Back to index

Info for pcw8256


====== Amstrad PCW8256/8512/9512/9512+/10 ======




===== Features =====

* CPU: Zilog Z80A (The CPU is running at 4 MHz, but is slowed down by the internal clock to 3,4 MHz) [PCW8xxx]; Zilog Z80A 4 MHz [PCW9xxx]
* Co-Processors: Amstrad ASIC custom chip (Video), NEC 765 (DD controller) [PCW8xxx only]
* RAM: 256 KB (16 banks of 16 kb each) [PCW8xxx]; 512 KB [PCW9xxx]
* ROM: 48 kb [PCW8xxx]; No ROM chip: Bootstrap loader is masked onto a custom chip [PCW9xxx]
* Text Modes: 90 x 32 [PCW8xxx]; 90 xchars. x 35 lines [PCW9xxx]
* Graphic Modes: 720 x 256 (PAL), 720 x 200 (NTSC) [PCW8xxx]; 720 x 256 dots [PCW9xxx]
* Colors: Monochrome (black & green) [PCW8xxx]; monochrome (black & white) [PCW9xxx]
* Sound: Beeper, 1 channel
* I/O Ports: Z80 Bus, Parallel
* Keyboard: Mechanical keyboard with numeric keypad end special edit keys (COPY,CUT,PASTE,PRINT,etc.), 8 function keys [PCW8xxx]; Full-stroke 82 key with function keys, numeric keypad and special editing keys (COPY, CUT, PASTE, PRINT,etc.) [PCW9xxx]
* Built In Media: 1 Hitachi 3" disk-drive (160 kb/side) [PCW8xxx]; 1 Hitachi 3" disk-drive (720k) [PCW9xxx]
* OS: CP/M, CP/M+
* Built In Language: Mallard Basic [PCW8xxx only]
* Peripherals: Printer, parallel/Centronics interface [PCW8xxx]; Printer, RAM an serial expansion units [PCW9xxx]



===== Usage =====

These Systems Require a Boot Disk to Run!



===== Known Issues =====

Notice that these systems are TESTDRIVERs, i.e. they're not included in the pre-compiled MESS you find at mess.org -- http://www.mess.org/



===== History and Trivia =====

The Amstrad PCW 8256 was a dedicated word processing computer (PCW stands for Personal Computer Wordprocessor). It was supplied with everything necessary, the word processor, printer and dedicated keyboard (with Cut, Copy, Paste and Print keys). This model had great success because it was the first word-processing system available for such a low price. Once again Amstrad used the same principles with this professional computer as it did with the CPC-464 on the home-computer market. Two years later, 700 000 PCW systems had been sold!

All the hardware was located in the monitor case, as well as the 3" floppy disk drive. An optional secondary disk drive could be added (360 kb/side). There was only one power cord used for the printer, monitor and keyboard - it couldn't be simpler.

The printer was an Amstrad matrix printer (90 cps in draft mode and 20 cps in letter-quality mode), but it was not possible to connect another printer to the PCW. To use another printer, optional RS232 or Centronics interfaces were available.

The system was supplied with a word processor (on disk) developed by Locomotive Software (the company who made the BASIC language for the Amstrad CPC series) called LocoScript. Dr. Logo and a Basic called Mallard Basic were also delivered on disks (fun fact: Mallard is the name of an old train engine). This Basic was powerful and offered a lot of file-management capabilities. The Amstrad PCW-8256 was also delivered with CP/M+.

Locoscript was powerful but somewhat austere. You had to read 700 pages of documentation in order to master it. It used 154 Kb RAM, and the remaining 102 Kb could be used as a virtual disk. Each floppy disk, called a volume, could be divided in up to 8 sub-volumes. A particular page layout could be assigned to each of these sub-volumes. The system displayed text in an odd but useful 90 x 32 resolution. Of course as it was text-based software, you could not see exactly what would be printed (no WYSIWYG here). Another drawback was that it was not possible to link a document with an address book or a database, to generate multiple documents (this was to be corrected with LocoMail, LocoFile and LocoScript 2 a few years later). The 320k disks stored up to 90 pages of 2000 characters.

