6 ms·

PCem – An emulator for various old PCs

90 points by vmorgulis 10y ago

gcb0 10y ago
what is this? qemu? site nor repo has any description or faq
- voltagex_ 10y ago
  Nope, appears to be a completely different emulator. Looks to have been initially Windows only, although there's a version for Linux now.
  - Narishma 10y ago
    There's a Linux version but it is pretty much unmaintained. It receives the occasional update but it's slower than the Windows version, has less features and the UI is terrible.
    - gcb0 10y ago
      alrigth then. let's fire up virtual box with a Windows image to check this out :D
smegel 10y ago
Wonder if this will replace DOSBox which is derelict.
- voltagex_ 10y ago
  I don't think DOSBox is "derelict". http://source.dosbox.com/dosboxsvn.txt http://source.dosbox.com/dosboxsvn.txt
  - richard_todd 10y ago
    It might not be, but it's easy to understand why a casual observer would think so. The latest news on the dosbox website is from 2013, and the latest version (0.74) was released in 2010 according to the date on the sourceforge download page. I wonder why they have not made another official release?
    - werdna123 10y ago
      Idk, probably because it works great
    - voltagex_ 10y ago
      Interestingly, GOG (Good Old Games) are quite happy to ship 0.74 (including wasting 1.5 megabytes of space in most games by shipping the source) with their commercial games - even the latest one 11 days ago (yes, I bought it just to check!) https://www.gog.com/forum/general/whats_the_latest_dosbox_based_game_released_on_gog https://www.gog.com/forum/general/whats_the_latest_dosbox_ba...
      - detaro 10y ago
        the "wasted" 1.5 MB probably are the simplest way for them to be sure to be GPL compliant.
        voltagex_ 10y ago
        True, but wouldn't they be compliant pointing to http://gog.com/dosbox http://gog.com/dosbox as well?
        detaro 10y ago
        I think that would work just as well and would have been my first idea too, but IMHO it's kind of an elegant solution to do it this way. The recipient can very easily find the exact version used and they don't have to maintain that information somewhere else. Especially if they add specific patches -> I know that they often modify the game binaries, but maybe they have custom DOSbox changes as well.
  - smegel 10y ago
    Interesting, I had heard about a "Daum Branch" but I didn't know the main trunk was that active. As a completely irrelevant trivia, if you play games on DosBOX, try and use them with Munt (Roland MT32 emulator) if they support Roland MIDI. I am currently playing Police Quest 1 (VGA) and it sounds amazing.
    - voltagex_ 10y ago
      >Daum branch Last updated in 2015 - http://ykhwong.x-y.net/ http://ykhwong.x-y.net/ Reminds me of the Gameboy Advance emulation scene and the mess that was VBA - eventually mainline was abandoned, VBA-m seems to be the maintained fork, but there's also VBA-rr.
      - qwertyuiop924 10y ago
        Thankfully, us linux users have a good gba emulator now. Windows already had the legendary no$gba. And what about the PS emu scene? PCSX is dead, so your choice is between PCSXr, and ePSXe. There are meaningful differences between the two, but it's pretty hard to know that up front. The DC emu scene is almost nonexistant, all the emulators have been abandoned, none of them work on Linux (Reicast claims to, but it doesn't: I've tried), and even on windows, most games barely run, if at all. And then there's the NES emulation scene on GBA: pocketnes is the best emulator by far (it's amazing), and you can find copies floating around, but you need a pocketnes rom maker to build the roms, and that's hard to find, especially on unix. The only one I've found for unix is mkrom, and good luck getting your hands on it: I had to trawl archive.org for hours to find a copy.
        Narishma 10y ago
        The best (most accurate) PS1 emulator is mednafen I believe.
        qwertyuiop924 10y ago
        I haven't used it, but I don't trust multi-system emulators as a rule. Especially after my many bad experiences with RetroArch.
- vog 10y ago
  DOSBox seems to have a second life through its JavaScript port EM-DOSBox, which appears to be quite active: https://github.com/dreamlayers/em-dosbox/commits/em-dosbox-svn-sdl2 https://github.com/dreamlayers/em-dosbox/commits/em-dosbox-s... That one became very popular through the use at the "MS-DOS Games" section of archive.org: https://archive.org/details/softwarelibrary_msdos_games https://archive.org/details/softwarelibrary_msdos_games
