drive machines, addressing the drive as B is permissible as CP/M supports a means of identifying two discs which need to be swapped back and forth as being in drive A or B.

Note that whilst 3" 720k drives can read from (but not write to) 180k format discs, single density drives cannot read 720k discs so programs will report them as "not formatted or faulty".  

All the 3" and most of the 3.5" drives are belt driven - the Achilles Heel of the PCW. The drive belts - glorified rubber bands - perish with the passage of time and tend to set in one shape if not used for some time. "It worked when I put it up in the loft 5 years ago" is an oft heard boast, but more often than not it won't when subsequently retrieved and an attempt made to start it. Merely fitting a new belt is not the panacea for all ills claimed by many because rotational speed of the disc is crucial for correct reading & writing and the belt may well have failed because of partial or total seizure of the main bearing. The bearings were lubricated for five year life ... but in many cases that was 20 years ago! Moreover, fitting a new belt can destroy the head alignment. Alignment to the concentric disc tracks is equally important for successful operation; misalignment generally arising from worn sled motor bearings (the motor which moves the read head across the tracks) or physical damage arising from trying to load a damaged disc or withdrawing a disc before the motor has stopped turning.

1.2.2 - The Discs 

3.5" discs only fit into their drives one way up but 3" CF2's will fit either way because the same physical discs are designed to suit all PCW models. Care must therefore be taken as they may be used in two different ways:

  • Single density 180k format - PCW 8256 & 8512's 'A' drives - have just one read/write head so you have to turn the disc over to access the other side. By convention, these are called the 'A' and 'B' sides and each can hold 173k of data after formatting. The 40 tracks per side are numbered 0 to 39.

  • Double density 720k format - 9512 and 8512 'B' drives - not only pack double the data into the same space but also read BOTH sides at once so the capacity is four times as much - 720k (706k for data after formatting). Once a 3" disc has been formatted as double density,  the whole of the disc has been used so DO NOT turn it over in the hope of another 720k on the other side! If you do, you'll wipe the lot so make a habit of using the side marked 'A' (or '1') uppermost (9512)/to the left (8512) and mark the spine label accordingly by barring out the B or 2. The 160 tracks are numbered 0 to 159.

Some early manuals recommended using only of 'CF2DD' discs for the 720k Double Density format. Don't worry - any 'decent' CF2 should be able to be successfully DD formatted but, as with any disc formatting, it is wise to Verify the disc before use. 

However, beware relying on sub-standard discs! When the leading disc manufacturers ceased production of CF2's, a mass of horrid discs were imported from southern Europe and sold under a variety of names, including (wrongly & illegally) Amsoft. These are prone to sudden and complete failure and can be recognised by having criss-cross hatchings on the disc case and white write-protect levers in the leading edge of the disc (white showing through the two smaller holes when the disc is laid flat). Maxell discs are plain surfaced (no hatching) with red levers whilst proper genuine Amsoft ones are hatched but write protection is by a white slider tab on the rear left of the upper surface of the disc (so when laid flat, there's a hole showing white on the right but a rectangular slider tab on the left).

Whilst talking of write protection, it is worth noting that most program master discs were manufactured without write-permit tabs so their complete absence does not indicate a damaged disc.

1.3 Disc Format

180k discs have 40 tracks and 720k's have 160. Each track is divided into 8 sectors, the sector being the unit of transfer to/from the disc.

  • The first track of the disc - track 0 - is devoted to system information, notably the format type and number of tracks. On boot (start-up) discs this is followed by the boot program - the one which starts the snowball of intelligence gathering in motion by loading an embryo operating system and telling it to go looking for the next stage - the loading of an EMS program (or EMT on 3.5" models), eg CP/M or LocoScript.

  • Track 1 contains the all-important directory, or in 720k format, the first part of it. Each 32 character entry contains details of the name of the file, the group it is in, it's size and the location on the disc of the constituent parts of the file. As on PC's, the constituent parts may not be consecutive data 'blocks' - on well-used discs they may be scattered all over the (fragmented) disc. A single directory entry can only accommodate files up to 16k so, for files larger than this, 'continuation' entries are needed for each 16k of data. Each sector of the directory contains 16 entries so, if a disc read error occurs here, up to 16 files may be 'lost'. 

