Difference between revisions of "Apple IIGS emulators"
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|image=AppleIIGSPC.png | |image=AppleIIGSPC.png | ||
|imagecaption=An Apple II<span style="font-size:75%">GS</span> PC. | |imagecaption=An Apple II<span style="font-size:75%">GS</span> PC. | ||
− | |developer=Apple Computer, Inc. | + | |developer=[[Apple Inc.|Apple Computer, Inc.]] |
|type=[[:Category:Computers|Computers]] | |type=[[:Category:Computers|Computers]] | ||
|release=September 1986 | |release=September 1986 | ||
Line 11: | Line 11: | ||
|emulated={{✓}} | |emulated={{✓}} | ||
}} | }} | ||
− | |||
− | The [[Apple II Line|Apple II]]<span style="font-size:75%">GS</span> is a 16-bit PC produced by Apple Computer Inc. It was created to compete with the [[Amiga Line|Amiga]] and the [[Atari ST Line|Atari ST]] lines of PCs. | + | The '''[[Apple II Line|Apple II]]<span style="font-size:75%">GS</span>''' is a 16-bit PC produced by Apple Computer Inc. It was created to compete with the [[Amiga Line|Amiga]] and the [[Atari ST Line|Atari ST]] lines of PCs. |
Despite the Apple II<span style="font-size:75%">GS</span> name, it is a completely different architecture. The system has a chip called the “Mega II” which is an [[Apple II Line|Apple //e]] on a chip, making it fully backwards compatible with Apple ][ software. | Despite the Apple II<span style="font-size:75%">GS</span> name, it is a completely different architecture. The system has a chip called the “Mega II” which is an [[Apple II Line|Apple //e]] on a chip, making it fully backwards compatible with Apple ][ software. | ||
It was the first machine from Apple to use the Apple Desktop Bus and the first to provide a colour version of QuickDraw since the first colour Macintosh was not available until 1987. However it does not provide a high-resolution square pixel mode. | It was the first machine from Apple to use the Apple Desktop Bus and the first to provide a colour version of QuickDraw since the first colour Macintosh was not available until 1987. However it does not provide a high-resolution square pixel mode. | ||
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==Emulators== | ==Emulators== | ||
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{|class="wikitable" style="text-align:center" | {|class="wikitable" style="text-align:center" | ||
!scope="col"|Name | !scope="col"|Name | ||
− | !scope="col"| | + | !scope="col"|Platform(s) |
!scope="col"|Latest version | !scope="col"|Latest version | ||
+ | ! scope="col"|<abbr title="Free/Libre and Open-Source Software">FLOSS</abbr> | ||
!scope="col"|Active | !scope="col"|Active | ||
!scope="col"|[[Recommended Emulators|Recommended]] | !scope="col"|[[Recommended Emulators|Recommended]] | ||
+ | |- | ||
+ | ! colspan="7"|PC / x86 | ||
|- | |- | ||
|[[KEGS]] | |[[KEGS]] | ||
− | | | + | |align=left|{{Icon|Windows|Linux|macOS}} |
− | | | + | |[https://sourceforge.net/projects/kegs/files {{KEGSVer}}] |
− | |{{ | + | |{{✓}} |
+ | |{{✓}} | ||
|{{✓}} | |{{✓}} | ||
|- | |- | ||
|[[GSplus]] | |[[GSplus]] | ||
− | | | + | |align=left|{{Icon|Windows|Linux|macOS}} |
− | | | + | |[https://github.com/digarok/gsplus/releases {{GSplusVer}}] |
|{{✓}} | |{{✓}} | ||
+ | |{{✗}} | ||
|{{~}} | |{{~}} | ||
|- | |- | ||
− | |[ | + | |[https://david-schmidt.github.io/gsport GSport] |
− | | | + | |align=left|{{Icon|Windows|Linux|macOS}} |
− | | | + | |{{GSportVer}} |
− | |{{ | + | |{{✓}} |
+ | |{{✓}} | ||
|{{✗}} | |{{✗}} | ||
|- | |- | ||
|[[MAME]] | |[[MAME]] | ||
− | | | + | |align=left|{{Icon|Windows|Linux|macOS|FreeBSD}} |
− | |{{MAMEVer}} | + | |[http://www.mamedev.org/release.html {{MAMEVer}}] |
+ | |{{✓}} | ||
|{{✓}} | |{{✓}} | ||
|{{✗}} | |{{✗}} | ||
|} | |} | ||
+ | |||
+ | ==Processor== | ||
+ | |||
+ | The central processor is a 65816, a backwards-compatible 16-bit update to the 6502 that was also used in the Super Nintendo. It runs natively at 2.8Mhz but will slow down to ~1Mhz when in classic Apple II emulation mode or when writing to video memory. | ||
+ | |||
+ | ==Graphics Capabilities== | ||
+ | |||
