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ross · 05 February 2018, 23:47

I'm patching an old game to make it fully system compliant and found some strange copper behaviour.

After the LoadView(NULL) i used AddIntServer(VBL) to setup my first copper list.. but do not have worked properly.
So after investiganting i've found that COPJMP2 is set to execute a 'void' copper list.
I was expecting total garbage on screen but nothing.. screen clean.
I remembered reading something about the copper that stops in some situation and writing to "dangerous register" (with COPCON zeroed) is one of these.

But what amazed me is that it is used by the system!
So is it considered a feature? or is it just a huge bug?

05 February 2018, 23:47	#1
ross Defendit numerus Join Date: Mar 2017 Location: Crossing the Rubicon Age: 53 Posts: 4,480	Copper HALT I'm patching an old game to make it fully system compliant and found some strange copper behaviour. After the LoadView(NULL) i used AddIntServer(VBL) to setup my first copper list.. but do not have worked properly. So after investiganting i've found that COPJMP2 is set to execute a 'void' copper list. I was expecting total garbage on screen but nothing.. screen clean. I remembered reading something about the copper that stops in some situation and writing to "dangerous register" (with COPCON zeroed) is one of these. But what amazed me is that it is used by the system! So is it considered a feature? or is it just a huge bug?