Try it out.The Mini vMac emulator collection allows modern computers to run software made for early Macintosh computers, the computers that Apple sold from 1984 to 1996 based upon Motorolas 680x0 microprocessors. Basilisk II Classic Macintosh emulator in the browser. Production of the Classic was prompted by the success of the Original Macintosh, then the Macintosh Plus and finally the Macintosh SE.The system specifications of the Classic are very similar to. It was the first Macintosh to sell for less than US1,000. From October 1990 to September 1992. The Macintosh Classic was a personal computer designed, manufactured and sold by Apple Computer, Inc.Mac OS 7.5.2 was released in 1995 and in turn SheepShaver doesn’t fit my criteria of sticking to software. If you’re interested in running the more recent versions of Classic Mac OS this is probably the emulator you should choose. It’s capable of running Mac OS 7.5.2 through 9.0.4.
Classic Emulator Collection Mac Emulator CollectionI've been hoping to get it running for some time, and previously made an attempt back in 2013, before switching to focus on the PCE emulator. Whilst Infogrames classic strategy.I recently ported the Basilisk II Classic Macintosh emulator to run in a web browser. Amstrad CPC-Emulator based on JEMU by R. Medieval 2 total war kingdoms no cd crack downloadHow it worksThe emulator code is compiled with Emscripten and run in a Web Worker. Anyway, let's get into the gory technical details of how it works. The Basilisk II port is the culmination of both of these things. Citrix receiver for mac 1068 downloadI experimented with locking the video surface when reading and writing, but this hurt performance due to lock contention. This shared memory is read from the main thread here and output onto a Canvas. In video_sdl.cppWhere the EM_ASM_ macro is used to call this JS function to copy the contents of the video framebuffer to a SharedArrayBuffer. Emscripten provides an implementation of SDL for the browser, but this implementation isn't designed to run in a web worker, so I've hacked the emulator's video output code to write to the SharedArrayBuffer instead of calling SDL APIs. VideoThe original emulator codebase makes use of SDL (a cross-platform set of video/audio/input APIs). This allows the simulation to be more smooth, as the emulator thread can just focus on simulating the Macintosh computer, and leave the tasks of displaying the contents of the video framebuffer and playing audio up to the main (browser) thread. The emulator thread will ensure that there are several buffers of audio queued up, to avoid gaps in playback in the case of a slowdown. AudioThe implementation of audio uses a queue of buffers in shared memory, which each have a flag signifying whether they are full and ready to be consumed by the UI thread, or empty and ready to be written by the emulator thread. I also had to add a mapping to convert JS keycodes to ADB (Apple) keycodes. InputMouse and keyboard input are communicated via another SharedArrayBuffer here in the UI thread JS, then read in the worker thread JS here, when requested from the C code here. We could improve on this by using a circular queue of framebuffers for alternating frames (multiple buffering), which would allow locking (with less contention), but in practice this is okay. Even if the UI thread reads a frame from the video framebuffer while it is currently in the middle of being written to from the emulator worker, it's not really noticable, because in the shared memory the new frame contents is just being written directly over the old one at the same position, so visually it just presents as a bit of 'tearing' (showing part of the old frame, part of the new frame). ![]() The JS would simply read and write values on the C heap. Instead of creating SharedArrayBuffers to communicate video, audio, and input, Emscripten's pthreads mode makes the entire C heap memory space a SharedArrayBuffer, with each spawned thread running in a web worker. In this scenario the emulator code would start up, spawn a thread to run the emulator main loop, and then yield back to the browser. Potential ImprovementsIn future this implementation could be improved by moving all of the shared memory communication to C code by leveraging Emscripten's pthreads support.
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