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 ikir
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Re: AmigaOS4 will run on BlizzardPPC boards
Posted on 6-Oct-2003 20:26:21
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Elite Member
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Joined: 18-Dec-2002
Posts: 5647
From: Italy | | |
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| Yuppy 
No news about Shark?
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ikir
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Anonymous
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Re: AmigaOS4 will run on BlizzardPPC boards
Posted on 7-Oct-2003 7:15:03
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Poster: ikir Date: 6-Oct-2003 21:26:21
Yuppy
No news about Shark? |
They said they would support it when they recieve a prototype,(in the irc transcript) but what they probably mean is when they get a prototype, they will see if it's worth doing. |
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gnarly
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Re: AmigaOS4 will run on BlizzardPPC boards
Posted on 7-Oct-2003 13:06:25
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Cult Member
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Joined: 16-Mar-2003
Posts: 742
From: Cheltenham, UK | | |
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| Can someone good with acronyms help me? Whats "TLB Lookup"? :)
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Karlos
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Re: AmigaOS4 will run on BlizzardPPC boards
Posted on 9-Oct-2003 14:15:34
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Elite Member
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Joined: 24-Aug-2003
Posts: 4943
From: As-sassin-aaate! As-sassin-aaate! Ooh! We forgot the ammunition! | | |
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| @grarly,
The 603e CPU used on the Blizzard cards does not have all of its memory management units' (MMU)functionality implemented in hardware, unlike for example the full 68030+, 604e etc.
I'm not sure how much you know about MMU stuff, but one of their jobs is to remap areas of memory around so that the real address of a piece of memory/hardware appears to be somewhere else. This is used at the OS level for a lot of things such as kickstart remapping, virtual memory etc.
To implement this remapping, MMUs generally create lookup tables in memory to keep track of stuff. Such tables are usually multi level, dividing the total space visible to the CPU into blocks, sub blocks and pages.
Often used remappings and stuff can be cached on the chip, so finding the real address of a frequently used area of memory is fast. Sometimes however, an address pops up that isn't cached and the MMU has to go and search the tables to find the real address.
One of the things missing in the 603e, but present in 604e and above is the hardware to do the above search. Instead, a software trap has to be installed by the OS that goes and does the search, so it is 'fixable'.
At least, I assume that's what he meant...
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The_Editor
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Re: AmigaOS4 will run on BlizzardPPC boards
Posted on 9-Oct-2003 21:07:44
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Elite Member
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Joined: 7-Mar-2003
Posts: 7629
From: 192.168.0.02 ..Pederburgh .. Iceni | | |
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| Its an Acronymn.
lol
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