5 ms·
A cycle-accurate IBM PC emulator in your web browser
- GloriousCow 1y agoMartyPC brings cycle-accurate IBM PC emulation to your web browser. Run Area 5150 at 60fps on your phone! Almost every feature from the desktop version is present if practical: - View the realtime state of nearly every component of the system. - View live disassembly of CPU instructions. - Edit registers and memory. - Slow down or speed up the system. - Peek on how games draw their graphics with the Memory Visualizer.
- WalterGR 1y agoPretty incredible! I’m on mobile right now so I can only comment on the demo that runs automatically, which I understand isn’t the _point_. :) More about the demo: https://www.vogons.org/viewtopic.php?t=89435 https://www.vogons.org/viewtopic.php?t=89435 (For those unfamiliar with “demo” in this context, see https://en.m.wikipedia.org/wiki/Demoscene https://en.m.wikipedia.org/wiki/Demoscene) I look forward to checking out the features you mention on a proper computer.
- rkagerer 1y agoI loved it when the Doom floating head demon guy came up. Right when y'all were about to ask "...but can it run Doom?"
- TMWNN 1y agoThanks for pointing people to Area 5150. Context for others: This, and its predecessor 8088 MPH, uses every single trick in the book and many not written down anywhere to squeeze that kind of performance out of a real 1981 IBM PC 5150 with IBM CGA card. Thus they only run correctly on that specific hardware, not a clone computer or card. "Regular" software emulators also have a tough time. Showing off MartyPC with Area 5150 is thus two technical feats combined into one.
- theogravity 1y agoThat demo was pretty mesmerizing!
- nsxwolf 1y agoCan you imagine sending an Area 5150 disk back in time to 1981?
- trollbridge 1y agoYou’d be fussing around trying to find enough RAM expansion cards to get your system to 640K (including hot patching the BIOS since it had a bug that it could only get to 544K).
- SoftTalker 1y agoOught to be enough for anyone.
- voidspark 1y ago640 KB in 1981 was more expensive than 640 GB today.
- ForOldHack 1y agoThat was only the first 64k motherboard. ( Five slots only ). Fixed with the PC that came out less than two years later. My brothers machine only had 384k, and it was more than enough. Only three years after, I built 10Mhz XT w/ a V20 640k running Xenix.
- shakna 1y agoOne of my neighbours in Sydney sold a board he made in his garage, that gave you an extra ten slots, which I filled with way too much RAM. Sort of like a homebrewed 5161, before the 5161 existed.
- trollbridge 1y agoThat's kind of neat. Did he just extend the bus in a "raw" fashion or put buffers on it? (The downside of the 5161 was any memory device in the 5161 had an extra wait state thanks to the speed of the buffers, which were necessary to deal with the capacitance on the cable to the expansion unit.)
- wbhart 1y agoI've been using MartyPC for a few years and except for emulating glitches in hardware which depend on the manufacturer, date of manufacture or even temperature, it is getting harder to find cycle accurate tricks that MartyPC can't emulate perfectly (believe me, we've been trying). The whole thing is a marvel of software engineering! What is remarkable is that the author (GloriousCow) doesn't complain that people are ripping off his code and ideas, but that more people haven't used his learnings to create other cycle accurate emulators for the PC.
- johnklos 1y agoTemperature? Really? How does that work?
- bonzini 1y agoIf you program a register at a moment and in a way that causes two signals to "collide", the result effectively depends on transistor behavior. That in turn can be temperature dependent. For an example on the PC see https://int10h.org/blog/2023/03/cga-6845-crtc-phantom-vsync-glitch/ https://int10h.org/blog/2023/03/cga-6845-crtc-phantom-vsync-...
- creatonez 1y agoThanks. Transistor level race conditions will keep me up at night.
- kaoD 1y agoAmazing link. Thanks for sharing. Where can I find more writeups like this?
- mrandish 1y agoThat was a fun rabbit hole. My first computer (8-bit, 4k RAM, 0.8 Mhz) had a video chip related to that 6845, the 6847, which was (sadly) a somewhat lower cost, less capable, less interesting chip.
- dosman33 1y agoI miss Notacon and Jason Scott's Demoscene parties.
- imroot 1y agoSome of my best hacker/nerd friends I met at notacon. It had a vibe that no other con I’ve been to has had.
- p0w3n3d 1y agoWow that's amazing. I sometimes play NES emulated games, which are (due to hardware limitations) using some tricks while displaying larger mobs, to show a few sprites instead of one (and using monitor synch to quickly switch the sprites in between switching to another scanline). This however renders as blinking in my emulator. I can only imagine that this demo was doing similar tricks to "push the limits" on CGA. Also, I remember my i386-33SX playing full 4 channel music on the PC Speaker in the game "Pinball Fantasies". This was state-of-the-art (also not working properly on DOSBox emulator nowadays)
- marstall 1y agotruly epic!
- genewitch 1y agoThis appeared on the fp the same day i spent 15 hours trying to get various old/weird OSes installed. Xerox Star (viewpoint), os/2 warp 4, serenityos, debian 9, and where is freebsd 2.2 disc 2, might i ask? commenting for posterity, and to say the web emulator is very slick, i have some dos diskettes to try out.