+ | In addition to RGB emulations of the existing Apple II artefact composite video modes, the IIgs adds 320x200 and 640x200 RGB colour modes; the former in various combinations of 16 colours per line and the latter at 4 colours per line (including a hardware dithering mode that acts a little like 16 colours per line). Each line may use any of 16 palettes, making a total of 256 colours on screen without raster-linked palette changes. | ||
+ | |||
+ | There is also some support for 'fill mode', in which colour 0 means "repeat the last non-zero colour", designed to aid in fast single-colour fills. | ||
+ | |||
+ | Colours are selected from a 12-bit RGB 4,096 colour palette; the IIGS therefore has the same total colour range as its contemporaries the Commodore Amiga, the Atari STE and the Acorn Archimedes. | ||
+ | |||
+ | However it is subject to a number of deficiencies: there is a single buffer for video only — double buffering is not supported — and it supports neither hardware scrolling nor hardware sprites; and as all writes into video memory clock the CPU down to 1Mhz these are expensive to perform in software. | ||
+ | |||
+ | ==Audio Capabilities== | ||
+ | |||
+ | The IIGS provides a 32-channel wavetable Ensoniq sound chip, which uses 64kb for samples. | ||
+ | |||
+ | The OS by default configures this as 15 stereo channels and uses the remaining two channels as interrupt counters; the IIGS is therefore often described as a 15-channel machine. | ||
{{Apple}} | {{Apple}} | ||
+ | |||
+ | [[Category:Computers]] |
Revision as of 17:56, 6 July 2021
![]() | |
An Apple IIGS PC. | |
Developer | Apple Computer, Inc. |
---|---|
Type | Computers |
Release date | September 1986 |
Discontinued | December 1992 |
Predecessor | Apple II |
Emulated | ✓ |
The Apple IIGS is a 16-bit PC produced by Apple Computer Inc. It was created to compete with the Amiga and the Atari ST lines of PCs.
Despite the Apple IIGS name, it is a completely different architecture. The system has a chip called the “Mega II” which is an Apple //e on a chip, making it fully backwards compatible with Apple ][ software.
It was the first machine from Apple to use the Apple Desktop Bus and the first to provide a colour version of QuickDraw since the first colour Macintosh was not available until 1987. However it does not provide a high-resolution square pixel mode.
Emulators
Name | Platform(s) | Latest version | FLOSS | Active | Recommended | |
---|---|---|---|---|---|---|
PC / x86 | ||||||
KEGS | ![]() ![]() ![]() |
1.34 | ✓ | ✓ | ✓ | |
GSplus | ![]() ![]() ![]() |
0.14 | ✓ | ✗ | ~ | |
GSport | ![]() ![]() ![]() |
0.31 | ✓ | ✓ | ✗ | |
MAME | ![]() ![]() ![]() ![]() |
0.264 | ✓ | ✓ | ✗ |
Processor
The central processor is a 65816, a backwards-compatible 16-bit update to the 6502 that was also used in the Super Nintendo. It runs natively at 2.8Mhz but will slow down to ~1Mhz when in classic Apple II emulation mode or when writing to video memory.
Graphics Capabilities
In addition to RGB emulations of the existing Apple II artefact composite video modes, the IIgs adds 320x200 and 640x200 RGB colour modes; the former in various combinations of 16 colours per line and the latter at 4 colours per line (including a hardware dithering mode that acts a little like 16 colours per line). Each line may use any of 16 palettes, making a total of 256 colours on screen without raster-linked palette changes.
There is also some support for 'fill mode', in which colour 0 means "repeat the last non-zero colour", designed to aid in fast single-colour fills.
Colours are selected from a 12-bit RGB 4,096 colour palette; the IIGS therefore has the same total colour range as its contemporaries the Commodore Amiga, the Atari STE and the Acorn Archimedes.
However it is subject to a number of deficiencies: there is a single buffer for video only — double buffering is not supported — and it supports neither hardware scrolling nor hardware sprites; and as all writes into video memory clock the CPU down to 1Mhz these are expensive to perform in software.
Audio Capabilities
The IIGS provides a 32-channel wavetable Ensoniq sound chip, which uses 64kb for samples.
The OS by default configures this as 15 stereo channels and uses the remaining two channels as interrupt counters; the IIGS is therefore often described as a 15-channel machine.
Apple Inc. | |
---|---|
Desktop: Apple I • Apple II Line (Apple IIGS) • Apple III line • Lisa • Macintosh line • MacOS Mobile: iPod • iOS Consoles: Pippin |