  • The rest of the disc is available for data storage and is addressed by means of a unique 'block' number. On 173k discs these blocks are 1k in size but on larger discs (720k and drive M) these are 2k in order to keep the block number within the permitted numerical range. This explains why files copied from 173k to 720k (or drive M) can apparently increase in size to the next even number of k and, conversely, files copied to 173k may appear to reduce in size. 

1.3.1 - Formatting Quirk - Upside down & mixed formats

It was stated above that turning a 720k disc upside down and formatting the B side in the hope of gaining a further 720k of space on the disc would result in loss of the initial formatting, and therefore all the data. This is not quite totally true. A 'naked' disc in fact has space for around 168 tracks, not 160, and due to the slight offset of the read/write heads, the first 8 tracks of the 'upside down' (B side) format will use space not used by the A side formatting and, by the same token, leave the last 8 tracks untouched. When turned back over to the A side, these untouched tracks are its tracks 0 to 7, which includes the directory. Hence, when inspected in (say) LocoScript, all the original files of the A side format will be listed and the attempt to gain a further 720k will appear to have been successful. Wrong! Any attempt to access any of the listed files will be met with "Disc Address Mark Missing" unless the whole file happens to reside within tracks 2-7. 

So do be careful when formatting - 

  • Don't be greedy by trying to get 1440k out of a 720k disc !

  • Smell a rat if a disc verifies perfectly up to track 7 then collapses in a heap with Disc Address Mark Missing on every single sector of Track 8 onwards.

  • The same formatting quirk applies when re-formatting a former 180k disc as 720k - the first 8 tracks of the B side won't be touched so loading it B side up will give the appearance that it is a 180k disc at the same time as the A side reports it as 720 !

  • Don't mix formats if you have confidential or sensitive info you want to get rid of because, if you do mix, some files from the previous format may still be readable.

  • If you have both 180k and 720k drives, always load discs of unknown type into the latter and, if apparently conflicting formatting info appears, use Disckit to determine which is the complete format. 

  • If the B drive of  your 8512 has given up the ghost but you are still soldiering on with just drive A, beware that 720k formatted discs loaded into drive A will report that they are "not formatted or faulty" so tempt you to overwrite potentially valuable data.

  • Don't rely on what the disc label says is on the disc !

 

1.4 - Drive M

Drive M (or simply M:) is the 'Memory Drive' - part of the PCW's RAM memory given over to acting just like a physical disc drive. Anyone who has ever tried copying a file from one disc to another on a single floppy drive PC will readily appreciate this PCW concept - just copy A to M, switch discs then copy back M to A.

Two other important facets of this are speed and flexibility. Speed because drive M works at electronic speeds rather than the mechanical speed of a revolving disc, flexibility because copying frequently used files or programs to M at the start of a session saves much disc swapping later on. Hence, when loading, Loco loads printer driver files, templates and the LocoSpell dictionary into M so that they are available whatever disc is loaded and, similarly, the standard CP/M start-up loads several useful programs into M. The downside of this that Start-up is prolonged and/or valuable working space is taken on M by files that are not required during the session.    

HEALTH WARNING

The contents of Drive M are lost when you switch off the computer or re-boot or there's a power cut  .... so always save valuable work on a physical disc as soon as practicable ! (this is not an idle warning - I have both the postcard and T-shirt to prove it!)

 

 

2 - LocoScript

2.1 - Introduction

LocoScript is the name of the word processing program that was bundled in the UK & Europe with the Amstrad PCW, but in the USA it was called LocaScript. A great many PCW users rarely if ever ventured beyond this program and now, over 20 years since its debut, it still has a faithful band of devotees, some of whom have recently gone back to it having failed to get to grips with the complexity of PC's or do are not physically able to master the use of a mouse.

2.1.1 - Loco Versions

LocoScript version 1.0 (the version number appears on the screen during booting) was bundled with the very first 8256's but, like most brand new software, it suffered from errors so was very quickly replaced by 1.1 and 1.2. Owners of at least 1.0 were offered a free upgrade to 1.2 but far from everyone took up the offer. Version 1.2 became the norm for subsequent 8256's and all the 8512's. Upgrades incorporating further refinements could be purchased, that to 1.4 to include LocoSpell being the most notable. 

