Moderator: Moderator Team
I have noticed that GODS intro music theme sounds wrong on NTSC Ataris.
I know GODS was a PAL release, but was there an NTSC version ever released? Is it somehow possible to make it sound correct on NTSC machines?
This is all down to the TOS version being used, and easiest way that i know to get Pal software running correctly on Ntsc machines, without a rom changer board is to use a software version. I have a bootable version of TOS 1.04 on floppy, which stays in memory till a cold reset takes place. You will need to have 1 meg of ram, as it obviously takes 256kb or so of usable ram away, but Gods works fine on a 512 machine. I have tested this under emulation using a USA TOS Version and it changes the machine to 50hz and it boots God with perfect timing of the sound etc.
Here's a link for the software https://we.tl/t-ccvMtVdhbz
The funny thing is that GODS.MOD (from the Amiga version) uses CIA timing and not VBLANK timing.
Also the play routine on the ST uses Timer A so it should be independent of the screen refresh rate.
I only tested it with the version on Automation 476A/B. No 50/60Hz toggle on the menu.
Hardware: Cumana CSA 354, Ultimate Ripper, Blitz Turbo, Synchro Express II (US and UK Versions).
I also have several MiSTer setups, which provide a wonderful AtariST line implementation, and I am lately addicted to the recently released HatariB core for RetroArch because of the shaders and low input lag using Vulkan on Linux.
On both the 520STFM and the Pi4 running the HatariB core, I would prefer a version of GODS with correct music.
On the MiSTer it's not a problem because it implements both PAL and NTSC machines.
The only way to fix this would be to run the tracker routine off some other timer than the VBL and program the timer to run at 50Hz. Not impossible, it's just nobody has done it yet.
Depending on what needs to continue running in the VBL, running the tracker routine under a 50Hz timer can be complex.The only way to fix this would be to run the tracker routine off some other timer than the VBL and program the timer to run at 50Hz. Not impossible, it's just nobody has done it yet.
If the VBL is executing timing-sensitive code (such as setting the color palette, arming timer B...) then the VBL must not be interrupted by the timer running the tracker routine.
The naive solution that comes to mind is to mask the timer in question at the start of the VBL and unmask it at the end.
But there is always a window after the VBL interrupt has been triggered and before the timer is masked, making it possible for the tracker routine timer to interrupt the VBL...
I had to solve this problem for my enhanced crack of Son Shu Shi, in order to be able to play the music modules at 50Hz on NTSC or VGA machines.
It was a lot of "fun"!
The solution was to detect on the fly whether the timer had preempted the VBL and delay its execution until the end of the VBL (which in reality meant reversing the priorities of the VBL and the timer "by software").
- Atari Super Hero
- Posts: 697
- Joined: Thu Jun 06, 2002 12:01 pm
- Location: Montreal, Quebec
But on RetroArch/HatariB on Wayland, that doesn't quite work because RetroArch on Wayland can't change videomode on the fly, so what I would need for that is a version playing the music correctly without setting a 50Hz mode.
But its not that important because I am using a 50Hz configuration on RetroArch now anyway
That's exactly what GGN understood, hence his answer about the technical solution of running the tracker routine using a specific timer ("outside" the 60Hz VBL).what I would need for that is a version playing the music correctly without setting a 50Hz mode.
And I was following up his answer because this approach (which I implemented for the crack of Son Shu Shi) is a technical challenge that's more complicated than it sounds (see my previous answer).
Even if it's highly unlikely that anyone will implement this solution for GODS, it's still very interesting to talk about it in this thread
I'm not sure, Astronut was someone Wurzel knew but I never met or even talked to them myself. I think they were a young guy who was supplying a few originals to Wurzel and maybe interested a bit in coding/cracking. They would have been from SE England, most likely Kent or Essex, yes.