Re: [hatari-devel] "SECAM" STE's

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 05/11/2024 à 13:28, Adam Klobukowski a écrit :
> Source of this information is Jakub Kruszon Zawadzki, also known as 
> Acid Maker known for a lot of great demos and some hardware (SIO2PC, 
> Medusa)
>
> Jakub owns a french STE without a TV modulator. I'll refer to it 
> as SECAM STE (but I do not know if it is really SECAM related or just 
> Tramiels having a stock of clock oscillators to use). It has a bit 
> different main clock which causes some timing sensitive effects to 
> fail. Jakub did some measurements and come to following measurement:
>
> #define ATARI_STE_SECAM_MCLK 31922046                        /* 
> CPU_Freq = 7.9805115 MHz */
>
> Which he used to test modified Hatari build against his latest demo 
> https://demozoo.org/productions/355416/ that has a number of 
> overscan/colorfull effects and supports STE SECAM timings.
>
> Attached are test programs written by Jakub.
>
> Also I and Jakub think it would be nice to have a  switch in Hatari to 
> be able to switch between PAL/NTSC/SECAM models.

Hi

thanks for this report.

Could you elaborate more on which effects are failing ? I'm asking 
because I also have some french stf and ste and I never saw any problem 
running demos that were not specifically targeted for "secam" machines 
(as opposed to PAL).

From a quick search I see that germany used PAL standard instead of 
SECAM and nonetheless demos made on german STF/STE are working fine on 
french secam STF/STE (at least they work the same).

When coding fullscreen, there's no PAL/SECAM difference that I know , 
it's about 50 Hz vs 60 Hz.

Or maybe it's just Jakub's french STE that has some hardware issue and 
demo would work fine on others STE ?

Unfortunately my STE has no harddrive, so I can't run "The Coders' Guide 
To The Demoscene". Maybe Jakub could provide a simple demo program that 
can be run on a plain STE from floppy and that shows these issues (as 
other people here also have STE, it could be tested on PAL and SECAM STE)

So, I'm not against looking at this in Hatari's code, but I would need a 
small reproducable program that shows the issue first.

Nicolas