Development was then switched to Loco 2 with its more refined use of the Disc Manager function keys and more comprehensive Layout features. Equally important was a new f2 Disc menu which offered disc copying, formatting and verifying from within Loco - previously it was necessary to re-boot into CP/M to perform these tasks then re-start into Loco again. Loco 1 users could purchase upgrades to 2 but the 9512, with it's noisy 'divorce material' daisy wheel printer, was bundled with Loco 2 from the outset (usually 2.12 or 2.16).

Version 2.28 witnessed a change in version numbering to even numbers for 8000 users and odd for 9512. More importantly, 2.28 saw the introduction for 8000 users of support for 'external' printers (driven via a CPS8256 serial/parallel interface) whilst version 2.29 also added support for the daisy wheel's auto sheet feeder ("ASF unit"), the least said about which the better. A 'Printer Support Pack' upgrade was also introduced at this time which, amongst other goodies, included drivers for a wide variety of dot matrix, inkjet and laser printers, some of which are still relevant to today's laser printers. Last known releases of Loco2 were 2.32 and 2.33, the 3.5" 9512+ optionally available with a Canon BJ10 bubble jet printer generally being shipped with a special derivative called 2.31b which included the necessary Canon printer driver. 

To maintain a presence at the budget end of the market, Amstrad introduced the 9256 with regurgitated 8000 series dot matrix printer. However, because it only had 256k memory, it was not best suited to the memory hungry Loco2, so was bundled with an adaptation of 1.4 from several years earlier which was called 1.5. The final genuine PCW, the 'all new' PCW10 was anything but this, being effectively a 9256 with 512k memory and, despite this additional memory, it was still bundled with 1.5

Meanwhile Locomotive Software, and their successors after they went into liquidation, continued development of the product with LocoScript 3 and then 4. Both of these used the same principal function keys as Loco2 but they offered significantly better font choice and quality; both ran to many versions and both were only ever available as paid-for upgrades as they were never bundled with any Amstrad product. It is interesting to note that 95% of all the 3" discs received for conversion to PC format were produced on the original 1.2 (8000 series) or 2.16 (9512). 

2.1.2 - Mixing LocoScript Versions 1, 2, 3 & 4

  • As with PC programs like Word, later (= higher numbered) versions of Loco can Edit (= Open) files from earlier versions but not vice versa (as the later format obviously wasn't thought of when the earlier was produced !).

  • Editing a doc from an earlier version automatically produces a file in the later format. You will probably be invited at the start of the edit to amend the doc set-up to utilise the more advanced features of the later version.

  • If you try to Print (rather than Edit) a file from an older version than the one you are currently using, you'll get "Not a Suitable Document".  You must first Edit it to produce a file in the current (later) version format.

  • If you try to open a doc from a later version than the current, you'll get a "Not a LocoScript Document" error. Converting to a later format is therefore effectively a one-way street, except in the case of Loco 4, which can back-convert to 3.

2.1.3 - LocoScript Manuals 

Apart from not having a 'what you see is what you get' screen display, one of the perceived failings of LocoScript was its manuals. The original version shipped with Loco 1 - intended to be a work of reference rather than a book to read at bedtime - wasn't at all bad but, very unfortunately, it was mercilessly hammered by the press. Having resorted to employing an expensive consultant, Locomotive's manuals for Loco 2 and subsequent upgrades went the opposite way - weighty tomes which were verbose & so repetitive that it was very easy to miss the important bits.

No apologies, then, for regurgitating some stuff that is probably in the manuals somewhere (if you can find it) ... and some things they don't want you to know about .....    

 

  • 2.2 - Using newly formatted discs

When you first insert a freshly formatted disc into LocoScript, the Disc Manager screen will report the disc as having 173k or 706k free, but there are NO columns for it in the lower (files) part of the screen. For brevity, the file columns only appear where there are some files in a Group so with no files in any Group of a new disc, no columns appear for the disc at all. With the ordinary cursor left & right keys thus unable to reach over to the disc, there seems to be no way of creating a file on or moving files to said empty disc. As it has probably been a long time since the last new disc was used, panic sets in.

Don't panic! Remember the Shift key !

