Kent's Emulated GS
by Kent Dickey
"KEGS is an Apple //gs emulator for X windows, but optimized for HP workstations. KEGS is now portable to two other platforms-- Linux on Intel x86 and Linux on PowerPC machines. KEGS was originally written for HP Unix workstations using a hand-coded assembly language interpreter loop. To open KEGS up to a wider audience, I recoded the assembly parts into a C-only version, which can now be compiled and run on other platforms. The Linux port was very easy since only a few dozen lines of code needed to change. See README.compile.

"KEGS uses X-Windows for its display (you can send the display to another machine) and uses the built-in audio on HP workstations to emulate all Apple //gs sounds. It supports limited serial port emulation through sockets. Audio does not work under Linux yet.

"The ROMs and GS/OS (the Apple //gs operating system) are not included with KEGS since they are not freely distributable. KEGS is a little user-hostile now, so if something doesn't work, let me know what went wrong, and I'll try to help you out. See my email address at the end of this file." Features:

  • Fast 65816 emulation
  • Assembly version: about 8MHz on a 712/80, and 17-20MHz on a C180.
  • C version: about 4MHz on a 712/80, 12MHz on a 266MHz Pentium II.
  • About 13MHz on a 240MHz 604e PowerCenter 240 running MkLinux.
  • Emulates low-level 5.25" and 3.5" drive accesses (even nibble-copiers work!).
  • Emulates classic Apple II sound and 32-voice Ensoniq sound.
  • All sound is played in 16-bit stereo at 48KHz. (Not on Linux, yet).
  • Emulates all Apple //gs graphics modes, including border effects.
  • Can handle mixed-displays (superhires at the top, lores at the bottom).
  • Always does 60 video updates per second.
  • Mouse and joystick support (although the joystick is hard to use).
  • Emulates all Apple //gs memory "tricks" for full compatibility.
  • Low-level ADB keyboard and mouse emulation enables Wolfenstein 3D to run.
  • Clock chip emulation makes the Unix time available to the Apple //gs.
  • Emulated battery RAM remembers control panel settings.
  • Limited SCC (serial port) emulation to enable PR#1/2 IN#1/2 and other
  • serial programs to work, but it is still a bit buggy.
  • KEGS always emulates a 4MB Apple //gs. I may make the amount of Apple //gs memory a command line option in the future.
  • KEGS is so accurate, even the built-in ROM selftests pass (you must be in 2.5MHz speed mode to pass the self-tests).
Download KEGS
KEGS for HP-UX and Linux [Homepage]
. Apple II / Apple IIGS Emulators Index . Emulators Index . Front Page .
© 1997/1998 Archaic Ruins