- amyjess 10y ago
  Spend some time playing around with PCem, and you'll find that the emulated machine runs at the same speed as the original hardware. In fact, PCem emulates every facet of the hardware: you're not just running a DOS environment, you're emulating an entire computer from end to end. You may not want to sit through an XT boot sequence every time you want to fire up an old game. Accurate emulators like PCem serve an important niche which is very different than quick-and-dirty environments like DOSBox. PCem and similar emulators aim to preserve thorough documentation of the hardware ("hardware preservation project" is probably a better term than "emulator" here), and they're also useful for running specialized software that doesn't work unless the emulation is 100% accurate. But if you just want to play a random old game, and it doesn't take advantage of specific hardware quirks, you'd be better off with DOSBox. Edit: Also, PCem needs BIOS ROMs to work, while DOSBox doesn't. This makes it easier for companies like GOG to ship DOSBox; if they shipped PCem instead, they'd have to either illegally include the ROMs (which will bring down the wrath of IBM's lawyers) or leave ROM acquisition as an exercise to the user, who won't be pleased at having to hunt down ROMs to play a game they bought on GOG.
  - gattilorenz 10y ago
    This. PCem can run stuff (most) other emulators have trouble with. One example being Xenix 8086 which, to my knowledge, works only on MESS and PCem. And, comparing the usability of both, MESS doesn't seem an unappropriate name.
    - anthk 10y ago
      It should work under Bochs.
ilaksh 10y ago
Whats the point of emulating all of these variants? Aren't they all similar enough that you can run the software with just one particular machine emulated and it would work almost identically? I thought that was the whole point of the PC.
- werdna123 10y ago
  A goal of x86 was backwards compatibility, but it has never been perfect, i.e. when software was written that relied on undefined behavior that later chips implement differently, etc.
- rpiguy 10y ago
  Your statement mostly applies to the AT/286 era and beyond. Very early PCs were not clones but rather MS DOS compatible which is different (BIOS was not compatible). Even when true clones appeared with compatible BIOS system designers like Tandy would try to innovate with things like "Tandy Graphics and Sound" which are sort of PC Jr graphics but not quite, etc. Having the ability to emulate the older machines is a boon to gamers. However, I have no idea why anyone would want to emulate Cyrix chips or later PCs other than out of curiosity. A lot on this list does seem superfluous.
  - Narishma 10y ago
    This is still useful as there are plenty of early Windows games that don't work correctly (if at all) anymore on modern systems.
  - Sanddancer 10y ago
    The collection of supported machines does seem to concentrate mostly on the older systems. The newer ones seem to be examples of the interesting quirks that were in place in the later days -- ATI's WinBIOS for example, or Compaq's machines which used a stripped down copy of Windows 3.1 as the bios utility. Gut feeling for the newer systems is mostly to couple with the newer video cards on the list -- the S3 Trio64 and the 3dfx VooDoo.
  - IntelMiner 10y ago
mycall 10y ago
I wonder if it includes the BASIC ROM chip.
- Narishma 10y ago
  It doesn't. You have to provide the ROM files yourself.
dancek 10y ago
The sources for the emulated devices are very interesting to read. E.g. https://bitbucket.org/pcem_emulator/pcem/src/c3548dff8c8b235bde952201154a8eb340613272/src/vid_s3.c?at=default&fileviewer=file-view-default https://bitbucket.org/pcem_emulator/pcem/src/c3548dff8c8b235... I imagine the emulations are based on some public docs or existing driver implementations, and probably not completely accurate--but accurate enough to work with some (most?) drivers. Emulating a lot of old hardware at that level is impressive.
throwaway7767 10y ago
Really hope PCem gets network support at some point. There was a branch implementing ne2k support but it's old and didn't apply to master cleanly last I checked. Setting up an OS on it was a bit of a pain in the ass, the only way to transfer files was to create ISOs with them and mount them in the emulator.

