Running Demos from a U1Mb/SIDE3 Loader

[andyhants]

I'm trying to work out if the SIDE3 Loader is a viable platform for running .XEX Demos (forgive me Jon I'm not being in any way derogatory). I haven't tried many but the attached Crazy Cars Demo is an example of a Demo that I can run on a simple 800XL base config  - ie just booting to 'Self Test' (all on Altirra with  U1Mb emulation) whereas whatever variant configs I try I can't get it to run from U1MB/SIDE3 Loader. The best I can get is to get to run for a second or two then it crashes. 

 

So my question is two-fold - first can anyone get the attached .XEX running under U1MB/SIDE3 Loader & second more broadly am I being too ambitious expecting the U1MB/SIDE3 Loader to run Demo .XEX images ? 

 

Ideally my aim is to run everything via a Altirra U1Mb/SIDE3 config variants without having to resort to a completely different Altirra config - but am I being unrealistic especially with Demos ? Do I have to accept you have to have a totally non-U1MB/SIDE3 config for running some  / many Atari 8-bit Demos?

 

As ever thanks for any help.

 

BONUSDMO.XEX

Edited March 24, 2023 by andyhants

[Beeblebrox]

My pennies worth. There are many demos I run on u1mb/side3 config. I've only come across a handful that won't run which is (afaik) down to memory mapping conficts (excuse if I've used the wrong terminology) 

 

The excellent rewind and Alley dog demos and the likes of numen, near, cyberpunk, and many others run fine.

[Beeblebrox]

1 hour ago, Beeblebrox said:

My pennies worth. There are many demos I run on u1mb/side3 config. I've only come across a handful that won't run which is (afaik) down to memory mapping conficts (excuse if I've used the wrong terminology) 

 

The excellent rewind and Alley dog demos and the likes of numen, near, cyberpunk, and many others run fine.

Edit: I'll try your attached demo on my setups tmrw. 

[flashjazzcat]

The only reasons a given XEX is likely to fail is if a binary segment happens to overwrite the loader itself (which lives at $700-$A80 or so), or the entire system is unstable and can't read data off the SD card properly. It's certainly not unreasonable to expect XEX demos to run from the SIDE3 loader, but nor is it reasonable to conclude that none work because one doesn't work.

 

I'll test the demo tomorrow, anyway, and find out what the issue is.

 

EDIT: Well, I couldn't wait. The demo for some reason hits $D5FA with an INC instruction, banks SIDE3 ROM into the cartridge space, and promptly crashes. My only advice is to run a different demo.

Edited March 25, 2023 by flashjazzcat

[andyhants]

On 3/24/2023 at 10:07 PM, Beeblebrox said:

Edit: I'll try your attached demo on my setups tmrw. 

Any joy on your setups ?

[andyhants]

On 3/25/2023 at 12:17 AM, flashjazzcat said:

The only reasons a given XEX is likely to fail is if a binary segment happens to overwrite the loader itself (which lives at $700-$A80 or so), or the entire system is unstable and can't read data off the SD card properly. It's certainly not unreasonable to expect XEX demos to run from the SIDE3 loader, but nor is it reasonable to conclude that none work because one doesn't work.

 

I'll test the demo tomorrow, anyway, and find out what the issue is.

 

EDIT: Well, I couldn't wait. The demo for some reason hits $D5FA with an INC instruction, banks SIDE3 ROM into the cartridge space, and promptly crashes. My only advice is to run a different demo.

Ok thanks anyway for trying Jon. My hexadecimal uber-rusty but from what you say its not impacting the $700 to $A80 memory space so I wonder why it works on a plain A800 Altirra config without U1MB/SIDE3 ?? Maybe as you say just writhe that one off & carry on.

[Beeblebrox]

39 minutes ago, andyhants said:

Any joy on your setups ?

Got sidetracked at the weekend. Will try tonight or tomorrow and report back. 

[_The Doctor__]

did you not read the part where he states the demo is hitting a banking register in the SIDEB cart?

If it's happening with old demos that have been around forever it's a problem for the device maker and it's dev's

if it's happening with something you are making from scratch and it works with everything else that's come before, you can keep it exactly as it is and the device simply can be deemed incompatible and/or the dev's might think on the problem and determine if something needs to change to comply with all of what came before.

Even if the device is at fault but can you make it device compliant by changing the use of that register to something else, you might go that route for your new work.

