6 ms·

TIS-100: An emulator for a CPU that doesn't exist

80 points by EvilTrout 11y ago

DanWaterworth 11y ago
It would be interesting to implement the emulator using the PyPy toolchain.
tehbeard 11y ago
To be fair the TIS-100 runs slower in the game to improve the visuals. To let you see (albeit in a blur at higher speeds) your code run rather than a click button, instant "level complete" popup. (note: I don't own TIS-100 yet, but it's fairly similar to their other game spacechem)
kyberias 11y ago
Remember that notch's silly space game with a simulated processor and the huge influx of emulators and whatnot after the announcement?
- Zardoz84 11y ago
  There is a lot of DCPU-16 emulators on the wild. Also, there is a few successor games projects of 0x10c that uses DCPU-16 or his own cpu's
LoSboccacc 11y ago
oh this brings up memories of corewars and redcode
SIGALARM 11y ago
it's only a matter of time before someone runs linux on it.
- npongratz 11y ago
  Doubtful. Having only one usable register (plus another non-addressable "backup" register) places a (IMO) insurmountable constraint on running any multiuser unix-like kernel.
  - falcolas 11y ago
    Well, the trick to the game is that you have multiple cores, each with their own register and a pipeline between them. This effectively gives you six registers, since you can bounce values back from the core on an edge register. There are also "stack" cores, which store an arbitrary number of values and allow you to pop them back off. If you were able to expand the system to have N cores of any type, I could easily imagine someone being able to compile C down to it.
    - npongratz 11y ago
      That's a great point. Using other cores' registers is required to pass many scenarios in the game, and I'm embarrassed I forgot about the technique after being away for only a few days :) Thank you!
    - Zardoz84 11y ago
      So Transputers again
hthh 11y ago
I too wrote a TIS-100 simulator in C ( https://github.com/hthh/tis100sim https://github.com/hthh/tis100sim ) - it's interesting to compare styles. (I get a bunch of errors on OS X unless I change "CC=gcc" to "CC=clang", btw)
- jeffreyrogers 11y ago
  That gcc error is strange, since I think in the recent versions of OS X gcc is just an aliases for clang. Here's my output of `gcc --version` on OS X 10.10: Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1 Apple LLVM version 6.1.0 (clang-602.0.53) (based on LLVM 3.6.0svn) Target: x86_64-apple-darwin14.3.0 Thread model: posix edit: also, should've said that's really cool and thanks for posting your source code.
  - hthh 11y ago
    My GCC seems to be GCC (don't remember why - I guess I installed it for something). I can also make it build using "--std=c99" (but that makes the undefined behavior mentioned in issue #2 show up, which is why I went with clang). gcc: warning: couldn't understand kern.osversion '14.3.0 gcc (GCC) 4.8.2 Copyright (C) 2013 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
- david-given 11y ago
  Well, I wrote one in Haskell, so there! (Currently trapped in legal hell. I work for one of those annoying companies that claims ownership of everything I do, even in my personal time, so I have to get it cleared before I can push it to github...) I added some extensions to allow one node to program another; the PROGRAM <dir> opcode resets the node in that direction, and it can then be fed a series of numbers which form the program. Once complete it starts executing. With this, it ought to be possible to program an arbitrary network with programs from a boot ROM attached to a single node at the corner. It would have to propagate the distribution program through the network, which would then in turn propagate the program to the right place and reprogram each node in turn. Because a programmed node wouldn't contain the distribution program any more we'd have to start at the outer edge and work inwards. I do wonder whether it would be possible to get real work done with this. I bet a node could be implemented in a tiny handful of FPGA gates.
FreeFull 11y ago
http://retroforth.org/docs/The_Ngaro_Virtual_Machine.html http://retroforth.org/docs/The_Ngaro_Virtual_Machine.html This virtual machine has been implemented many times in various programming languages. The retro forth download includes most of the implementations.
vanderZwan 11y ago
The game itself I love. But I have some issues with it's implementation. To be specific, it maxes out the CPU even when it's not doing anything. Given that it's supposed to emulate low-level hardware, at very slow speeds, and does not have any demanding graphics, I fail to see why it should do that. (It's something I've seen happening in more games as of late, actually. For example, Desktop Dungeons - a very fun game which has no business demanding anything from my computer since it's turn-based, uses sprites, and barely animated. And yet my laptop heats up as soon as I open the game.) In fact, it's a bit ironic, given that the whole theme of the game is squeezing out performance out of bare metal hardware, and I admit that I'm more annoyed by it for that somewhat irrational reason.
- falcolas 11y ago
  It's still in early access, perhaps a bug report to the developer would be in order? It doesn't do this on my machine, so it might not be occurring for them.
  - vanderZwan 11y ago
    I am running Linux, I have to admit. Could be poor Unity support in that regard.
- lfowles 11y ago
  This is common with games nowadays. Almost no one throttles the game loop outside of mobile I guess. I've had the same issue with the Analog/Hate _visual novel_ series. My laptop doesn't need to turn into a lapheater for some text....
- yoklov 11y ago
  IIRC TIS-100 is implemented using Unity, which doesn't really give you a lot of leeway as to when you update and render (e.g. you choose a framerate and it renders and updates your objects at that rate). Admittedly, since most of the time in TIS100 the screen does not change, if it were implemented using a custom engine this could be fixed. For desktop dungeons, I'm not aware of the specifics about that game (though I have played it), but generally, if you're using OpenGL or DirectX to render, repainting only part of the screen isn't an option, so if anything is animated (no matter how slight the animation), you have to redraw the screen every frame. There are exceptions to this (like the mouse pointer, although this requires platform specific code), but not many of them.
cmdrfred 11y ago
Is this a good way to get started with assembly?
- markdeloura 11y ago
  It doesn't have much in the way of a tutorial yet - this PDF might be a better place to grow your understanding of Assembly Language: http://www.drpaulcarter.com/pcasm/ http://www.drpaulcarter.com/pcasm/
  - cmdrfred 11y ago
    Thanks for the tip.
bashinator 11y ago
Zachtronics makes amazing games. This is the same guy who wrote SpaceChem and Infiniminer (the inspiration for Minecraft) http://www.zachtronics.com/ http://www.zachtronics.com/
static_noise 11y ago
MMIX
chetanahuja 11y ago
I've been looking for a simple computer/CPU simulator for kids to play on. Something like this http://thlorenz.com/visulator/ http://thlorenz.com/visulator/ is almost there but it's a bit too complex for elementary/middle school level kids to start on. A game would be even better but the one we're discussing here (TIS-100) is basically designed to confuse and challenge rather than illuminate. Suggestions and pointers are extremely welcome.