In Germany, the PCW series was called Joyce.

Another PCW model was launched a few months later: the Amstrad PCW 8512. It has the same characteristics apart from having 512 Kb RAM to handle bigger documents, and two 3" floppy disk drives. The top one is a single-sided, 40-track (180 Kbyte) drive, the bottom is a
double-sided, 80-track (720 Kbyte) drive. 40-track disks could be read in the 80-track drive, but it's not advisable to write to them there because the 80-track drive has a narrower head. It had slightly darker plastic mouldings than the PCW-8256, grey instead of white.

It was followed by the Amstrad PCW 9512, which had the same basic characteristics. However, it corrected two of the main criticisms of the 8512: the low quality of the printer and the machine's non-business-like styling.

It had a paper-white monochrome screen (black on white) unlike the 8512, which had a green monochrome screen (green on black). It was equiped with a 3" 720k floppy disk drive (a second one could be added) and used a daisywheel printer instead of the dot matrix printer of the PCW 8256/8512.

Like the previous models, it could run CP/M+ and was supplied with the Locoscript V2 word processor including LocoSpell and LocoMail, and Mallard Basic, both made by Locomotive software. DR Logo was also supplied as standard.

In 1991, two new models were produced:
* a cut-down model called the PcW 9256 (same characteristics, but only 256 KB RAM and a 3.5" disk-drive) which was a replacement in the PCW range for the PCW-8256;
* the PcW-9512+ which replaced the PCW-9512. It was almost the same machine but with a 3.5" 720K drive.

Finally in 1993, these models were replaced with the PcW-10.

//(info from old-computers.com)//

These machines were designed primarily for word processing (hence the name "Personal Computer Word processor"), but are capable of a lot more.

The original PCW8256 system had a green screen monitor, with 2 3" disc drives mounted vertically in it, a keyboard and a special printer. (The CPU and other hardware was also contained in the base of the monitor)

Later models changed the case design, but also allowed the use of any printer that was available. (The original 8256 had a proprietary printer and interface).

The hardware is simple, a Z80 running at 4MHz, slowed to 3.3 with wait states, an Amstrad ASIC custom chip for driving the display (2 colours, 720x256 in PAL, 720x200 in NTSC), a beep for sound, and a NEC765 floppy disc controller.

The boot-program is contained on the printer chip, and is enabled at power-on or reset. The data is passed through a Amstrad custom ASIC chip, and is executed by the Z80. The program is simple, and just loads track 0, side 0,sector &01 to &f000 where it is then
executed at &f010. (The first 16 bytes appear to contain some format parameters which are used to initialize CPM). I don't own a PCW machine so I don't know the exact display that the PCW shows on boot-up.

AFAIK, no dumps are available for this program. The MESS driver uses a program coded by myself. This program waits for a key to be pressed and then starts the boot procedure. If an error occurs, the screen will flash 6 times, and then it will repeat the procedure. If
all is well, you will see some lines appear on the screen, and the boot will continue.

The original computer came with CP/M and Locoscript (a special word processor).

Since it was able to use CP/M there was a lot of public domain and CP/M programs available that would run on it.

A few games were written for it, two of these are "Head Over Heels" and "Hitchhikers Guide to the Galaxy".

//(info from Kevin Thacker, author of MESS driver)//



===== Links =====

* Ian Macdonald's PCW pages -- http://www.caliban.org/PCW.html
* PCW at old-computers.com -- http://old-computers.com/museum/computer.asp?c=189



===== Other Emulators =====

* Joyce -- http://www.seasip.demon.co.uk/Unix/Joyce/index.html




Generated on Sun Jul 19 10:17:28 2009