90 points by vmorgulis 10y ago

gcb0 10y ago

what is this? qemu? site nor repo has any description or faq

voltagex_ 10y ago
Nope, appears to be a completely different emulator. Looks to have been initially Windows only, although there's a version for Linux now.
- Narishma 10y ago
  There's a Linux version but it is pretty much unmaintained. It receives the occasional update but it's slower than the Windows version, has less features and the UI is terrible.
  - gcb0 10y ago
    alrigth then. let's fire up virtual box with a Windows image to check this out :D

smegel 10y ago

Wonder if this will replace DOSBox which is derelict.

voltagex_ 10y ago
I don't think DOSBox is "derelict". http://source.dosbox.com/dosboxsvn.txt http://source.dosbox.com/dosboxsvn.txt
- richard_todd 10y ago
  It might not be, but it's easy to understand why a casual observer would think so. The latest news on the dosbox website is from 2013, and the latest version (0.74) was released in 2010 according to the date on the sourceforge download page. I wonder why they have not made another official release?
  - werdna123 10y ago
    Idk, probably because it works great
  - voltagex_ 10y ago
    Interestingly, GOG (Good Old Games) are quite happy to ship 0.74 (including wasting 1.5 megabytes of space in most games by shipping the source) with their commercial games - even the latest one 11 days ago (yes, I bought it just to check!) https://www.gog.com/forum/general/whats_the_latest_dosbox_based_game_released_on_gog https://www.gog.com/forum/general/whats_the_latest_dosbox_ba...
    - detaro 10y ago
      the "wasted" 1.5 MB probably are the simplest way for them to be sure to be GPL compliant.
      - voltagex_ 10y ago
        True, but wouldn't they be compliant pointing to http://gog.com/dosbox http://gog.com/dosbox as well?
        detaro 10y ago
        I think that would work just as well and would have been my first idea too, but IMHO it's kind of an elegant solution to do it this way. The recipient can very easily find the exact version used and they don't have to maintain that information somewhere else. Especially if they add specific patches -> I know that they often modify the game binaries, but maybe they have custom DOSbox changes as well.
- smegel 10y ago
  Interesting, I had heard about a "Daum Branch" but I didn't know the main trunk was that active. As a completely irrelevant trivia, if you play games on DosBOX, try and use them with Munt (Roland MT32 emulator) if they support Roland MIDI. I am currently playing Police Quest 1 (VGA) and it sounds amazing.
  - voltagex_ 10y ago
    >Daum branch Last updated in 2015 - http://ykhwong.x-y.net/ http://ykhwong.x-y.net/ Reminds me of the Gameboy Advance emulation scene and the mess that was VBA - eventually mainline was abandoned, VBA-m seems to be the maintained fork, but there's also VBA-rr.
    - qwertyuiop924 10y ago
      Thankfully, us linux users have a good gba emulator now. Windows already had the legendary no$gba. And what about the PS emu scene? PCSX is dead, so your choice is between PCSXr, and ePSXe. There are meaningful differences between the two, but it's pretty hard to know that up front. The DC emu scene is almost nonexistant, all the emulators have been abandoned, none of them work on Linux (Reicast claims to, but it doesn't: I've tried), and even on windows, most games barely run, if at all. And then there's the NES emulation scene on GBA: pocketnes is the best emulator by far (it's amazing), and you can find copies floating around, but you need a pocketnes rom maker to build the roms, and that's hard to find, especially on unix. The only one I've found for unix is mkrom, and good luck getting your hands on it: I had to trawl archive.org for hours to find a copy.
      - Narishma 10y ago
        The best (most accurate) PS1 emulator is mednafen I believe.
        qwertyuiop924 10y ago
        I haven't used it, but I don't trust multi-system emulators as a rule. Especially after my many bad experiences with RetroArch.
vog 10y ago
DOSBox seems to have a second life through its JavaScript port EM-DOSBox, which appears to be quite active: https://github.com/dreamlayers/em-dosbox/commits/em-dosbox-svn-sdl2 https://github.com/dreamlayers/em-dosbox/commits/em-dosbox-s... That one became very popular through the use at the "MS-DOS Games" section of archive.org: https://archive.org/details/softwarelibrary_msdos_games https://archive.org/details/softwarelibrary_msdos_games
amyjess 10y ago
Spend some time playing around with PCem, and you'll find that the emulated machine runs at the same speed as the original hardware. In fact, PCem emulates every facet of the hardware: you're not just running a DOS environment, you're emulating an entire computer from end to end. You may not want to sit through an XT boot sequence every time you want to fire up an old game. Accurate emulators like PCem serve an important niche which is very different than quick-and-dirty environments like DOSBox. PCem and similar emulators aim to preserve thorough documentation of the hardware ("hardware preservation project" is probably a better term than "emulator" here), and they're also useful for running specialized software that doesn't work unless the emulation is 100% accurate. But if you just want to play a random old game, and it doesn't take advantage of specific hardware quirks, you'd be better off with DOSBox. Edit: Also, PCem needs BIOS ROMs to work, while DOSBox doesn't. This makes it easier for companies like GOG to ship DOSBox; if they shipped PCem instead, they'd have to either illegally include the ROMs (which will bring down the wrath of IBM's lawyers) or leave ROM acquisition as an exercise to the user, who won't be pleased at having to hunt down ROMs to play a game they bought on GOG.
- gattilorenz 10y ago
  This. PCem can run stuff (most) other emulators have trouble with. One example being Xenix 8086 which, to my knowledge, works only on MESS and PCem. And, comparing the usability of both, MESS doesn't seem an unappropriate name.
  - anthk 10y ago
    It should work under Bochs.

