Amstrad CPC

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Amstrad Colour Personal Computer is a computer made by Amstrad in 1984. It was made to compete with the ZX Spectrum and the Commodore 64 but unlike those computers, it was bundled with a monitor either colour or green and a built in tape/disk drive. While it was a 3rd place machine in the UK but was not a failure, it did surprisingly well in France and Spain with the latter still has a fanbase creating games.

There are several models of the computer:

The original model 464 and the 664 with the difference between the two is whether one used cassette tapes (464) or disks (664).
672 was a machine made to fool the Spanish government at the time with an extra 8k of memory that does not work. It was due to an unfair computer tax where machines 64k or less had to be taxed if they were not Spanish made.
6128 has 128kb of memory. Many games either require this or use the extra memory to provide music or extra features in the game, they might also load faster.
CPC+ where there was a redesign to resemble the Amiga with a higher colour palette of 4096 colours, hardware sprites and support for DMA sound that only one game supported (Prehistorik 2). They also have a cartridge port as well. A very few games use the extra features of the computer and most of the time it was the extra palette.

As well as computers, there is also a console version based off the CPC+ called the GX-4000 that is technically slower. It was one of the most failed consoles in gaming history; it couldn't compete with the Master System, the games were too expensive with a very few exclusives or differences compared to the regular CPC version and the power supplies caused fires. It was discontinued shortly after launch.

Usage

It is highly recommended to use disc files that end with .dsk rather than tapes because they are easier to set up and boot up much faster in seconds than minutes. Tapes are a lot harder to set up and it emulates the long loading time too, for most cases if there is a tape only game someone made a disc version of a game usually considered to be a cracked version. There are some exceptions such as Dinamic's Professional Tennis Simulator in English (Simulador de Profesional Tenis does have a disc version though) and Motos. Some Spanish release versions of games do not have the copy protection that is on the UK version but still are in English and are more compatible, just in case it fails on an emulator. If there's no Spanish release, you can use a cracked version of the game. Many also include trainers that are handy for tough to beat games or want to rip easier. You can also use cartridges as well if it is a cart only game or want to rip a CPC+/GX-4000 version of a game.

Remember to boot up a game, you type run"(game name listed on the file), run"disc or run"disk. If you're not sure what to type in for the game name, type cat where it displays the file or files on the disc. The one ends with .bas is usually the one to go to but you don't type the .bas in. If it goes strange, reset the emulator because sometimes you have to type |CPM instead since they used it for copy protection or a different way for bootup.

Ripping Tools

WinApe

TODO: Picture of the Tile viewer.

First of all change the ROM settings, go into Settings then to Memory. Change Upper 7 to Empty, this will use the CPC+ cartridge that is also bundled with Burnin' Rubber. The default ParaDOS has a lower compatibility than the official Amstrad ROMs causing some games to not boot up at all even with discs in. Meaning that it goes from sketchy compatibility to running most of the library apart from some early Basic 1.0 games that often got 1.1 versions and some others. Just remember to press the Function 1 button (1 with num lock on full size keyboards, have to be changed on modern laptops) otherwise Burnin' Rubber will start.

After set up go to Debug and then Pause, this will display the debugger to pause the game. Then go to Find Graphics.

(picture of Tile Viewer)

Very rarely the tile viewer detects the wrong screen mode so it has to be changed but usually gets it right with the Current option. On the Amstrad CPC, there are 3 screen modes with a 4th being a hardware side effect that no game used. Most games use Mode 0 or Mode 1. Mode 0 supports 16 colours but has a lower resolution meaning that sprites can be blocky. It is sort of comparable to a Master System. Mode 1 has a higher resolution however only has 4 colours to choose from like the NES but for the entire screen rather than just a character. It was often used for Spectrum ports or games that were ported to the Spectrum however some games used it for an advantage and is easier to create a cartoon/detailed look for the sprites. Very few games such as Amstetris use Mode 2 since only two colours can be used, it is usually used in programs/utilities and text adventures.

The CPC+ and GX-4000 games also have another display mode and those are hardware sprites. Not many games support this however it is used in Dick Tracy, Epyx World of Sports (it looks just like a Master System game) and one of the tennis games.

There are 4 options; CPC, Screen, Linear and Reverse. CPC is the standard one, Screen is basically a print screen of the image done in a complex way (it is easier to print screen via another emulator), Linear is used in a few games and Reverse is used in an very few games, so far only Amilie Minuit uses it for Amilie's walking poses and the regular CPC option displays the same sprites anyway. Please note that not all of the library have been tested (currently 80+ games) and some many use the other options.

Some games have a neat and tidy size set up fitting into a 16X16 square while others are completely random, in that case have the height being around 40 or so for less cropping. Then after that just print screen and paste the image on your prefered image editor, crop the sprites and paste. You might have to fiddle with the offset, width and height for every sprite as some games just do it in their own way with no standard.

After everything is done, the sprites have to be shrunk to 50% of their size since the tile viewer displays them twice the size despite the Zoom being at 1. This was spotted when you use the height function and it is displayed double in an image editor.

Please note: The tile viewer is not a miracle cure and your mileage may vary on the game that you are ripping. They might have everything, a certain amount, don't display sprites at all or have problems. Please see here on the issues that games suffer from and some are from well regarded games too.

Suggested Emulators

Due to the nature of the home computer and its Z80 processor, there are various emulators for the system. It is recommended to have more than one emulator because some games have copy protection that can fail on one emulator but can pass on another and there might not be a cracked version of the game. They also have their timing differences as well as what feature of the computer they emulate.

WinApe

WinApe is the most compatible emulator of the CPC emulators (out of the games tested only Mission Elevator fails), it can also emulate CPC+ and GX-4000 games too unlike the other emulators. It also has a tile viewer and the only emulator that has this feature for sprite ripping. Compatibility on computers is questionable where people have problems getting the emulator to work and it is not screenshot/capture friendly due to its slight blurry output that can not be fixed.

Sugarbox

A more recent emulator that has decent compatibility and has some copy protection schemes emulated but seems abandoned now. There is no pause button and the screenshot function does not work. It is also one of the few emulators that gets The Great Giana Sisters working without any graphical glitches.

CapriceForever

Like, Sugarbox it also has decent compatibility and is the only emulator to have its correct palette (WinApe is off by its middle values being too low, dsp needs some slight tweaks). It got 007: The Living Daylights to work that fails on most of the other emulators.

dsp

While it is a multi-purpose emulator, it does have decent Amstrad CPC emulation and is simple to use. While it is problematic with its compatibility with games with some games not working, there are plenty of games that do work and will get more accurate in the future. It is the only emulator that has the same screen size as its sprites with other emulators doubling with its display so it is recommended if you use the capture route. It also works on low powered computers at full speed.