Author Topic: 84+/SE Boot Pages Modified  (Read 36896 times)

0 Members and 1 Guest are viewing this topic.

Offline Deep Toaster

  • So much to do, so much time, so little motivation
  • Administrator
  • LV13 Extreme Addict (Next: 9001)
  • *************
  • Posts: 8217
  • Rating: +758/-15
    • View Profile
    • ClrHome
Re: 84+/SE Boot Pages Modified
« Reply #30 on: June 27, 2011, 02:44:32 pm »
It's lower than that. You could think of the TI-OS itself as one big program that's being run by the boot code.




Offline ruler501

  • Meep
  • LV11 Super Veteran (Next: 3000)
  • ***********
  • Posts: 2475
  • Rating: +66/-9
  • Crazy Programmer
    • View Profile
Re: 84+/SE Boot Pages Modified
« Reply #31 on: June 27, 2011, 02:45:54 pm »
IT appears it is a program that actually runs the calculator. The OS has to go through it I think. It runs pretty much everything I think
I currently don't do much, but I am a developer for a game you should totally try out called AssaultCube Reloaded download here https://assaultcuber.codeplex.com/
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GCM/CS/M/S d- s++: a---- C++ UL++ P+ L++ E---- W++ N o? K- w-- o? !M V?
PS+ PE+ Y+ PGP++ t 5? X R tv-- b+++ DI+ D+ G++ e- h! !r y

Offline Darl181

  • «Yo buddy, you still alive?»
  • CoT Emeritus
  • LV12 Extreme Poster (Next: 5000)
  • *
  • Posts: 3408
  • Rating: +305/-13
  • VGhlIEdhbWU=
    • View Profile
    • darl181.webuda.com
Re: 84+/SE Boot Pages Modified
« Reply #32 on: June 27, 2011, 02:46:08 pm »
So the boot code also checks that it's actually TIOS it's running instead of a third-party OS.  (hence signing keys?)  Also it limits TIOS.
Now that it's editable.. ;D
Vy'o'us pleorsdti thl'e gjaemue

Offline ruler501

  • Meep
  • LV11 Super Veteran (Next: 3000)
  • ***********
  • Posts: 2475
  • Rating: +66/-9
  • Crazy Programmer
    • View Profile
Re: 84+/SE Boot Pages Modified
« Reply #33 on: June 27, 2011, 02:46:51 pm »
So the boot code also checks that it's actually TIOS it's running instead of a third-party OS.  (hence signing keys?)  Also it limits TIOS.
Now that it's editable.. ;D
Yep no control by TI over the calculator >:)
I currently don't do much, but I am a developer for a game you should totally try out called AssaultCube Reloaded download here https://assaultcuber.codeplex.com/
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GCM/CS/M/S d- s++: a---- C++ UL++ P+ L++ E---- W++ N o? K- w-- o? !M V?
PS+ PE+ Y+ PGP++ t 5? X R tv-- b+++ DI+ D+ G++ e- h! !r y

Offline Deep Toaster

  • So much to do, so much time, so little motivation
  • Administrator
  • LV13 Extreme Addict (Next: 9001)
  • *************
  • Posts: 8217
  • Rating: +758/-15
    • View Profile
    • ClrHome
Re: 84+/SE Boot Pages Modified
« Reply #34 on: June 27, 2011, 02:48:32 pm »
So the boot code also checks that it's actually TIOS it's running instead of a third-party OS.  (hence signing keys?)  Also it limits TIOS.
Now that it's editable.. ;D

It doesn't check if the TI-OS is running -- it runs the TI-OS. Think of the TI-OS as one big program that gets run from the boot code. Even when your calculator "turns off," the TI-OS is still running (that's why it still uses power, and that's why you can't remove all five batteries without resetting RAM). When your calc crashes, it goes back to the boot code to check if there's an OS and start it up.




Offline ruler501

  • Meep
  • LV11 Super Veteran (Next: 3000)
  • ***********
  • Posts: 2475
  • Rating: +66/-9
  • Crazy Programmer
    • View Profile
Re: 84+/SE Boot Pages Modified
« Reply #35 on: June 27, 2011, 02:51:38 pm »
So the boot code also checks that it's actually TIOS it's running instead of a third-party OS.  (hence signing keys?)  Also it limits TIOS.
Now that it's editable.. ;D

It doesn't check if the TI-OS is running -- it runs the TI-OS. Think of the TI-OS as one big program that gets run from the boot code. Even when your calculator "turns off," the TI-OS is still running (that's why it still uses power, and that's why you can't remove all five batteries without resetting RAM). When your calc crashes, it goes back to the boot code to check if there's an OS and start it up.
So turning the calc off is more like putting it into standby mode right?
I currently don't do much, but I am a developer for a game you should totally try out called AssaultCube Reloaded download here https://assaultcuber.codeplex.com/
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GCM/CS/M/S d- s++: a---- C++ UL++ P+ L++ E---- W++ N o? K- w-- o? !M V?
PS+ PE+ Y+ PGP++ t 5? X R tv-- b+++ DI+ D+ G++ e- h! !r y

Offline Deep Toaster

  • So much to do, so much time, so little motivation
  • Administrator
  • LV13 Extreme Addict (Next: 9001)
  • *************
  • Posts: 8217
  • Rating: +758/-15
    • View Profile
    • ClrHome
Re: 84+/SE Boot Pages Modified
« Reply #36 on: June 27, 2011, 02:53:48 pm »
Pretty much.




