107 replies to this topic

[Wonko the Sane]

Well, everyone has his own "mental" map and his own way of representing it.
The steps (and the way I represented them) are anyway a simplification.
In my mental map the things in parenthesis mean that - as an example - in:

In other words, in "plain", single boot installs:
....
....
....
BIOS->MBR->PBR->NTLDR->(BOOT.INI)->NTDETECT.COM->"Switch"->Other files->OS booted

The BOOT.INI has not an actual use in the booting, since it contains a single entry (and BTW if you installed to First Active partition of first disk in a directory named \WINNT\ - up to 2K - or \WINDOWS\ -XP and 2003 - you can even remove BOOT.INI alltogether).

About this:

Please specify in the top row what was on your mind. For example, I can figure out that the second column is "type of medium", is the 3rd "type of emulation", ...? I can see that it is a classification of some kind, but I can't make out how it is classified.
When I get that, I will make a mind map of it. That illustrates this kind of concept in less space and is more readable. As soon as you're finished of course.

it's the same, about different mental maps, it is a graphically awful (I do suck at graphics) representation of a "tree", the fact that some "branches" are in the same column doesn't really mean that all items in the same column are in the same category.

It should look more like a genealogy tree (but in a genealogy tree you have generations as "columns"), this tree is more like a real tree, where branches not necessarily sprout at exactly the same height .....
...my idea is more like this:
http://www.ladell.ec...reediagram.html

I will review the other suggestions.

I put the ">=7.x" because grub4dos could directly chainload only those IO.SYS, last time I checked.
(and then we would go for the distinctions and similarities with IBM DOS and it's files: IBMBIO.COM vs. IO.SYS and between IBMDOS.COM vs. MSDOS.SYS .... the idea was to make a simplified "concepts in a nutshell" and NOT a treatise on how every OS in the world boots and works )

For the record there are also another TWO distinctions between DOSes <7.x:

• The kernel is actually TWO files, IO.SYS and MSDOS.SYS AND IO.SYS must be first file in the filesystem (compare with BOOTPART usage and commands)
  http://www.winimage.com/bootpart.htm
• The ONLY filesystems supported are FAT12 and FAT16

and those >=7.x:

• The kernel is "monolithic" (MSDOS.SYS is just a ".ini" file) and there is no *NEED* for IO.SYS to be the first file in the filesystem (use anyway some common sense, you cannot put it in a very high address of it on "BIG" drives)
• Filesystems supported include, besides FAT12 and FAT16 also FAT32

Maybe I expressed myself wrongly.

The PBR "normal" boot code loads one (or more) programs.
In the case of DOS (still >=7.x) and of FreeDOS, it loads directly the kernel.
In most other OSes it loads a loader, that later loads the kernel.
What I was tryng to convey is that in DOS loader and kernel are the same single file.
The above is the ONLY distinction I wanted to point out, there are MANY more limitations and small differences, but again, the idea was to make a quick "reader's digest", if you really want to know the whole story, then you'll have to read many, many books and articles and learn a lot of more things.


Wonko

[LeMOGO]

@wonko

I get that it is a matrix that is a bit of the pain to put in 2 dimensional view. That is exactly why we are having problems in the learning process. The more I read, the more I learn, the more things "branch" off. I need to bring all this in focus somehow and see how it can be simplified. Your post helped me a great deal in that as you can see from my attempt in the table above.
Even if the branches don't sprout at the same height, they sprout at different heights, and do sprout. I'm trying to "group" these heights in some logical fashion (sprouting).

Lets try to simplify it irrespective of OS specificity:

BIOS > drive       > OS

       mbr > pbr   >loader > kernel > interface

I realize that sometimes the "drive" portion above is os specific (meaning that the software on the mbr for example must work a specific "os way"). But at least I get an understanding from this simplification.

Next, I realize that grub4dos can take care of the "drive" part. The loader may or may not be necessary at that point, based on the OS and the fact that grub4dos itself could serve as the loader.

Once I reach at the "OS" stage, the rest should work provided I have fulfilled the requirements in the pre-OS boot phase (i.e. map, mem...).