The upper part of the Disc Manager's tabular screen shows a summary of the discs in the drive(s) and usage of the 8 "Groups" that are available within each. A cursor in the form of a reverse video block highlight shows the currently selected Group and it is moved with Shift+the cursor keys  

The lower part shows the files within the selected (highlighted) disc & Group and, if there's room, also in adjacent Groups. The cursor, again in the form of a reverse video highlight, shows the currently selected file and is moved with just the plain cursor keys.  

The two cursors move in tandem so, if you move the lower cursor left or right over a Group's bounding vertical line into the files for another Group, the upper cursor moves to the new current Group (which may be a fair distance if the intermediate Groups have no files in them). Similarly, if you use Shift+cursor keys to move the upper cursor, the lower file cursor scrolls across the screen to be positioned on a file in the newly selected Group. However, if there are no files in that Group, the file cursor transforms itself into two short vertical lines, one either side of the column boundary dividing the nearest used Groups. As such, it has often been accused of disappearing!    

The trick therefore is to use the SHIFT+Cursor keys to move the upper Group cursor to reach the Groups of the new disc. Once there, you can hit C to create a new file and, once it has been named and created, a column will magically open up for this Group and the new file be highlighted. Alternatively, when copying a file from another drive to the new disc, use Shift+Cursor keys when selecting the 'destination' of the new file. Once it has been copied, a new column will be created and the file cursor make a welcome return to its usual form.

2.2.1 - Tips

  • A good way of initialising a new disc is to select the Template.Std in Group 0 (System Group) of drive M, select Copy file (just f3 in Loco1 or f3 then Copy in Loco2/3/4) then hit SHIFT+Cursor Left until the highlight reaches Group 0 of the new disc then hit Enter twice. Once the file has been copied, the disc manager screen will refresh and a column for this group will magically appear!

Note: A 2k Template file copied from drive M to a standard 3" drive A of an 8256/8512 may report that it is now only 1k. Don't worry! Space on these drives is allocated in units of 1k whereas on M and all high density drives, the unit is 2k. Hence the reverse can happen when copying from A to M (or A to B) as file sizes here are rounded up to an even number. 

  • Use this Shift+Cursor key method to create files in or copy files to a previously unused Group on a disc. To name a Group, it's f5 then Rename Group in Loco1 or just f4 in Loco2/3/4.

 

  • 2.3 - Group Philosophy .... and Templates

Modern computers allow discs to be divided into an almost limitless number of directories (or 'folders' in Bill Gates' Speak) and for there to be sub-directories (sub-folders) within these so as to simulate the drawers and dividers of a manual filing cabinet. LocoScript calls it's disc divisions 'Groups' and there is a fixed maximum of 8 for active files (plus another 8 for Limbos - see below) but there are no facilities for sub-groups. On a new blank data disc, the Groups will be called Group.0 through to Group.7 but they can be given names like Letters or Fred so that their contents can be more easily recognised. 

Like Baldrick, Locomotive Software had a cunning plan. This was to keep all files of one particular type of document layout  - eg letters, manuscripts or mailing labels - together in one place (= in one Group). By having a 'master' layout file (called Template.std) in each Group which is automatically opened in response to the 'Create' new document command, creating documents to a uniform layout is very easy. Moreover, because the Template.Std is merely an ordinary Loco document, it can contain fixed text such as one's address and phone number to save entering it each time. Automatically copying the template and simply asking for a name for the result is thus a much better way for new users to 'get going' than the alternatives of starting with a totally blank page or having to select a particular template file from somewhere then copy it, give it a new name and then edit the result. 

Hence the Groups on the Loco program disc which contain sample templates are named to reflect their layout type eg Letters, Labels etc. All Group names and Template.Std files are copied to drive M (the Memory drive) during the start-up ('booting') process so that they are available for use during the session.

So far so good, but not everyone wants to keep their documents organised in that way. Authors and suppliers of professional services may want to keep all documents relating to a particular novel, project or customer in one place, irrespective of whether they are letters, invoices, notes, minutes or threats of legal action. A common solution here is to f3 copy a suitable previous document (possibly from another Group or even Disc), give it a new name and delete any unwanted text, but this can be a bit slow going each time if there are several pages to delete.