ilaksh 10y ago

Whats the point of emulating all of these variants? Aren't they all similar enough that you can run the software with just one particular machine emulated and it would work almost identically? I thought that was the whole point of the PC.

werdna123 10y ago
A goal of x86 was backwards compatibility, but it has never been perfect, i.e. when software was written that relied on undefined behavior that later chips implement differently, etc.
rpiguy 10y ago
Your statement mostly applies to the AT/286 era and beyond. Very early PCs were not clones but rather MS DOS compatible which is different (BIOS was not compatible). Even when true clones appeared with compatible BIOS system designers like Tandy would try to innovate with things like "Tandy Graphics and Sound" which are sort of PC Jr graphics but not quite, etc. Having the ability to emulate the older machines is a boon to gamers. However, I have no idea why anyone would want to emulate Cyrix chips or later PCs other than out of curiosity. A lot on this list does seem superfluous.
- Narishma 10y ago
  This is still useful as there are plenty of early Windows games that don't work correctly (if at all) anymore on modern systems.
- Sanddancer 10y ago
  The collection of supported machines does seem to concentrate mostly on the older systems. The newer ones seem to be examples of the interesting quirks that were in place in the later days -- ATI's WinBIOS for example, or Compaq's machines which used a stripped down copy of Windows 3.1 as the bios utility. Gut feeling for the newer systems is mostly to couple with the newer video cards on the list -- the S3 Trio64 and the 3dfx VooDoo.
- IntelMiner 10y ago

mycall 10y ago

I wonder if it includes the BASIC ROM chip.

Narishma 10y ago
It doesn't. You have to provide the ROM files yourself.

dancek 10y ago

The sources for the emulated devices are very interesting to read. E.g. https://bitbucket.org/pcem_emulator/pcem/src/c3548dff8c8b235bde952201154a8eb340613272/src/vid_s3.c?at=default&fileviewer=file-view-default https://bitbucket.org/pcem_emulator/pcem/src/c3548dff8c8b235... I imagine the emulations are based on some public docs or existing driver implementations, and probably not completely accurate--but accurate enough to work with some (most?) drivers. Emulating a lot of old hardware at that level is impressive.

throwaway7767 10y ago

Really hope PCem gets network support at some point. There was a branch implementing ne2k support but it's old and didn't apply to master cleanly last I checked. Setting up an OS on it was a bit of a pain in the ass, the only way to transfer files was to create ISOs with them and mount them in the emulator.