80 points by EvilTrout 11y ago

It would be interesting to implement the emulator using the PyPy toolchain.

To be fair the TIS-100 runs slower in the game to improve the visuals. To let you see (albeit in a blur at higher speeds) your code run rather than a click button, instant "level complete" popup. (note: I don't own TIS-100 yet, but it's fairly similar to their other game spacechem)

kyberias 11y ago

Remember that notch's silly space game with a simulated processor and the huge influx of emulators and whatnot after the announcement?

Zardoz84 11y ago
There is a lot of DCPU-16 emulators on the wild. Also, there is a few successor games projects of 0x10c that uses DCPU-16 or his own cpu's

LoSboccacc 11y ago

oh this brings up memories of corewars and redcode

SIGALARM 11y ago

it's only a matter of time before someone runs linux on it.

npongratz 11y ago
Doubtful. Having only one usable register (plus another non-addressable "backup" register) places a (IMO) insurmountable constraint on running any multiuser unix-like kernel.
- falcolas 11y ago
  Well, the trick to the game is that you have multiple cores, each with their own register and a pipeline between them. This effectively gives you six registers, since you can bounce values back from the core on an edge register. There are also "stack" cores, which store an arbitrary number of values and allow you to pop them back off. If you were able to expand the system to have N cores of any type, I could easily imagine someone being able to compile C down to it.
  - npongratz 11y ago
    That's a great point. Using other cores' registers is required to pass many scenarios in the game, and I'm embarrassed I forgot about the technique after being away for only a few days :) Thank you!
  - Zardoz84 11y ago
    So Transputers again

hthh 11y ago

I too wrote a TIS-100 simulator in C ( https://github.com/hthh/tis100sim https://github.com/hthh/tis100sim ) - it's interesting to compare styles. (I get a bunch of errors on OS X unless I change "CC=gcc" to "CC=clang", btw)