A refinement of this technique is to delete this unwanted text just once and call the result by a meaningful name eg Template.Let, .A5, .Inv etc so that there are several  different layouts available within the Group. To then create (say) a new invoice, f3 copy Template.Inv as Invoice.B07 then edit in the new text. 

The same technique can be used to update an ordinary Template.Std if you move house or have honed a particular document's format to perfection with multiple layouts, tabs and other fancy page settings. Rather than then trying to re-enact all these changes again on the Template.Std so that all newly created documents will inherit these refinements, delete the existing Template.Std, f3 copy the honed document as Template.Std then edit it to remove all unwanted text so as to leave just the bare bones. 

NOTE - Making alterations to a Template.Std does NOT affect any existing documents that were created using it. As described above, new documents are created by making a copy of the then existing template so will reflect its contents at that time and there is no mechanism for 'retro applying' subsequent changes to it. This can be a pain if you only discover a better layout when you have reached chapter 30 of a book, but it does mean that old letters written before you moved house don't suddenly change to your new address ! 

 

  • 2.4 - "Limbo" Files & Disc Manager's "Free Space" Display

When you erase a file, it is not completely removed from the disc as you might imagine. Instead it simply has 8 added to its Group number in its disc Directory entry to put it into the Limbo range of Group numbers - 8 to 15. In other words, the Limbo system is a mid 1980's forerunner of the "Recycle Bin" that was only introduced on PC's in Windows 95. Similarly, when you finish editing a file and write the new version to the disc, the previous version (the one you selected to Edit ie the 'input' to the edit) is retained as a back-up by having 8 added to its Group number to put it into the corresponding Limbo group.  

Limbo is thus a valuable 'safety valve' when problems arise - it enables you to retrieve accidentally deleted files or go back to the previous version if a problem arises with the latest edit. However, whereas CP/M treats all 16 Groups (or Users as it calls them) equally, LocoScript only recognises the first 8 groups (0 to 7) as containing 'active' files. This means that the Disc Manager Screen's display of space used on a disc only shows that taken by 'active' files so the odd situation can arise whereby Loco reports a disc as half full but CP/M will say it's full if you try to copy anything to it !

More importantly, when Loco is looking around to find space on the disc to save a file upon completion of an edit, it will randomly delete Limbos if there's insufficient free space available until enough is. Hence, other than by limiting your use of discs for 'active' files to less than half of the nominal capacity of the disc, you cannot control the deletion of Limbo files ... and Murphy's Law dictates that, when a problem does arise, the one you want has gone!

2.4.1 - Tips

  • The Disc Manager Screen at start-up shows the number of Limbo files in each Group but not what they are. To show Limbo files, hit f8 Options and put a tick (with the Option Set [+] key) against Show Limbo Files.

  • To "recover" a Limbo file to make it active again, show Limbo files as above, select the file with your cursor, hit f4 (Loco1) or f3 File (Loco 2/3/4) and select Recover from Limbo. If an active file of the same name already exists in this Group, you must amend the name to make it unique.

  • Recovering a file from Limbo does not take up any more actual disc space even though Loco will afterwards report that more is then used. In fact the file is left untouched because all that happens is that 8 is subtracted from the Group number in the file's directory entry so that Loco now recognises it as an Active file (and therefore now takes into account the space it occupies).

  • The only actions allowed on Limbo files are Recover and Delete. If you need to copy a Limbo without first 'recovering' it, use PIP in CP/M.

 

  • 2.5 - Finish Edit versus Abandon Edit

When you Finish an Edit of an existing file, before your masterpiece is written to the disc, firstly any existing Limbo version of the file on the disc is erased and the input to the current edit is re-named to become the new Limbo file. Next, if there's insufficient free space on the disc for the new file, other Limbo files are erased then, finally, the new file is written.

If you haven't actually made any alterations to the file eg you just hit Edit to have a look at its contents, this causes unnecessary disc activity, particularly in the disc directory, as well as possible loss of Limbo versions of other files on the disc .... so choose Abandon Edit instead to leave the disc as was. Obviously, if you have made alterations which you want to retain, don't hit Abandon ! 

