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Author Topic: 256k Debug Bios.  (Read 156 times)

Cheerio

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256k Debug Bios.
« on: March 01, 2003, 07:24:00 PM »
not unless you want too wink.gif
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xMonoxide187x

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256k Debug Bios.
« Reply #1 on: March 01, 2003, 08:40:00 PM »
What he means is no, unless its a Homebrewed "Debug" BIOS that has some of the same functions.  wink.gif
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Cheerio

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256k Debug Bios.
« Reply #2 on: March 01, 2003, 11:38:00 PM »
musta not been thinking, i meant "not unless you want to make one wink.gif"
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xMonoxide187x

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256k Debug Bios.
« Reply #3 on: March 02, 2003, 08:59:00 AM »
I was pretty sure the Flubber Ani was stored elsewhere and the BIOS just initiates it to run, but, I could be wrong.

And Complex's Debug BIOS is 512k, but most "places you can get it" have files that are looped to 1024k or "1.3mb" to fit onto 1mb chips.
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dankydoo

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256k Debug Bios.
« Reply #4 on: March 02, 2003, 10:22:00 AM »
QUOTE (xMonoxide187x @ Mar 2 2003, 04:59 PM)
....
And Complex's Debug BIOS is 512k, but most "places you can get it" have files that are looped to 1024k or "1.3mb" to fit onto 1mb chips.

What the heck?


1.3 MB is the size of the kernel after it is decompressed into memory, it has nothing todo with the overall size of the bios image...(include as Undead said the boot loader, xcodes, decoy, and kernel...compressed).
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xMonoxide187x

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256k Debug Bios.
« Reply #5 on: March 02, 2003, 02:31:00 PM »
Wow, I read that wrong, then posted something out of my ass. Sorry, I shouldn't come on here right after I wake up.

I think I figured that guy was talking about the BIOS and not the kernel, and he just rounded up from 1024k as most people think 1000k = 1mb. But, that wouldn't even make sense, so, nevermind.

Either way as said before, the DEBUG BIOS is a 512k BIOS, no matter how much the kernel is compressed.
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xMonoxide187x

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256k Debug Bios.
« Reply #6 on: March 02, 2003, 03:14:00 PM »
I'm on a roll today. wink.gif

But of course I meant MB.
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dankydoo

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256k Debug Bios.
« Reply #7 on: March 02, 2003, 04:38:00 PM »
QUOTE (xMonoxide187x @ Mar 2 2003, 10:31 PM)


Either way as said before, the DEBUG BIOS is a 512k BIOS, no matter how much the kernel is compressed.

This limitation is probobaly imposed by the CAB compression algorithim....using a better lossless compression could yield a smaller compressed kernel, and maybe the extra kb needed to get it to fit, but then again, who really cares......
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BenJeremy

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256k Debug Bios.
« Reply #8 on: March 02, 2003, 04:49:00 PM »
QUOTE (dankydoo @ Mar 2 2003, 08:38 PM)
QUOTE (xMonoxide187x @ Mar 2 2003, 10:31 PM)


Either way as said before, the DEBUG BIOS is a 512k BIOS, no matter how much the kernel is compressed.

This limitation is probobaly imposed by the CAB compression algorithim....using a better lossless compression could yield a smaller compressed kernel, and maybe the extra kb needed to get it to fit, but then again, who really cares......

and the end result is that if you are serious about development, get a mod capable of handling at least a 512k BIOS.
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Mage

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256k Debug Bios.
« Reply #9 on: March 02, 2003, 10:48:00 PM »
hm if you know the entry point of the bios and the state of the xbox on boot, couldn't you have a bios that loads, and just replaces itself with the debug bios in memory then jmps to it?  So you could store the real bios on the hard drive...so that loader bios would have to be able to at least access the hard drive.  A lot like how the dos loader for linux works.  
But yeah it'd make sense to get a chip that supports >256KB if you're serious.

EDIT:  After looking quickly over the cromwell cvs, if such a method is possible that might be the best bios work off of for such a project.
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Mage

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256k Debug Bios.
« Reply #10 on: March 02, 2003, 11:44:00 PM »
Yeah, it is one of those ideas that people will just think, "get a chip that can support it."
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Cherry

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256k Debug Bios.
« Reply #11 on: March 03, 2003, 04:41:00 AM »
I can do this for 1.0 boxes, I just haven't had the time to do it yet. It requires rewriting of the bootloader, and I am unfortunately extremely busy, so haven't even had a chance to look into it.

I don't think it's going to be possible to do a bual boot, or even a version for 1.1 boxes, because too much of the 256K is taken up by data that *has* to be there in order for the 1.1 box to boot.
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dankydoo

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256k Debug Bios.
« Reply #12 on: March 03, 2003, 11:08:00 AM »
QUOTE (Mage @ Mar 3 2003, 06:48 AM)
hm if you know the entry point of the bios and the state of the xbox on boot, couldn't you have a bios that loads, and just replaces itself with the debug bios in memory then jmps to it?  So you could store the real bios on the hard drive...so that loader bios would have to be able to at least access the hard drive.  A lot like how the dos loader for linux works.  
But yeah it'd make sense to get a chip that supports >256KB if you're serious.

EDIT:  After looking quickly over the cromwell cvs, if such a method is possible that might be the best bios work off of for such a project.

this seems very doable, especially since this is essentialy the way that cromwell xbe boots itself, This would be great to be able to select a bios on startup, I have a strange feeling this will be one of the next big bios advancements from either evoX or xecuter....but hey, that's just me, and Im a speculatory bee bop a shoo bop.........I have no idea why i just put that...


dankydoo
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xMonoxide187x

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256k Debug Bios.
« Reply #13 on: March 03, 2003, 05:40:00 PM »
QUOTE (Cherry @ Mar 3 2003, 01:41 PM)
I can do this for 1.0 boxes, I just haven't had the time to do it yet. It requires rewriting of the bootloader, and I am unfortunately extremely busy, so haven't even had a chance to look into it.

I don't think it's going to be possible to do a bual boot, or even a version for 1.1 boxes, because too much of the 256K is taken up by data that *has* to be there in order for the 1.1 box to boot.

That would definetly be cool if you got around to it. I'd use it, just because that would save me from screwing up the flashing of my TSOP or spending more cash on an X2 PRO to put on my Debug Xbox...which I'm still waiting for. dry.gif
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Nailed

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256k Debug Bios.
« Reply #14 on: March 06, 2003, 03:43:00 AM »
QUOTE (dankydoo @ Mar 3 2003, 12:38 AM)
QUOTE (xMonoxide187x @ Mar 2 2003, 10:31 PM)


Either way as said before, the DEBUG BIOS is a 512k BIOS, no matter how much the kernel is compressed.

This limitation is probobaly imposed by the CAB compression algorithim....using a better lossless compression could yield a smaller compressed kernel, and maybe the extra kb needed to get it to fit, but then again, who really cares......

Actually cab compression is quite good, although proprietary.
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