XCopy2 No virus Bootblock.

redblade · 07 May 2006, 00:55

Hi guys I'm having trouble dissassembling the xcopy bootblock.

I've uploaded what I've done so far to the zone.

What I'm trying to do is get it to run on AGA as a exe instead of a boot block.

I'm mainly having trouble trying to find how much memory needs to be allocated by using blk.b in the source.

I realise that you can't use blk.b on the boot block because of the 1k-Dos-Checksum-Filesystem barrier.

I would like to know how big _BitMap is and also a bit more explanation with $7ee80, and how you calculated / figured it out.

Thanks, should take experts hopefully less then a minute to figure it out.

Galahad/FLT · 07 May 2006, 16:43

I would assume that blk.b is the same as dcb.b

Copperlist = $7ee80
Bitmap, 2 colour, single plane = $7ef00
Standard lowres 2 colour single plane 320 wide, 256 height
End of chip ram on a standard 512k chip ram machine is $80000 so the bitmap cannot exceed that.

So $80000-$7ef00 = size of screen to allocate

NOB · 07 May 2006, 17:20

blk.b is a Seka directive (IMHO seka/asmone only)
dcb.b is a Devpac(and other assemblers) directive.

redblade · 08 May 2006, 02:09

thanks for the help guys.

I'll try and rip into it again.

now to leeach aga.guide

07 May 2006, 00:55	#1
redblade Zone Friend Join Date: Mar 2004 Location: Middle Earth Age: 40 Posts: 2,130	XCopy2 No virus Bootblock. Hi guys I'm having trouble dissassembling the xcopy bootblock. I've uploaded what I've done so far to the zone. What I'm trying to do is get it to run on AGA as a exe instead of a boot block. I'm mainly having trouble trying to find how much memory needs to be allocated by using blk.b in the source. I realise that you can't use blk.b on the boot block because of the 1k-Dos-Checksum-Filesystem barrier. I would like to know how big _BitMap is and also a bit more explanation with $7ee80, and how you calculated / figured it out. Thanks, should take experts hopefully less then a minute to figure it out.

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07 May 2006, 16:43	#2
Galahad/FLT Going nowhere Join Date: Oct 2001 Location: United Kingdom Age: 50 Posts: 9,020	I would assume that blk.b is the same as dcb.b Copperlist = $7ee80 Bitmap, 2 colour, single plane = $7ef00 Standard lowres 2 colour single plane 320 wide, 256 height End of chip ram on a standard 512k chip ram machine is $80000 so the bitmap cannot exceed that. So $80000-$7ef00 = size of screen to allocate

07 May 2006, 17:20	#3
NOB Zone Friend Join Date: Aug 2005 Location: Germany Age: 52 Posts: 424	blk.b is a Seka directive (IMHO seka/asmone only) dcb.b is a Devpac(and other assemblers) directive.

08 May 2006, 02:09	#4
redblade Zone Friend Join Date: Mar 2004 Location: Middle Earth Age: 40 Posts: 2,130	thanks for the help guys. I'll try and rip into it again. now to leeach aga.guide

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