Casey Ransberger wrote: > Also inaccurate: in their slide deck, they call out that what they've > done is "more like a simulation than an emulation," and that this > approach reduced the amount of code the had tow write, if their > graphs are meaningful, by something like an order of magnitude.
Different groups use the terms "emulation" and "simulation" in slightly different ways, which can cause a lot of confusion. For hardware developers, a simulator is some software that runs on your PC to see if the design is correct or not. An emulator is a piece of hardware that does the same job as what you are designing or some important part of it. For example, a 6502 emulator would be a board with a flat cable and a 40 pin connector which could plug into the socket of an Apple II in place of a real 6502. This board would also be connected to a PC or a logic analyser and would allow you to see what is happening inside the processor while the board is running and even generate memory accesses and stuff like that on a board that is not fully working. For the retro-computing crowd, an emulator is any software that can create a virtual old computer or video game closely enough to run the old software. A simulator is a very detailed emulator which recreate aspects of the original in order to more faithfully run the old software. So an emulator might just grab a byte from the simulated framebuffer and do a simple conversion before sending it to the video card while a simulator might recreate with the original video chip did and then convert the final result into what the modern video card needs. The visual 6502 guys are using this definition. Normally, a simulation is far more work and emulation. But in their case the simulation is so detailed (it goes all the way down to the layout in the silicon) that the code was simple and generic and only needed the very detailed input which they were able to obtain semi-automatically. I said "slightly different", but in a sense these two uses of this pair of terms are almost opposites. -- Jecel _______________________________________________ fonc mailing list [email protected] http://vpri.org/mailman/listinfo/fonc