If it's a new work and it doesn't work with the majority of other devices, you work is at fault and should change.

There are a number of things to consider.

 

Edited March 27, 2023 by _The Doctor__

[flashjazzcat]

$D5xx has been the cartridge control area for almost forty-five years, so hitting this area from an XEX whose purpose is anything other than interacting with a specific cartridge imples that the developer is mendacious or clueless (unless someone can educate me as to why this demo needs to write to $D5FA in order to function).

 

All multi-carts require some means of bank-switching, performing parallel IO, etc, and such facilities require control registers in CCTL, period. There'll always be some developer who thinks it expedient to ensure his software won't run on a particular device, of course, but that's their loss.

 

[Beeblebrox]

1 hour ago, Beeblebrox said:

Got sidetracked at the weekend. Will try tonight or tomorrow and report back. 

tested on two U1MB/SIDE3 setups I have with various different setting in U1MB bios just in case. Doesn't run, but I think FJC has since explained why in this instance. Just run one of the other many demos that run fine.

[+Stephen]

5 hours ago, flashjazzcat said:

mendacious

Today I learned a new word.  I must be very low brow, as I find myself often thumbing through a dictionary.  Most of my vocabulary seems to stop post 4 letters!

[_The Doctor__]

That is not the original demo, it has been modified, is it attempting to address existing hardware upgrade in that address space?

Maybe a sound card etc?

[flashjazzcat]

8 hours ago, _The Doctor__ said:

is it attempting to address a non-existent hardware upgrade in that address space

Fixed that for you.

 

Serious point, though: always a good idea to establish that the hardware of interest is present before attempting to write to it, although even attempting to probe for a hardware signature in CCTL (before attempting to write to the hardware) is often enough to completely upset the system anyway if there's something else present. That's why the HDD settings in the U1MB firmware menu don't auto-dim if there's no SIDE cartridge present: the software dare not even attempt to find it until the user explicitly tells it to.

Edited March 28, 2023 by flashjazzcat

[andyhants]

On 3/28/2023 at 2:23 AM, _The Doctor__ said:

That is not the original demo, it has been modified, is it attempting to address existing hardware upgrade in that address space?

Maybe a sound card etc?

Do you have the original version plse ?

[Beeblebrox]

There are loads places to find it potentially.. Fandal's website, Atarionline.pl, guru's website, demo zoo. Also @Mclaneincmight know. 

 

Edit:https://a8.fandal.cz/demos.php

 

http://atarionline.pl/v01/index.php?ct=nowinki&ucat=1&subaction=showfull&id=1680070916

 

https://gury.atari8.info/list.php?src=6&ch=a&th=0

Edited March 29, 2023 by Beeblebrox

[+CharlieChaplin]

Well,

 

the "original" version on the A8 can be found /or/ better is based on the "Big (Atari 8-Bit) Demo" by HTT (Solarsystems was one of their group members): https://a8.fandal.cz/detail.php?files_id=3503

 

From the menu choose "Digi Musix". Note: The released version of the Big Demo was not XF551 compatible, they later released a patch for it. (Think it also does not work on many other drives, that do not check for the disk-lever, like the 1050 does; it should not work with SIO2xyz and most Multicarts, since they don't have a disk-lever. But afaik, the XF551 patch also does not work with every floppy drive, floppy enhancement or floppy emulator. You will see if it works, if you have to flip the disk and loading continues on side B or a load error appears...)  Please check, if the version on the Big Demo disk also uses D5xx.

 

All fileversions of this Crazy Cars demo (that I can find) are packed with Code3 Cruncher it seems, so I guess they are all the same:

https://a8.fandal.cz/detail.php?files_id=185

http://www.atarionline.pl/demoscena/C/Crazy Cars.xex

 

The original version of the music ? Well, someone said its from Jean-Michel Jarre, but I do not know if this is true.

 

Maybe you should try and see if Ethnicolor (this is the digi musix from the Big Demo) works or does not work:

https://a8.fandal.cz/detail.php?files_id=323

 

EDIT: You can also boot diskside B of the Big Demo and it will tell you that this is diskside B and please insert side A and wait a while. Its (still?) checking the disk-lever of the 1050 and since my emulator does not have (or emulate) one, I could wait forever and nothing would happen, while on a real 1050 it would try to load as soon as the disk is flipped/changed, thanks to the disk-lever check...