A little history…

Amstrad CPC is a machine 8 bits based on Z80 with 4MHz. The first of the range was the CPC464 in 1984, equipped with a cassette player integrated it was placed in conccurent of Commodore C64 much more complicated to use and expensive. It was a real success and left this same years the CPC664 equipped with an integrated diskette drive 3". Its life was of short duration since in 1985 it was replaced by the CPC6128 which more compact, was looked after more and especially which had 128Ko RAM instead of 64Ko. The CPC6128 completely swept Commodore C128 and the MSX which never succeeded in being essential in France. Moreover, just like the PC, the CPC were frabriqué under various marks; for example, in Germany, one spoke about Schneider CPC.

They were thus the beautiful days to the output of Atari ST520 in 1986 then of Amiga A500 in 1987. In spite of these two machines largely more powerful Amstrad succeeded in being maintained thanks to their low cost and to their good ergonomics. In 1990 Amtrad decides renouveller its range and leaves 464more and 6128 more compatible with their new console, the GX4000. These machines had really success only in France but did not survive, in 1992, at the output of Amiga A1200 and the fall of the price of the PC (moreover initiated by the Amstrad company itself.). The last French editors gave up the CPC in 1993 and the last French review, Amstrad Hundred percent, put the key under the gate at the end of 1993.

Nevertheless the machine it did not die for as much and the development never ceased since 1984!

Architecture…

Amstrad CPC is a small electronic jewel! Not how its architecture is a revolutionist as could be to it that of Amiga A1000 in 1985 but because it is stuffed easy ways! The ingeniousness of implementation of the various components does certainly of Amstrad one of the best machines 8 bits if not the best.

Video side it has multiple video modes and all is skeletal. There are a mode low resolution (ratio 160x200) 17 colors, an average mode resolution (ratio 320x200) 5 colors and a mode high resolution (ration 640x200, single in 1984!) 3 colors. The pallet consists of 27 colors RVB. There exists moreover one interlaced mode which makes it possible to display without stumbling of the 800x600 and the video chipset allows bibouiller to do it 27 colors instead of 3. It is also possible to sweep in STAKE mode, NTSC or even VESA! The video RAM can go until 64Ko and it is allowed to make scrollings hardware horizontal and vertical, undulations of screen hardware, etc…

Side RAM and ROM the machine has a MMU (Gate Array) relatively flexible which makes it possible to manage until 512Ko RAM and 4Mo of ROM whereas Z80 can address only 64Ko of it. A whole heap of commutation is possible: it is for example common to commutate a ROM in reading and a RAM in writing and this with the same address what is very useful for the video RAM. Moreover, the gate was left open as for possible evolutions what allows customiser a CPC to plusior Mo of RAM without concern.

Side the its CPC has same chip that Atari ST It is certainly definitely less powerful than processor SID of C64 but exploited well it gives honourable results. It offers 3 channels FM with volume, frequency and level of white vibration adjustable. It also has a generator of envelopes of hardware volume and makes it possible to play of the samples according to a logarithmic scale 4 bits.

The Operating system

The CPC is upon the departure a machine multiOS since it has 2 OS. The first, entirely in ROM, was developed by Locomotive Software and is without question one of best existing OS on machines 8 bits (it does not have great a deal to even envy OS of Atari ST). The basic interface by defect to exploit this OS is a BASIC, the Engine BASIC. It is relatively powerful and fast but there is a whole heap of other graphic interfaces or not. But the most interesting point of this OS is its system of ROMs; indeed, by the addition of ROMs in cases of external extension one can simply increase the functions of the system without deteriorating the RAM Of many programs are available besides as much in version disk that in version ROM; thus, as of the demarrage, have has for example of a word processing or a assembor without to have had to make any loading: it is faster than a hard disk!

The second OS is only partially in ROM, it is the CP/M from DIGITAL Research (the trick which Microsoft copied to make its MS-DOS). It is a OS reserved of professional use which makes it possible to use all the software planned for CP/M 8 bits on CPC with knowing DBASE, Multiplan, the Turbo Pascal, the Language C, etc…

In fact the CPC is the machine 8 bits profiting from best OS!

And the CPC+ then?

It is an improved CPC. It has 16 sprites hardware zoomable 15 colors with management of the transparency, a pallet of 4096 instead of 27, 3 channels DMA for the management of the sound (what makes it possible to play of the music FM, the samples and to even emulate sounds SID of C64 without occupying the processor), of various facilities for the management of the scrollings hardware, the interruptions, etc… In fact, it is a good machine; one can even affirm that it is about the most powerful machine 8 bits ever conceived, but it left too much late. Whereas there are thousands of programs for CPC he has of them there only a few tens for the CPC+; fortunately it is 99% compatible CPC. The large difficulty comes from the OS which did not evolve/move since the CPC6128 and which does not manage absolutely these new functionalities. But the machine recently is finally recognized by the scene and this adoption will make arrive a whole heap of new programs.

Our computer equipement of use…

With the rédac' we have a standard CPC6128 1 equipped with a reader 3"1/2, of Multiface II+, Romboard (case of extension ROM), of a mouse AMX, a video digitizer Vidi-cpc, and a printer Canon BJ200ex. It is about our principal computer which is used mainly for the DTP of Quasar CPC and like machine of software development.
Its right arm is a standard CPC664 2 equipped with a reader FD1 and a scanner DART coupled to a printer DMP2160; it is used exclusively for digitalization of the images then used in illustration in Quasar CPC.
For some time now, these good old men CPC found company in the presence of a standard CPC6128 4 assembled out of turn thanks to Cpc-isa Card de Siou (cf Quasar CPC 17). This CPC custom is equipped with Ramcard and a reader 3"1/2, but especially, on Cpc-isa Card, of SoundBlaster Pro2 and a Multi-IO card with reader 3"1/2 HD, Cd-rom reader, mouse PC and very very soon modem and hard disk. It is useful primarily for our various software and hardware tests.

Offset has one 6128plus with reader 3"1/2, Multiface II+, mouse AMX and Ramcard (case of emulation of ROMs of extension); it is our principal computer of development. With dimensioned, there are also Amiga A1200/030 (for the play) and Amiga A1200/060 (for the Internet).

Zik has as for him one 6128plus with reader 3"1/2, Romcard (also a good configuration of development) but also Amiga A4000/040 (for the Internet) and a PC (for the electronic design of the cards).

Tony, bursts himself with 1 standard CPC6128 0, one 6128plus, one reader 3"1/2 and Multiface II+, as well as Amiga A1200/030.

SNN is the happy owner of one 6128plus with reader 3"1/2 and of a PC.