Three...Two...One... Breathe.
@Schoenfeld (no trailing ' t', sorry about that..):
It's also funny to see how many people all of a sudden become hardware experts ... Saved 75% in this example, which is NOT representative.
Even though you seem to understand the physics of an intelligent design (hardware/software), you still argue that a 100% cycle exact re-implementation of the Amiga chip set will in fact aid in creating a smaller design. A smaller design is the direct result of an intelligent design process and NOT that of a 100% cycle exact re-implementation. I am completely flabbergasted about you even proposing such a thing when you your self give a perfect example of intelligent design & programming in action (your approach on the comparator issue). Especially as you are so bold as to utter harsh word about it being funny that people all of a sudden become hardware experts just because "hardware' can be produced by writing Verilog. That was a definite 'under the belt' blow. There is no reason to become all personal now Mr 'hardware expert', is there? ;-) Let's just stick to fact and leave fiction be.
I am all for your claim to have people make up their own mind about things. In turn, you should feed them with the correct information, and not just with your way to see the world.
I am glad that you are supportive of my quest to get people to evaluate the information they receive from others. I can assure you that I am trying my best to feed people with all the 'untainted' information that I can get my hands on. From your perspective it might look like I am enjoying a complete Jens Schoenfeld (look, not trailing 't' again, I am finally starting to get the hang of it!) bashing fest; which is not the case. I am not looking to start any personal vendetta or unnecessary problem with you or anyone for that matter. I am however looking to feed people raw facts to the best of my abilities and try and review every bit of information before I post. I am still only human, but then again; so are you! And if there is one lesson that time has taught us, then it's that ALL humans make mistakes. I find it shameful that people (generally that could be classified as loyal followers of which you have many) believe almost everything you say to be fact -period-, even though this isn't always the case. I wish that they all would carefully scrutinize all information perceived. There's no pain in that, is there?
The 68K in an FPGA is necessary to have an Amiga-on-a-chip. Buying the processor is not an option if you're making it a toy - that would be too expensive. Having the processor in the same chip will save a ton of money.
Yes, definitely. An FPGA implementation of the 68k would save something in the region of three euros per board. It amounts to considerable $avings!
Having the 68K CPU inside the chip has advantages that are geared towards getting risk capital:
- less hardware cost
- less problems in getting the hardware (only one manufacturer of silicon)
- less money to spend on patching games (that is: no money!)
You will find that I agree with you on the first two points. I don't quite understand #3 however. Am I correct in assuming that you mean to say that using an original 68k, be it a physical one or it's FPGA re-implementation, will save you on patching games all together in the sense of the games being 100% compatible, or am I overlooking something here?
If you want somebody to spend a seven-digit amount on this project, you have to have something really convincing. The Amiga chip set itself, including memory, might be about as much as a 68000 CPU that you're buying from Freescale, and still, it would not be cycle-accurate: The 68HC000 has slightly different timings than the original 68000 processor on a few instructions. Some games don't like that, they require the exact amount of cycles.
I sometimes ask my self if you know what you are talking about, just like I did when I read the piece of text quoted above. As I recalled it, the 68HC000's functioning was identical to that of the 68000. I looked it up, just in case I was wrong, and was shocked, flabbergasted an quite frankly blown away at the same time, to find that you're telling STORIES again! Check it out:
http://www.freescale.com/files/shared/doc/selector_guide/SG1001.pdf on page number 7, under MC68HC000. The 'additional information' field states; and I quote: "Complete pin and timing MC68000 compatibility with a tenth of the power dissipation".
Aside from the fact that the MC68HC000 listed in the brochure does not come as a DIP, the timing should still be identical (completely compatible) as the packaging has absolutely nothing to do with timings. How nasty is that? You should really get your facts straight Herr Schoenfeld.
Anyway... a more important matter; I am guessing that even if these timing discrepancy would exist, they wouldn't really matter because, and I quote you yet again:
Some people asked if re-implementing the 68K would violate any patents. It would not, because it's running in my own microcode engine. There's a software layer in between that emulates the 68K. The microcode engine is geared towards cycle-exact emulation - most instructions must be slowed down for the processor to be cycle-accurate.
... because of the magical 'microcode engine' and an original 68k emulating software layer. Am I right? Left? Right... patents? I won't even attempt to go there and presume you have all ready done your fair share of homework and lawyer consultations; more than I have done anyway. :-)
May I ask where you are 'sourcing' the 68k FPGA implementation code from? Would it be from opencores.org? I am assuming that you are not going to waste precious development time/money and resources on designing your own 68k implementation from scratch. Oh, and I definitely would like to hear more about your microcode engine if you care to share with me!. I can't quite envision what it is/does and how it works so I would fancy an all-over... I am guessing that more people might just be as interested as I am.
Herr Schoenfeld, I salute you and await you're reply. :-)
@AJCopland:
No wonder everyone gives up and leaves the Amiga if we flame everyone who does anything like this.
If WE flame? So we're flaming now? How sad is that...
@cv643d:
I think it is a bit sad to see so much bashing when a positive new product like this emerges.
I do not really understand what there is to critique, bash or why write technical comments the length of an essay finding faults, discussing technical matters not important to general end users of the product or bashing the developers. Why cant some people just keep a more positive attitude.
I find that it is good to scrutinize everything, and I mean EVERYTHING. Especially when it comes to new products because it generally ensures some form of quality. Even though not all the 'general end users' are interested in- or have the capability to follow up on the 'technical matters', they're still equally important and never cease to exist. And if I didn't have a positive attitude I would probably of never posted anything to begin with. I enjoy the technical tidbits oh so much! :-)
jen-ss (Sander) signing off. Thanks!