Re: C65 on Ebay

> On 2017-11-04, at 17:17, smf <smf@null.net> wrote:
> 
> Some "genlocks" didn't have anything that created a reference signal if the video stopped, so if you no longer fed it a video signal then the amiga locked up. dram won't be refreshed & will lose it's contents, the 68000 wasn't fully static either so that will lose track of what it was excecuting.

I never experienced that. But in the studio you don't (didn't is probably more appropriate today ;-) rely on internal reference generators anyway.

> On 2017-11-04, at 17:29, smf <smf@null.net> wrote:
> 
>> You mean the composite one coming out of the Amigas? Can't confirm either. Never used those for anything. I recall A1k2 used an off-the-shelf encoder chip (by Sony if I remember correctly) but can't say anything about how well it did the job in terms of standard compliance.
>> 
> I mean composite video at all. Composite video inputs on TV's came much later than NTSC and PAL (which was around the 1950's).

I think it was more in the early sixties. Googling might help but it's not much relevant anyway, because...

> Sure we all talk about composite as being NTSC or PAL, but then we talked about amiga's RGB output being NTSC or PAL as well.

... PAL is a method of colour encoding, not transmitting/multiplexing. For those there were other (CCIR/OIRT/...) norms. Therefore composite _is_ / _can be_ NTSC or PAL (or SECAM) compliant and that's correct. Calling Amiga's RGBHV "PAL" or "NTSC" OTOH is definitely incorrect. We used to - incorrectly - call the Amiga output being PAL or NTSC just as a name for the "screenmode" / resolution / refresh rate. Somewhat similar situation is with DVDs, which are/were being labeled as "PAL" or "NTSC", even if there is nothing really PAL/NTSC related on them. I recall I was even minor-correcting some Wikipedia articles on that not so long ago.

> On 2017-11-04, at 18:08, smf <smf@null.net> wrote:
> 
>> Ah, OK - now I get you. Still, I find the claim that "you can't take an NTSC amiga and make it display a valid PAL signal, without modifying the hardware" definitely too broad. I wasn't modifying the hardware. In some cases I wasn't even opening the casing! Although AFAIR those weren't used for NTSC productions.
> You might not have opened the case, but you supplied an alternate system clock and video encoder.

Yes, that's correct. Without supplying the external clock, there would be no genlocking. Without (eventually - we used component workflow wherever possible and as long as possible) external encoding there would be no actual PAL/NTSC encoded signal.

> I see your point as you just bought two pieces of equipment and plugged them together, but doing that bypassed the part of the Amiga that made it "PAL" or "NTSC". It kinda complicates the discussion for the other 99% of users who didn't use genlocking.

Well - but that's the exact point we started from. In home applications where someone might have wanted to connect the composite output from the Amiga to the TV in order to play some, presumably lores, games, the differences you referred to were most probably irrelevant. I have no experience with that form of entertainment but I imagine that in the worst case the picture would have had somewhat skewed aspect ratio. Where timings really mattered was in video production. There Amiga shined from the very beginning, exactly because it was able to produce perfectly timed signal. This was in stark contrast to virtually every other computing platforms of the time and paved way for Amiga becoming the prime choice for DTV, as well as the rapid rise of DTV in general. That's why I "couldn't remain silent" to your claims that "PAL" Amiga can't output signal with NTSC timing ;-)

Anyway - I believe we now both understand where our initial misunderstanding was.

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