jeffreyrogers 11y ago
That gcc error is strange, since I think in the recent versions of OS X gcc is just an aliases for clang. Here's my output of `gcc --version` on OS X 10.10: Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1 Apple LLVM version 6.1.0 (clang-602.0.53) (based on LLVM 3.6.0svn) Target: x86_64-apple-darwin14.3.0 Thread model: posix edit: also, should've said that's really cool and thanks for posting your source code.
- hthh 11y ago
  My GCC seems to be GCC (don't remember why - I guess I installed it for something). I can also make it build using "--std=c99" (but that makes the undefined behavior mentioned in issue #2 show up, which is why I went with clang). gcc: warning: couldn't understand kern.osversion '14.3.0 gcc (GCC) 4.8.2 Copyright (C) 2013 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
david-given 11y ago
Well, I wrote one in Haskell, so there! (Currently trapped in legal hell. I work for one of those annoying companies that claims ownership of everything I do, even in my personal time, so I have to get it cleared before I can push it to github...) I added some extensions to allow one node to program another; the PROGRAM <dir> opcode resets the node in that direction, and it can then be fed a series of numbers which form the program. Once complete it starts executing. With this, it ought to be possible to program an arbitrary network with programs from a boot ROM attached to a single node at the corner. It would have to propagate the distribution program through the network, which would then in turn propagate the program to the right place and reprogram each node in turn. Because a programmed node wouldn't contain the distribution program any more we'd have to start at the outer edge and work inwards. I do wonder whether it would be possible to get real work done with this. I bet a node could be implemented in a tiny handful of FPGA gates.

FreeFull 11y ago

http://retroforth.org/docs/The_Ngaro_Virtual_Machine.html http://retroforth.org/docs/The_Ngaro_Virtual_Machine.html This virtual machine has been implemented many times in various programming languages. The retro forth download includes most of the implementations.

vanderZwan 11y ago

The game itself I love. But I have some issues with it's implementation. To be specific, it maxes out the CPU even when it's not doing anything. Given that it's supposed to emulate low-level hardware, at very slow speeds, and does not have any demanding graphics, I fail to see why it should do that. (It's something I've seen happening in more games as of late, actually. For example, Desktop Dungeons - a very fun game which has no business demanding anything from my computer since it's turn-based, uses sprites, and barely animated. And yet my laptop heats up as soon as I open the game.) In fact, it's a bit ironic, given that the whole theme of the game is squeezing out performance out of bare metal hardware, and I admit that I'm more annoyed by it for that somewhat irrational reason.

falcolas 11y ago
It's still in early access, perhaps a bug report to the developer would be in order? It doesn't do this on my machine, so it might not be occurring for them.
- vanderZwan 11y ago
  I am running Linux, I have to admit. Could be poor Unity support in that regard.
lfowles 11y ago
This is common with games nowadays. Almost no one throttles the game loop outside of mobile I guess. I've had the same issue with the Analog/Hate _visual novel_ series. My laptop doesn't need to turn into a lapheater for some text....
yoklov 11y ago
IIRC TIS-100 is implemented using Unity, which doesn't really give you a lot of leeway as to when you update and render (e.g. you choose a framerate and it renders and updates your objects at that rate). Admittedly, since most of the time in TIS100 the screen does not change, if it were implemented using a custom engine this could be fixed. For desktop dungeons, I'm not aware of the specifics about that game (though I have played it), but generally, if you're using OpenGL or DirectX to render, repainting only part of the screen isn't an option, so if anything is animated (no matter how slight the animation), you have to redraw the screen every frame. There are exceptions to this (like the mouse pointer, although this requires platform specific code), but not many of them.

cmdrfred 11y ago

Is this a good way to get started with assembly?

markdeloura 11y ago
It doesn't have much in the way of a tutorial yet - this PDF might be a better place to grow your understanding of Assembly Language: http://www.drpaulcarter.com/pcasm/ http://www.drpaulcarter.com/pcasm/
- cmdrfred 11y ago
  Thanks for the tip.

bashinator 11y ago

Zachtronics makes amazing games. This is the same guy who wrote SpaceChem and Infiniminer (the inspiration for Minecraft) http://www.zachtronics.com/ http://www.zachtronics.com/

static_noise 11y ago

MMIX

chetanahuja 11y ago

I've been looking for a simple computer/CPU simulator for kids to play on. Something like this http://thlorenz.com/visulator/ http://thlorenz.com/visulator/ is almost there but it's a bit too complex for elementary/middle school level kids to start on. A game would be even better but the one we're discussing here (TIS-100) is basically designed to confuse and challenge rather than illuminate. Suggestions and pointers are extremely welcome.