GARTHWILSON wrote:
That's something that has only human I/O, so the difference hardly shows up there. However, it definitely cannot take the place of the emulated computer where the latter has particular ports, pinouts, voltages, timings, signaling protocols, etc.; so it is a very narrow, limited view of emulation that ignores the reality of other fields of computing. My own use of the 65xx has almost no human I/O.
All interesting perspective.
The Commodore 64 has the same BASIC I/O ports for Joysticks and RF Television output as the Atari 2600.
The same Cartridge port is not present, but GameLoader emulation solves this by dumping and recompiling the source which is also necessary to add Commodore graphics to Atari games.
I worked on the Development Team for the Retron77 emulated Atari console which inspired this idea by including a cartridge port that dumps the cart ROM into the emulator.
GameLoader emulation also includes a soft ANTIC chip that I designed. All the advanced Atari 2600 demos being emulated have the soft ANTIC chip too, but it is only a virtual chip with no hardware behind it like the Atari 400/800/5200 so perhaps it is more concept emulation of Display Lists.
I consider both the soft ANTIC and the soft TIA implementation on the C64 close emulation, since Atari 2600 demos run unchanged with precise timing.
I enjoyed your article on 6502 interrupt variations.
I was surprised to see FluidCity, one of the fastest Atari 2600 games, jitter on the Rectron 77 with an intermittent screen roll that does not happen on the real hardware. An interrupt from the Linux OS running the emulator is doubtless responsible. I saw the same problem developing the C64 Atari emulator and initially used an NMI to stop other interrupts.
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Load BASIC from tape on your Atari 2600:
http://RelationalFramework.com/vwBASIC.htm