Batman Returns Sega/Mega CD - Screen stays black with option "Plattform only"

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What steps will reproduce the problem?
1. Choose gametype "Plattform only" in the Options menu
2. Start the game

What is the expected output? What do you see instead?

The game should start with the first plattform level.
Instead the screen stays black and the main menu music plays.

What version of the emulator are you using (official, SVN revision,...)?
1.7.3.

Tried both, the US Version (from the net) and the EU Version (ripped from my 
own copy). I've attached the cue file from my EU Version. Ripped with IMGBurn.

Original issue reported on code.google.com by gora.pat...@gmail.com on 9 Dec 2012 at 8:11

Attachments:

• BATMAN_RETURNS.CUE

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Original comment by ekeeke31@gmail.com on 9 Dec 2012 at 10:09

• Changed state: Accepted
• Added labels: Type-Defect, Priority-Medium, SCDEmulation

[GoogleCodeExporter]

Will need to investigate about it.
In the mean time, if you could tell me if this in ever worked (in 1.7.0 or in 
1.7.1), this could help figuring what is causing this.

Original comment by ekeeke31@gmail.com on 9 Dec 2012 at 10:18

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just tried it in 7.0 and 7.1 and in both it's broken already.
Just tried both isos with fusion 3.64 and it just works fine.

Original comment by gora.pat...@gmail.com on 10 Dec 2012 at 5:14

[GoogleCodeExporter]

It appears this was caused by a bug in the game... and my implementation being 
not robust enough against this kind of bug.

For the record, MD side was attempting to write to a read-only register and 
this ended up corrupting the register on SUB-CPU side. Ignoring writes to 
read-only registers on MD side fixed it.

Fixed in r757

Original comment by ekeeke31@gmail.com on 10 Dec 2012 at 7:26

• Changed state: Verified