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Old 24 September 2012, 20:16   #1
mai
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bootblock

I have found inside scene collection a lot of disks, where the disks dont start, when inserting in WinUAE.
I had a look with an hex editor and saw the reason.
Is there any logical reason for this:

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Old 24 September 2012, 21:43   #2
Galahad/FLT
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Quote:
Originally Posted by mai View Post
I have found inside scene collection a lot of disks, where the disks dont start, when inserting in WinUAE.
I had a look with an hex editor and saw the reason.
Is there any logical reason for this:
Try with an Kickstart 3.0+
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Old 24 September 2012, 22:02   #3
mai
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Quote:
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Try with an Kickstart 3.0+
Does not work.
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Old 24 September 2012, 22:04   #4
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Upload a bootblock to the zone and i'll check it out or one of the disks.
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Old 24 September 2012, 22:15   #5
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Yes it's that $68 that causes the boot block checksum to not add up. Set it to 0 and you get the correct checksum.

AmigaOS will only attempt to boot a disk when the checksum is $FFFF FFFF and the first 4 bytes are $444F 5300. Most antivirus utilities should be able to calculate the checksum for you, it's a quick way to find out if this is the cause.
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Old 24 September 2012, 22:22   #6
mai
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Originally Posted by Leffmann View Post
Yes it's that $68 that causes the boot block checksum to not add up. Set it to 0 and you get the correct checksum.
yes, i was aware, but how can this happens, where are many disks with the same $68 value.
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Old 24 September 2012, 22:30   #7
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Good question perhaps all these disks/disk images have been processed with the same buggy tool?
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Old 25 September 2012, 12:28   #8
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Perhaps the scene disks had a custom boot loader on it and the virus killer warned it was a possible virus and 'installed' the disk? (with a incorrect boot crc)
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