 

  • 2.6 - LocoScript Bug which can cause extensive data loss

As described above, a considerable amount of disc activity occurs every time you Finish an edit. Unfortunately, there's a bug in all versions of LocoScript which can cause significant loss of data during this process. Primarily it occurs on 720k discs containing lots of files (100+) and/or which are very full - so multiple Limbos have to be erased to make way for the new file - but it can also occur on 8256/8512 180k discs with files that are large. 

Somehow Loco forgets where it's at during the process and it either re-writes an updated directory block (= 16 file entries) in the wrong place in the directory or completely fills a whole directory block with zeros. Apart from suddenly losing a number of files from the file list, common symptoms are "Unexpected End of File" errors when moving through a file during editing, the Disc Manager Screen showing files twice or showing one or more 'files' with no name and occupying 0k.

2.6.1 - Advice:

  • If a disc behaves as described as above, do NOT write any more files to it as you may only worsen the situation. Copy all the files you can to a new disc. Although CP/M's PIP is a much quicker way of bulk copying files, it will collapse in a heap if it encounters an all-zero directory block whereas LocoScript has been trained to plough on over the duff bit and access those entries beyond.

  • Remember that the Disc Manager Screen's figure of used disc space excludes Limbo files so once you have edited each chapter of your masterpiece at least once, the actual space used will be around double that indicated. Discs are cheap and still readily available whereas it could take a very long time to re-enter lost data ... and that's assuming you have a hard copy to fall back upon (!) .... so stop using a disc once it has reached just under the half-full mark. In this way you should have a Limbo of each file to fall back on should the worst happen and a Data Error or Missing Address Mark afflict any file.

  • The Disc Manager Screen can show you Limbos as well as Active files - hit f8 Options, cursor as necessary to Show Limbo Files then hit the Option Set Key [+] to put a tick beside it then Enter.

 

  • 2.7 Using copies of system 'Start of Day' discs v blank discs for data

Although the majority of discs received for conversion to PC are pure data discs, a significant number transpire to be copies of the supplied Loco Program disc or the 'Start of Day' copy made of it. With the 180k format of the 8256 and 8512, the Loco program components take up most of the disc so there's precious little available for saving ones own work even after deleting the supplied samples and irrelevant templates. And, as discussed above, there are all the attendant dangers of working with very full discs. Even on the 720k species, the later versions of Loco take a brave chunk of space so why is that when users need to use a new disc they copy the program disc rather than using a blank data disc ?? 

Suggestions that have been put forward include ...

  • Users are unaware that discs can be changed during a session so switch off and re-start each time they want to access a different disc. To tell Loco that you have changed discs, hit the f1 key in Loco 1 or f7 in later versions. (f1/f7 are listed as 'Disc Change' at the top of the Disc Manager Screen).

  • The program disc must be in the machine at all times during a session. No ! All programs and system files (eg templates, dictionaries and printer drivers) needed for a session are copied at start-up to drive M - this is why it takes so long to boot ! (and why it's better to use Disckit for copying discs than Loco2/3/4)

  • "I've tried to use a blank disc but just can't get my cursor over to it to use it" - see "Using newly formatted discs" above !!

  • "I have saved all my Template.Std's on my Start of Day (SoD) Disc so it's a good way of copying them all to a new disc". Yes, but all such templates are automatically copied to Drive M at start up and when you create a new document, if there is no Template.Std in the current Group, Loco looks for one in the corresponding Group on drive M (Note though that when there are discs are in both drives of a twin drive PCW, the search for a suitable template is more complex so it is best to start each newly used Group on a disc with a copy of the relevant template).

  • "I have saved several useful files on my SoD, including some templates which are not called Template.Std, so copying the whole disc is quicker than laboriously copying all these to a new blank disc." Agreed but, especially on an 8256 or 8512, why not then delete all the program files? Hit f8 Options and tick (with the [+] option set key) both the Show Limbo and Show Hidden files options. With the program files now visible, delete them and once all in Limbo, delete those too. Ditto any LocoSpell dictionaries and unnecessary sample files.

  • "I'm a bit disorganised so at least I know that I can start the PCW from any old disc I come across". There's no answer to that!    

