Testing emulators with ZX X-MAS '19 Demo

[PeterJ]

Whilst I'm aware that there have been a couple of very useful threads on checking the accuracy of emulators, I wanted to look at testing real world software.

I'm going to start with the ZX X-MAS '19 Demo which was produced by the Abaddon group. It requires ULAplus and AY Sound, and runs on the 48K Spectrum. Most of the errors seem to be related to tape loading so I'm assuming something unusual is being used.

https://demozoo.org/productions/271171/

I tested with ZXSpin 0.7q, along with the latest versions of SpecEmu, ZEsarUX, ES.pectrum, Speccy, SoftSpectrum48, Spectramine, XSPECCY and SPUD.

Thoughts or corrections most welcome.

These are my results:

Edited based on Posts Below

Spin 0.7q - Result - Works Perfectly


ZEsarUX-9.1 Beta 1 - Result - Works, but most be loaded in 'Real Tape' Mode - See below


SpecEmu 3.1b - Result - loads, but ULAplus not activated ***NOW FIXED** See later post


ESpectrum 0.9 - Result - Failed with loading error - Also tried to fast loading off - same result


Speccy 5.5 - Result - Failed with black screen


SoftSpectrum48 15 November 2020 - Result - File loads with fast load turned options off, but issue with ULAplus - See post below

Spectramine 1.03b - Result - Failed with black screen

Xpeccy 0.6.20201026 - Result - Got as far as tape section 4 then had a tape loading error


SPUD 0.2.52 - Results - Loads fine, but ULAplus not enabledt

[azesmbog]

If you test emulators with ULAplus, then it is necessary under equal conditions.
A .tzx file is a kind of testing, incorrect in relation to other emulators. my ZXUno also does not understand this format, give him the racially correct TAP format.
Therefore, if someone from the sources adds a TAP file, then you can test.
I haven't figured it out at all )
And yet - even though SpecEmu launches the file, but on the first screen it writes - ULA Plus not detected.
And the border color is not correct. Judging by the video, it should be bright blue

[PeterJ]

Thanks [mention]azesmbog[/mention],

There are various tools to turn a tzx into a tap so will convert over the weekend.

Spin certainly appears to have the most accurate colours.

[Magnus]

SoftSpectrum 48 does actually load the demo (it takes a while though, because it will only activate flash load when the ROM loader is used). A bigger problem is that the screen turns black as soon as the ULAplus palette is activated. Turning of ULAplus shows the screen again. I'll have to do some debugging to see what happens.

[PeterJ]

Thank you [mention]Magnus[/mention],

As an emulator develoer, does this sort of testing help out?

[chernandezba]

ZEsarUX-9.1 Beta 1 - Result - Failed

Load it as a Real Tape, not a standard tape:







ZEsarUX uses by default fast ("standard") tape loading, by trapping rom calls. It tries to autodetect if a tape needs real tape loading (exactly as a speccy, reading from port FEH), but in this case, the autodetection does not work and you should tell it the tape must load as real tape

[chernandezba]

By the way, compare the colours in this demo running on ZEsarUX with the others you tested... I think all emulators except ZEsarUX and Spin have the wrong colour values...

According to Andrew Owen, one of the ULAPlus creators, ZEsarUX followed the ULAPlus standard perfectly

[Magnus]

Thank you @Magnus,

As an emulator develoer, does this sort of testing help out?

Yes, very much! I'm always looking for problems . Seriously, it is great help because I tend to test the same things over and over, and am not aware of every "difficult" program out there, so it is much appreciated.

To the topic at hand, a quick check tells me that the problem at least for my emulator is that the program won't detect that ULAplus is available and so the palette is never created - thus the black screen. Not 100 % sure about this though.

[PeterJ]

Thank you [mention]chernandezba[/mention],

Original post updated.

[azesmbog]

ZX Uno

The colors are correct. I assure you.
This is a photo from the monitor screen

Spectramine

Border color is wrong
And the colors on the screen are also wrong.

Es.pectrum

[PeterJ]

Was that through converting to a tap [mention]azesmbog[/mention]? If so can you save it do it saves me a job? Cheers.

The Spectramine colour issues look similar to the SpecEmu issues.

Whilst it's good that a tap works for these, tzx should also work (apart from esxdos based systems obviously).

[+3code]

I don't know why, but SpecEmu says "Not ULA+ detected", so the colors in the screenshot are the standard palette.

[azesmbog]

I don't know why, but SpecEmu says "Not ULA+ detected", so the colors in the screenshot are the standard palette.

By the way, I also decided so. Wherever the colors are wrong - ULA + didn't just turn on

Was that through converting to a tap @azesmbog? If so can you save it do it saves me a job? Cheers.

The Spectramine colour issues look similar to the SpecEmu issues.

Well, I already said about the color.
About the TAP file.
no, this is not a conversion.
I reassembled this in SJAsm +
There are two files in the original, I only made the second one, that's enough for testing, but of course it's better to try to convert, it might work out more precisely

[+3code]

I've converted the tzx to tap using ZX-Blockeditor and is the same (in SpecEmu), no ULA+.

[Magnus]

I've found what caused the problem with my emulator. The program detects the presence of ULAplus by reading port FF3B, which when ULAplus is active will return the colour value that was last written to the palette. The odd thing with this demo is that the port is read before anything has actually been written to the palette, so my emulator reported a 0 value, but the program expects the value 1. I haven't seen this specified anywhere but maybe I haven't looked close enough (and apparently other emulators works this way, so I have probably just missed it).

[PeterJ]

I've converted the tzx to tap using ZX-Blockeditor and is the same (in SpecEmu), no ULA+.

Please can you test it in es.pectrum? Thanks

[+3code]

I've converted the tzx to tap using ZX-Blockeditor and is the same (in SpecEmu), no ULA+.

Please can you test it in es.pectrum? Thanks

Begins OK, detecting the ULA+, but then: "Tape Error" : P

[azesmbog]

Begins OK, detecting the ULA+, but then: "Tape Error" : P

That's right, it should be so.
In the first part, Ula plus is simply detected, and its own tap loader is turned on, on which the emulator stumbles. For the same reason, downloading to DivMMC will not work either. My version starts right away from the second part, it may not be entirely correct and beautiful, but it works correctly.
(the hidden part also works correctly by the way)
And yet, I checked SpecEmu with another demo of Ula plus, it works correctly there.

[4thRock]

Looking at the demo screenshot, I don't think I've seen ULA+ and 8x1 attributes used before.
It's brilliant, I really like it!

[Woodster]

Fixed a small bug unsurprisingly related to ULAplus
https://keybase.pub/woodywoodster/spece ... 201120.zip

[PeterJ]

Thanks [mention]Woodster[/mention],

I'm still getting the same issue with that version posted. Is that not the old version 27/02/20?

Thanks

[Woodster]

Thanks @Woodster,

I'm still getting the same issue with that version posted. Is that not the old version 27/02/20?

Thanks

Just edited it. Pasted in the wrong link!

[PeterJ]

[mention]Woodster[/mention],

Sorry, forgot to ask. Is there any chance of an option to hide the toolbar below the menus?

[PeterJ]

Thanks [mention]Woodster[/mention]

Perfect! I will edit the OP.

[Pegaz]

Fixed a small bug unsurprisingly related to ULAplus
https://keybase.pub/woodywoodster/spece ... 201120.zip

Hi Woody, thanks for this update.
Can you please check two ULA artefacts tests (stripes and flash2), which no longer work properly in all versions from the last two years.
The last SpecEmu, which displays them correctly, is from December 2018.