A570 OS2.35 - No sound on Audio CD's with 68020

[Br0ther66]

Good morning, first of all thank you for the work and time you dedicate to this.

Not long ago I left you a comment and 'like' in one of your YouTube videos. I am Francisco de Sevilla, Spain. Tomorrow a month ago I updated my A570 to OS 2.35, and the truth is that everything was going wonderfully with my computer. A500 with ROM 2.04 and 3.2.2 ROM switable, 2MB chip MEM, Supradrive 500xp, and M-Tec 68020 accelerator with 4mb Fast Ram 32bit.

Previously with OS 2.30 and this configuration the data CDs were not visible in the Workbench, now with OS 2.35 they work perfectly. The thing is that during this month I was only using data CDs, and today when I went to put a musical CD it turns out that there is no sound.
From there I have made the following checks ....

• Amiga 500 (ONLY 2MB chip mem) + M-TEC 68000 MODE + A570 OS 2.35. Data & Audio CD all is ok

• Amiga 500 (ONLY 2MB chip mem) + M-TEC 68020 MODE + A570 OS 2.35. Data CD is ok, but audio CD no sound. The CD player is that of the environment of the ROM of the A570. Curiously when the 'next' or 'previous' song buttons are pressed very fast, it can be heard that there is sound but during a tiny second fraction. Sometimes fast clicking several times on the Next Song and backing to the first song and the audio can be heard only on the first song, but if we handle it normally nothing is heard on any of the tracks.

• Amiga 500 (ONLY 2MB chip mem) + M-TEC 68020 MODE + A570 OS 2.30. Data & Audio CD all is ok

When I use the hard drive with 68020 it happens exactly the same with the CD Player programs that can be obtained in Aminet I even the original floppy disk of the A570.
I have done the tests by removing the FAST memory of the A570. I have read you that this memory can cause problems, but I have to tell you that with my configuration and OS2.35 the data CDs work correctly with both 68020 and 68000.

I have made a reading to the EPROM that I have programmed and is exactly the same as the file I used to program it. Would there be any solution for this small inconvenience? Except for audio CDs, everything else works perfectly with OS2.35 and 68020.

Thanks again for everything.
All The Best.
Francisco

[Br0ther66]

There is something in 2.35 that causes that the sound not work with the 68020 cache.

SetCPU program v1.60

SetCPU nocache
And again with OS2.35 there is sound in Audio CD's
Working with M-Tec in 68020 mode (4MB Fast Ram), Supradrive 500XP (4MB Fast Ram) with ZuluSCSI RP2040 (SCSI Adapter To SD), ROM 3.2.2 © 2023, Workbench 3.2, and A570 (obviously), with several CDPlayer programs.

The CDPlayer that is in the ROM only works if the 'disable cache' jumper is closed on M-Tec card. Previously with OS2.30 and 68020 it was not necessary to deactivate the cache.

Naturally I stay with OS2.35 and all its new features, and hopefully in the future this tiny problem can be solved.

By the way, with the scsi controller SupraDrive 500XP it is not necessary to apply HDDBOOTDELAY. SupraDrive behaves in a good way with A570 and first appears the animated CDTV Startup Screen. To start the SCSI disc, in this case the SD Card, simply is pressed the escape key .

All the best!

[img]https://i.ibb.co/JQGzg16/A500-01-1.jpg[/img]

[img]https://i.ibb.co/0jLnhJQ/A500-05.jpg[/img]

[img]https://i.ibb.co/qdMpznM/A500-08.jpg[/img]

[img]https://i.ibb.co/0czLYS4/A500-09.jpg[/img]

[C4ptFuture]

Thank you for the extensive report! Glad you were able to pin it down to the CPU caching, as that would’ve been my first suggestion to troubleshoot. OS 2.35 disables CPU caching on startup for 68030 machines, but does not do that for 68020, because no issues were found with 68020 CD-ROM access, however Audio CD playback hasn’t been extensively tested.

So here’s the good news: this looks like a fixable problem for a future CDTV OS ROM release. An option would be to disable CPU caching for 68020 in ROM on startup. Users can then still re-enable it in software once the system is booted up if they want to. (Although I am admittedly stumped why it does work under 2.30 with CPU caching enabled on 68020).

The “less good” news: it’s probably gonna take a while before CDTV OS 2.36 sees the light of day. Probably somewhere during next year. I am currently wrapping up a 2.35 related side project and also refactoring my build pipelines for the CDTV OS resident modules and the CDTV ROM images, which have increased in complexity over time due to having multiple build targets. Cleaning this mess up will allow me to work on 2.36 in a more focused way and keep my sanity. 😉

I will also need to find my Viper 520 so that I can hopefully reproduce the issue you are experiencing on my own setup. BTW, if you have Discord, and want to join the closed 2.36 beta testing once that gets going in the future, please email me on my CDTV Land address (see About page on cdtvland.com) and I’ll send you a personal invite.

Regarding the SupraDrive. The most likely reason why it’s not autobooting from the CDTV Title Screen is because cdstrap currently does not support autobooting from HDDs other than Commodore’s scsi.device and the old SCSI/XT driver in the CDTV OS ROM. That is why oktagon.device and suprascsi.device based HDDs do not autoboot. In fact with the original CDTV OS ROMs you’re stuck forever on the CDTV Title Screen. That is one of the reasons why I have added the force exit option in 2.35 (Escape key), and I am very happy you figured that one out. 😃 (I am planning to add autoboot support for oktagon.device in 2.36 and could add suprascsi.device as well if my current idea of how to add this works as I think it should.)

Finally, wow! That’s a serious sidecar expansion setup you have there. I am particularly interested in the adapter you’re using to add a second Zorro-II port. Where’d you get it? I would love to be able to use both my A570 and Action Replay III cartridge one day!!! 😃

Thanks for using 2.35! 👍

[Br0ther66]

Thank you very much for the explanation, a bit of culture about our Amiga is always good and they are well received.

Even the least good news is great news and the way you are approaching it cannot be better. Thanks for the invitation to Discorg, I will be happy to help in a project like this within my possibilities. I will try to do a parallel installation with another disk and windows 7 or higher. For compatibility with old programs that I prefer, I continue to use the old Windows XP. As soon as I prepare all this I will send you an email to his CDTV Land address.

So, the forced exit in 2.35 with the Esc key something of your invention, is cool! I had read about this on CDTVLand but I came to think that it was a feature of the Commodore rom. Great option then!

The Zorro II duplicator (the red one) is recently acquired, and curiously I bought it in your country. I have another one in green that was made by Alpha-Data in the golden days of the Amiga. I bought the red one here https://gotek.nl/shop-expansion-port-splitter/
Don't let too much time pass because Ed told me that he only had 4 left, although it seems that when he doesn't have stock he orders them to be manufactured again.

And many thanks to you for having created OS2.35 !!!