 

3 - CP/M

3.1 Introduction

This is the name of the operating system supplied with the Amstrad PCW - the software which enables the PCW to read and write things to disc as well as service other bits hung on to the computer such as printers. CP/M thereby enables the PCW to operate as a conventional computer (or at least one of the 1980's) and so set it apart from other dedicated word processors. A wide range of software soon became available for the PCW, ranging from accounts to payrolls, databases to desk top publishers, spreadsheets to family tree makers ... and some games. One could even write one's own programs using the supplied Mallard version of the Basic programming language developed by Locomotive Software.

Over the years, its slowness and restricted capacity have meant that most users of the PCW as a pure computer have migrated to PC's or Macs but it still has a useful role to play in this mode, if nothing else, to support its prime use for word processing using LocoScript. A couple of the programs which do this are covered below - PIP and Disckit.

 

3.2 - To Start the PCW in CP/M

Start the PCW in 'computer mode' by switching on, inserting the CP/M system disc and waiting until the "A prompt" (A>) appears. On the 9512, this will take a few moments because a few 'helpful' preparatory commands are obeyed during start up. To stop this happening (as is desirable when DiscKit is to be used for disc copying), hit the Stop key a couple of times as soon as the 'CP/M version' legend appears at the top of the screen. 

The A in the A> 'prompt' means that unless you specify otherwise, any command to load a file or program will first be directed towards (or "default" to) the A drive and > is a prompt to indicate that it is waiting for you to type in something ('enter a command'). Just as with DOS on PC's, this may be entered in upper or lower case - it matters not - and all commands at this prompt must be followed by either Enter or Return to signify the end of the command (these two keys being synonymous in CP/M, unlike LocoScript).

3.2.1 - Addressing the drives

If you now type in just DIR[Return] you will get a DIRectory list of the files on drive A because, without any explicit instruction to do otherwise, it operates on the "default" drive as shown by the prompt. To switch the 'default' drive from A to M, simply type M:[Return] and the prompt will change to M>. Now repeat the DIR and a different list - those on M - will appear. To obtain a list for a drive other than the default, you have to be explicit so, with the default now as M, to obtain a list for drive A, the command becomes DIR A:[Return]. Note the space between the Command (DIR) and its 'parameters' (ie A:) and that a colon is the computer shorthand for 'drive'. As with DOS, you must enter the colon when referring to drives - otherwise it will think you are talking about a file called A or M - but, unlike DOS, the colon does not appear in the prompt (ie just A> rather than A:>).

NOTE - The second drive on a twin drive PCW is addressed as drive B so, to obtain a directory listing of a disc in that drive, type in DIR B:[Return]. Note that if you do this on a single drive PCW, you will be invited to "load the disc for Drive B". This does NOT mean that you do have a second drive hidden in the bowels of the machine somewhere (!), it merely allows sequential access to two different discs in the same drive so uses A & B 'drives' as a way of keeping track of them both.

 

3.2.2 - Switching Discs

Unlike Loco, there is no key to hit to tell CP/M that you have switched discs in a drive. In theory at least, it should sense a disc change so, the first time a new disc is accessed, you should hear the characteristic 'bomp bomp' sound of the directory being read. However, this does not always seem to happen and because the disc directory is copied to memory to speed access, a DIR command can list the contents of the previous rather than current disc. A tad confusing! Repeating the command and/or re-setting the disc usually restores the knickers to a less twisted state. 

NOTE - When switching between single density (180k) and double density (720k) discs in a 720k drive (like the B drive of an 8512), you may well be treated to 'Disc Address Mark Missing' for track 1 (the directory track) so be fooled into believing that the disc is faulty. Perseverance with a mixture of R to Re-try, I to Ignore and re-setting the disc usually does the trick.

 

3.2.3 - Commands

Just about everything you type in at the A> prompt will be a command to load & run a program of that name, programs being recognised by having .COM as the last part of their name (the 'file extension'). Hence entering PIP[Return] is a command to load Pip.Com from the default drive then run it, so it follows that the program file of the specified name should be available on the disc in that drive. However, prefacing the command with the drive letter enables you to load the program from a different drive without having to disturb the current default drive eg M:PIP loads and runs the program from drive M without affecting the default drive or the disc thatís in it. Part of the 9512's CP/M start-up process is to run PIP to copy itself plus a couple of other useful programs from A to M. This enables you to run PIP with M:PIP at any time during the session without having to switch discs in A to the one with that program on it - very useful !

