Copper Demo Issue

[DaveInFL]

Still all very new to this so please bear with me.

So I entered the copper demo from the ASPG and when I run it from ASM-One it works fine.

I've also been following @mcgeezer and his video tutorials, of which the first was setting up an environment which allows to edit in a more modern IDE (I am using Atom) and to use vasmm68k_mot to compile the assembler source and create an exe file that can then be executed from WB.

I initially tried this with the ASPG's 2 bitplane scroll demo and it worked fine. But for some reason when I try this of the copper demo it does not display the 3 colours at all, it just shows the WB screen. I can see the program is working as I have to click the mouse button to exit. So, what's going on and why won't it work except from ASM-One?

Here's the command I am using to create the .exe file.

./vasmm68k_mot -m68020 -kick1hunks -Fhunkexe -o ~/Documents/EMUs/Amiga/Utils/Classic-WB/PC/code/${filenoext}.exe ./${filename}

[kamelito]

I guess it is a different problem than the one you get there ? http://eab.abime.net/showthread.php?...highlight=Aspg

[DaveInFL]

Originally Posted by kamelito

I guess it is a different problem than the one you get there ? http://eab.abime.net/showthread.php?...highlight=Aspg

Well, good point, and maybe not. I am running the .exe file from Classic-WB using an A1200 emulation. There's no graphics card selected but perhaps the Classic-WB 3.1 is not a native screen mode? Maybe that is why?

[DaveInFL]

Ok, so after doing some testing it definitely has something to do with the Classic-WB 3.1 install. What though I have no idea.

Guess I need to do a straight, clean WB3.1 install to test these assembler programs out on.

[DaveInFL]

Since it is probably down to the screen mode, what is the assembler call to set the screen mode to (for example) Pal 320x256 or 640x256 so that the code contains the code to set the correct screen mode so that it runs no matter what.

Does setting the screen mode have something to do with DIWSTRT and DIWSTOP? Setting these to be 320x256 (I know it's not that simple) would result in setting the screen mode to what it needs to be so that the code runs, even if I run it from Classic-WB which has some pretty hi-res modes? Or is there some system call that can simply set the screen mode to one of the standard Amiga modes?

[StingRay]

Originally Posted by DaveInFL

Since it is probably down to the screen mode, what is the assembler call to set the screen mode to (for example) Pal 320x256 or 640x256 so that the code contains the code to set the correct screen mode so that it runs no matter what.

You need to flush the view (graphics.library), for this you need to obtain the current view, clear it and then perform two WaitTOF() calls.

You can see how this is done in my startup code: https://github.com/MK1Roxxor/MiniSta...ster/startup.i
Relevant routine is ".DoView".

[DaveInFL]

Originally Posted by StingRay

You need to flush the view (graphics.library), for this you need to obtain the current view, clear it and then perform two WaitTOF() calls.

You can see how this is done in my startup code: https://github.com/MK1Roxxor/MiniSta...ster/startup.i
Relevant routine is ".DoView".

Appreciate that, but at the level I am at (super beginner) that is way above my head.

[roondar]

A way to fix most of this is to use available startup code made by expert developers. There's a number of these startup routines available. StingRay offered his, which undoubtedly works very well. Personally, I use the startup code by Photon (it can be found here: http://coppershade.org/articles/More!/Downloads/ under "Photon's Ministartup.S"), which has worked really well for me.

There's some more options, but at any rate I'd recommend against making your own

[phx]

Originally Posted by DaveInFL

There's no graphics card selected but perhaps the Classic-WB 3.1 is not a native screen mode? Maybe that is why?

No. The main reason is that you turn off Raster, Copper and Sprite-DMA and load your copper list without reenabling Copper-DMA after that. I would recommend at least

move.w #$8280,DMACON(a5)

after setting COP1LC, besides loading a NULL-View followed by two WaitTOF(), as noted by others.

And please remove the

clr.w COPJMP1(a5)

line. The copper list pointer is loaded automatically from COP1LC when a new frame starts. So COPJMP1 has no effect, besides potentially triggering a chipset-bug when the Blitter is busy at the same time.

Also never use CLR on chipset registers (I/O registers in general), if you want your code to run on 68000 without side effects (read/modify/write cycle, due to 68000 bug).