After FMCB has been loaded to be exact, but I saw now that you stated the correct 'order' later on in your post.
Originally Posted by SP193
PS2-PowerOn/Reset --> rom0:OSDSYS --> Searches for MC-Update in region-specific folder...
...if found --> executes the KELF
...if not found --> continiues with the Sony-Logo/Intro-Sequence, powers HD on, if present and searches for HD-Update...
So,... FMCB is found and executed,... If the OSDSYS-Mod-Subprogramm is invoked/started, it loads&(unpacks, where necessary&)patches the OSDSYS in RAM, like you said. How the OSDMod-Subprogramm handles the patching (so what is patched where), can be controlled by the CNF.
So,... OSDSYS is now patched and in RAM, it only must be executed now, so now it is simply executed (and voila, you have a configurable-patched OSDSYS and all that done, with a Mini-DVDELF...).
Also, just to mention it. Not all OSDSYS-Options, which you can do in CNF are actually directly related to the OSDMod-Subprogramm itself.
Some functions are args, with which the OSDSYS is executed.
For example 'SkipMC', 'SkipHD' (depending on the PS2-model, those which do not support this arg natively, get the support 'patched in' first ), 'Alt+Num7'-Visual stuff (the OSD-Mod only patches the text-string 'blindly', but the OSDSYSs native Text-Parser handles the Alt+Num7 and other visual stuff...).
When you switch off or reset the console, the contents in RAM is lost.
FMCB does not modify any part of your console's ROM.
The menu of the PS2 (OSDSYS) is stored in the console's ROM as rom0:OSDSYS.
When FMCB is booted, FMCB loads OSDSYS into RAM and modifies it.
This process is done realtime as no modified copy of rom0:OSDSYS is stored anywhere.
That's not really a problem, but he needs to be aware that he wil have 22 not accessable FAT/FS-Sectors (which are of 512Byte-Size on PS2-MC normally thought...), when he deletes a Multi-Install this way.
You mean removing FMCB from your MC?
Just delete the B*EXEC and B*DATA folders, and FMCB will be gone.
Not much thought, but it isn't such a clean uninstall like it would be if he 'transform' the 'Multi-Install' back to a 'Normal-Install' and then deletes the folder...
PS2 V7/DMS3 V2 (FW:2.4b7); Seagate Baracuda 200GB
PS2 V7/CC1.0 (FW:34 hacked v2 BM:2.1.6); Maxtor DiamondMAX9 PLUS 160GB
PS2 SCPH-30004R; NoMod+NoLaser
3xSony MC 8MB
MAX/Datel 16MB with Boot-CD
Custom FMCB 1.8b+ Beta-Build, my AIO 0.5, Sony&xRhino-Linux