 

3.2.4 - Users = Groups  

CP/M supports up to 16 Groups - or "Users" as they are usually referred to in CP/M lingo. These are numbered from 0 to 15 but, unlike LocoScript, the vast majority of CP/M software only ever uses User 0 for its files. This is the 'default' user so 0 does not need to be specified as a qualifier to the drive letter in commands except on very rare occasions which need not bother us here. However, different Users do come into play when dealing with LocoScript discs in programs like PIP (see below) and the references to them must be by their Group number and not any name they have been called in Loco. This can easily be worked out from Loco's Disc Manager Screen as Groups 0-3 are down the left hand column of the drive summary and 4-7 down the right.    

 

3.2.5 - Running programs from drive M - getting a Full Directory Listing

To obtain a list on screen of all the files - including Limbos - on a disc in drive A (rather than just Group 0 as was done above), enter the command:

M:DIR A:[users=all]      then hit the Return key    

Note that the M: has been specified this time. This is for two reasons:

  • DIR is one of four commands which, in their simplest form, can be handled by CP/M without recourse to running the named program. These are called 'built-in' commands so typing in just DIR or DIR M: as was done at the start did not actually need the program disc in the drive at the time. However, as soon as anything complicated is entered, like stuff in square brackets, the full program needs to be loaded and run.

  • By running programs from drive M, disc swapping is minimised and, on single drive PCW's, makes things possible that otherwise would not be eg a full directory listing for any disc which didn't have Dir.Com on it!  

 

 

  • 3.3 - Using the Disckit program to Copy, Format & Verify discs

Please click here to transfer to the page dedicated to Disckit

 

  • 3.4 - Using PIP to copy multiple files

PIP can be run in two ways:

  • By entering PIP at the command prompt followed by a space then details of the files(s) to be copied in one hit eg PIP M:=A:PIP.COM.

  • Just PIP to perform several different tasks in one 'run' of the program. The prompt changes to an asterisk to denote that one of PIP's commands must now be entered. When successfully completed, another asterisk prompt will appear. To terminate the run and return to the normal CP/M command prompt, just hit the Return key. 

The latter is recommended and assumed here .... so just type in PIP to get started. 

Pip's command syntax is the opposite to the DOS copy command so does take a little getting used to. It takes the form: 

make the Destination(s) = to the Source(s)

so   M:=A:PIP.COM will copy the PIP program from drive A to drive M. 

PIP's syntax supports the ? (any single character) and * (any number of characters) 'wild cards' so 

M:=A:*.* will copy all files on drive A to M
M:=A:*.COM will copy A to M only those ending in .COM
M:=A:A*.* will copy A to M only those starting with the letter A

This is all very well but it only addresses User 0. What about the others, which may well arise when dealing with discs from Locoscript? This is where the [Gn] parameter comes in, the n representing the Group number.

M:[G1]=A:[G7]*.* will copy all files from Group 7 of A to 1 of M

so is very useful when reorganising discs, especially when a disc is getting full and you want to peel off a complete Group on to another disc without the tedium of individual file copying in Loco. Another useful variant is:

B:[G1]=A:[G9]*.* will copy all files from (Limbo) Group 9 of A to (the corresponding Active) Group 1 on drive B

To quit the program and return to CP/M's command prompt after the last copy, simply hit the Return key. 

Tips

  • When doing a series of PIP's to reorganise discs, it's a good idea to script out on paper your planned sequence of operation beforehand. 

  • The Paste key summons back the previous command you typed. You can either just hit Return to repeat the same action or amend it before so doing - this saves a lot of typing when doing a series of basically similar operations.

Have fun !

 


If you have any comments or tips of your own, please e-mail to

malc@luxsoft.demon.co.uk


 

LuxSoft of swinging downtown Luxulyan

 "Clinging to the Trailing Edge of Technology"

email malc@luxsoft.demon.co.uk

Established 1986 - This page last amended 7th May 2014

All text strictly Copyright LuxSoft of Luxulyan 2000-2014. No part of this write-up may be copied, pinched or otherwise plagiarised without the express permission of the author.