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General Category => Games => Topic started by: DanyPPC on 15:31, 12 August 18

Title: [Enlightment - Druid 2] 6128+ Fix ?
Post by: DanyPPC on 15:31, 12 August 18
Game tested with success on CPC 464+, but it doesn't work on 6128+
After the loading screen only black or reset system.


Is there a fix for CPC6128 Plus ?
Many thanks
Title: Re: [Enlightment - Druid 2] 6128+ Fix ?
Post by: arnoldemu on 16:48, 12 August 18
Game tested with success on CPC 464+, but it doesn't work on 6128+
After the loading screen only black or reset system.


Is there a fix for CPC6128 Plus ?
Many thanks
The original doesn't like the multiface 2. So make sure that is disconnected.
The crack uses CrownCruncher and it looks like it expects some values in memory to be initialized but this is not always true.
EDIT: Correction. I think the CrownCruncher is ok.
Title: Re: [Enlightment - Druid 2] 6128+ Fix ?
Post by: arnoldemu on 17:05, 12 August 18
The original doesn't like the multiface 2. So make sure that is disconnected.
The crack uses CrownCruncher and it looks like it expects some values in memory to be initialized but this is not always true.
Do this before running druid2:

poke &af73,0:poke &af74,0

does that help?
There appears to be some bug where it's setting a palette colour.
Title: Re: [Enlightment - Druid 2] 6128+ Fix ?
Post by: DanyPPC on 19:34, 12 August 18
WoW !  ;)


Now it works very well, no problem.
Many thanks !
Title: Re: [Enlightment - Druid 2] 6128+ Fix ?
Post by: arnoldemu on 20:18, 12 August 18
WoW !  ;)


Now it works very well, no problem.
Many thanks !
Great.
What happens in the bug: It looks like the code wants to change the colour in the palette. It reads data from these two addresses adjusts it and writes it out to set the colour. If the data is not initialized then in some cases it will change the rom configuration or the ram configuration. On any machine with extra ram this could cause a crash because the code covers the region from &4000-&7fff and changing the ram configuration will switch it out.

It's possible, but I haven't confirmed that because the ram chips on the Plus machines are 4-bit instead of the 1-bit on the cpc, then the value of the ram after power on could cause the problem to happen more regularly - the pattern of the ram after power on is in a certain state.


Title: Re: [Enlightment - Druid 2] 6128+ Fix ?
Post by: DanyPPC on 20:58, 12 August 18
Thank you for the exhaustive technical explanation  ;)