Atari 5200 emulators running your homebrew VS real 5200

[+Cafeman]

I have mentioned this topic before, and thought I'd bring it up again.

 

First of all, the colors are not accurate on either VSS or Atari800win, though they are usually close. Where both get into trouble is in the $40 to $90 area, I think, where reds look purple and blue's look green and blue's look purple. Maybe some day I can try to help correct this a bit.

 

The other big difference is noticeable when you use a Display List Interrupt and you exceed the time for that scanline.

 

For example, I have a clunky DLI routine in Koffi:Yellow Kopter that contains to many branching CMP compares to determine which DLI you want executed. On some DLI's, I exceed the time and my color changes appear on the NEXT scanline from the one I had intended. I don't think that VSS ever 'catches' this. I did notice in one instance where Atari800win was more accurate -- I noticed that I changed the BG color register in a DLI on scanline 60. On VSS it happened on 60 but in Atari800win it occurred on scanline 61 because by the time I actually changed the register value, the raster had drawn scanline 60 already.

 

So, I need to do some tweaking to get it to look right on the actual machine.

 

Also talking about VSS (and I'm not trying to rip on VSS, I like using it, but developers need to know this kind of stuff), I have noticed that it runs a bit faster on both my home and work machines than on the 5200 itself. I'm running P3's at 750MHz and 1GHz. No biggie there, but I notice that the Windows-based Atari800win runs at a slower and more true speed.

[DanBoris]

The moral of the story is, never trust emulators when you are developing games. They are great for thier debugging abilities, but they are no replacement for the real hardware. Going back and forth between the two (emulation and real hardware) gives you the best of both world.

 

Dan

[OldGuru]

So, I need to do some tweaking to get it to look right on the actual machine.

 

From my experience you can't avoid that phase both on Atari 5200 and on the Vectrex.

In my opinion, Atari 5200's emulators are way better than the ones available for the vectrex. In other words, you can get further in your emulator based development on the 5200's emulators than you can with the Vectrex ones...

 

I believe that this is true for most of the emulators/consoles out there...

Is that true? What about the 2600?

 

OG

[Heaven/TQA]

well... i code since 1998 on pc and atari800win... never tested on real machine but it works... (never heard complains from my friends at www.abbuc.de)...

 

the interesting thing is that even on real machine you have color changes... f.e. my fire routines where done in "red" of course... on my 130xe they were "blue"...so i changed that they were "red" on that machine... but when i saw my demo running on other machine at a demo party it appeared "blue"...

 

but i trust atari800win 3.0 because fox is using this emu heavily so i believe it is 99,9% accurate...and if your colors are not correct...just load another palette....

 

hve

[fox]

I think that one should write programs in a way that they run well in a good emulator (e.g. A800Win PLus 3.0), because emulators are now very popular (and will be more and more). This isn't that hard. If a program runs well in emu, it usually runs well on real machine.

[DanBoris]

This isn't that hard. If a program runs well in emu, it usually runs well on real machine.

 

Unfortunetly, this is not at all true. Actually the reverse is far more correct, if it runs on the real hardware, it should run well on the emulator.

 

The reason for this is that there are certain things that aren't necesarry to emulate to get existing games to work. For example, on a real 5200 if you don't enable the keyboard scanning you won't be able to read the key pads or controllers. On my 5200 emulator, I never emulated this behavior because there was never a time when a game needed to have the scanning disabled, so reading the controllers works on the emulator whether you enable keyboard scanning or not. This tripped up a few 5200 programmers who where developing using just the emulator. This is just one example, there are many others.

 

Dan