So, I can break down your "step 1"

booting (real mode) involving BIOS+MBR(+hidden sectors) and possibly PBR/bootsector, then filesystem and initial OS loader/system file

in two broad steps:

BIOS > drive

I want to focus ONLY on the drive part for now.
So I have drive:

mbr > pbr

In both cases, there is a reserved space at the beginning of the disk (regardless of the type).

MBR(+hidden sectors)

In the case of MBR, the very beginning of the drive, things are conventionally limited to 512bytes (legacy). Some utilities such as fbinst reserve a larger portion(+hidden sectors).
Essentially, the role of this section (MBR+hidden sectors) is to hold the table of contents of the drive ( which in turn holds the portion of the drive that is marked as the section to go to next - the active primary partition), and some software. So, on the MBR, there are 2 things:

• the partition table: a list of the subdivisions on the drive.
• the bootloader: a software that parses the list, finds the location to go to, loads the beginning of that location, and turns control over to what is loaded.

Our interest is in the software that resides here. Regardless of the OS, "some" software resides here. So that is one column.

The next one is the pbr.

...get my drift?
lets say "drive" is the root of the tree as you illustrated it. By growing from there and doing what you did with the usb tree, we can have categories that are not OS dependant. THEN, we can see what OS uses what portion and what method skips what portion.

From my explanation above, you can see that I'm beginning to understand. I just don't have a full grasp yet, but I'm sure the "table" will plug all the holes.

Again, thank you for your time. I may sound repetitive, but I mean it. I really appreciate it.

Edited by LeMOGO, 20 January 2011 - 09:39 PM.

[LeMOGO]

@wonko
Concepts like this that are multidimensional are best illustrated through mindmaps because they are exactly the tree that you are referring to, but inverted.
I will make one of the whole concept once I feel I have the needed components.

You can change the look and feel of it, but here is a sample:

Edited by LeMOGO, 21 January 2011 - 12:24 PM.

[Wonko the Sane]

@wonko
Concepts like this that are multidimensional are best illustrated through mindmaps because they are exactly the tree that you are referring to, but inverted.
I will make one of the whole concept once I feel I have the needed components.

You can change the look and feel of it, but here is a sample:

Yep

There are quite a bit of free software to create that kind of stuff:
http://freemind.sour...x.php/Main_Page

Now, a good idea would be to start a new thread and stop this OT on the fbinst thread....
...actually it may be better if you create TWO of them (one related to the "USB devices" and one related to the booting steps and/or "Switch").


Wonko

[LeMOGO]

@wonko

OK.
Let's do that:

• USB booting: how to create a UFD that will boot on most machines.
• The boot process: a step by step approach to booting.

Should I create individual topics for the bullets in the second thread?
How can I monitor the thread for posts?
Is it possible for me to summarize the posts on top as people contribute, and create a usable illustrated document?

Thank you.

Edited by LeMOGO, 22 January 2011 - 01:54 AM.

[LeMOGO]

I found the watch topic button.

[Wonko the Sane]

Should I create individual topics for the bullets in the second thread?

Naah, it would obstacle the interconnectedness of all things....

How can I monitor the thread for posts?

Once or more a day (or a week, or a month, your choice), you go the topic and check for new posts.
... an alternate way is to set in your board control panel to get notifications on new posts.

Is it possible for me to summarize the posts on top as people contribute...

NO.
As long as you have not (I think) 100 posts, you are a very "junior" member and you can do very little things only.

.... and create a usable illustrated document?

Sure, this is what we old dinosaurs call "writing articles" or "writing whitepapers" , it usually involves a word processor, knowledge of English, and knowledge of the topic you write about.
Then you print it to a .pdf printer and you attach it to your post or upload to a free file hosting and post a link to it.

Seriously , let's see what happens, once we have *something* in those threads you can try summing it up in a document AND IF the result will be understandable and "nice" AND IF Nuno is in the "right mood" AND IF you undertake successfully the initiation process AND IF you make the secret oath of all bootlanders, we may think of "pushing" you up the stairs a little recommending a promotion to
Tutorial Writer...


Wonko

[LeMOGO]

Fair.
I already enabled the notification.

Let's start.