Offline Lionel Debroux

  • LV11 Super Veteran (Next: 3000)
  • ***********
  • Posts: 2135
  • Rating: +290/-45
    • View Profile
    • TI-Chess Team
Re: 84+/SE Boot Pages Modified
« Reply #37 on: June 27, 2011, 03:06:47 pm »
It's very good news, and renewed proof to TI's extensive and long-lasting fail at controlling their devices... Two different flaws found independently in parallel, congratulations :D
Once again, the search for flaws was a consequence of a negative move by TI, towards further locking of their calculators. Let's keep going on, together, with that pattern :)
« Last Edit: June 27, 2011, 03:09:35 pm by Lionel Debroux »
Member of the TI-Chess Team.
Co-maintainer of GCC4TI (GCC4TI online documentation), TILP and TIEmu.
Co-admin of TI-Planet.

Offline alberthrocks

  • Moderator
  • LV8 Addict (Next: 1000)
  • ********
  • Posts: 876
  • Rating: +103/-10
    • View Profile
Re: 84+/SE Boot Pages Modified
« Reply #38 on: June 27, 2011, 03:10:33 pm »
There is a free boot code out there called BootFree, developed by Benjamin Moody (FloppusMaximus). It's quite hard to find... but you might be able to extract it from the Wabbitemu source code. ;)

EDIT: Found a topic that mentions and gives a link... which is broken. :P http://www.revsoft.org/phpBB3/viewtopic.php?f=32&t=608&start=45
« Last Edit: June 27, 2011, 03:11:17 pm by alberthrocks »
Withgusto Networks Founder and Administrator
Main Server Status: http://withg.org/status/
Backup Server Status: Not available
Backup 2/MC Server Status: http://mc.withg.org/status/


Proud member of ClrHome!

Miss my old signature? Here it is!
Spoiler For Signature:
Alternate "New" IRC post notification bot (Newy) down? Go here to reset it! http://withg.org/albert/cpuhero/

Withgusto Networks Founder and Administrator
Main Server Status: http://withg.org/status/
Backup Server Status: Not available
Backup 2/MC Server Status: http://mc.withg.org/status/

Activity remains limited due to busyness from school et al. Sorry! :( Feel free to PM, email, or if you know me well enough, FB me if you have a question/concern. :)

Don't expect me to be online 24/7 until summer. Contact me via FB if you feel it's urgent.


Proud member of ClrHome!

Spoiler For "My Projects! :D":
Projects:

Computer/Web/IRC Projects:
C______c: 0% done (Doing planning and trying to not forget it :P)
A_____m: 40% done (Need to develop a sophisticated process queue, and a pretty web GUI)
AtomBot v3.0: 0% done (Planning stage, may do a litmus test of developer wants in the future)
IdeaFrenzy: 0% done (Planning and trying to not forget it :P)
wxWabbitemu: 40% done (NEED MOAR FEATURES :P)

Calculator Projects:
M__ C_____ (an A____ _____ clone): 0% done (Need to figure out physics and Axe)
C2I: 0% done (planning, checking the demand for it, and dreaming :P)

Offline calc84maniac

  • eZ80 Guru
  • Coder Of Tomorrow
  • LV11 Super Veteran (Next: 3000)
  • ***********
  • Posts: 2912
  • Rating: +471/-17
    • View Profile
    • TI-Boy CE
Re: 84+/SE Boot Pages Modified
« Reply #39 on: June 27, 2011, 03:12:09 pm »
There is a free boot code out there called BootFree, developed by Benjamin Moody (FloppusMaximus). It's quite hard to find... but you might be able to extract it from the Wabbitemu source code. ;)

EDIT: Found a topic that mentions and gives a link... which is broken. :P http://www.revsoft.org/phpBB3/viewtopic.php?f=32&t=608&start=45
Since it was designed exclusively for emulators, I don't think it has any code to receive an OS over link cable.
"Most people ask, 'What does a thing do?' Hackers ask, 'What can I make it do?'" - Pablos Holman

Offline thepenguin77

  • z80 Assembly Master
  • LV10 31337 u53r (Next: 2000)
  • **********
  • Posts: 1594
  • Rating: +823/-5
  • The game in my avatar is bit.ly/p0zPWu
    • View Profile
Re: 84+/SE Boot Pages Modified
« Reply #40 on: June 27, 2011, 03:14:06 pm »
The boot code has two purposes. 1) To receive OS's, 2) To prepare the calculator hardware to run the operating system.

Receiving OS's is one of the boot codes two purposes. Whenever you see the OS percentage screen, that is the boot code. The boot code also makes it appearance in "Waiting... Please send operating system now." However, even if the boot code couldn't receive OS's for whatever reason, this really isn't too bad as there are ways to glitch it.


But the primary purpose of the boot code is to prepare the calculator hardware for an OS and then jump to the OS to let it start executing. Whenever power is cut from the calculator, all of the hardware stuff dies. Then, when power returns, execution starts at the boot code. The boot code sets up all of the calculator hardware, checks to make sure that an OS is installed, and then jump to the OS. But the key thing here is that the boot code is run first no matter what. If you pull a battery, the next thing that is going to run is the boot code. (Unless the calculator is turned off, then you have like 5 secs to put it back in.) So if the boot code is missing, the calculator will crash as soon as a battery is inserted. And when it crashes, guess where it goes. The boot code. This would be an endless loop, and the end of your calculator.
zStart v1.3.013 9-20-2013 
All of my utilities
TI-Connect Help
You can build a statue out of either 1'x1' blocks or 12'x12' blocks. The 1'x1' blocks will take a lot longer, but the final product is worth it.
       -Runer112

Offline alberthrocks

  • Moderator
  • LV8 Addict (Next: 1000)
  • ********
  • Posts: 876
  • Rating: +103/-10
    • View Profile
Re: 84+/SE Boot Pages Modified
« Reply #41 on: June 27, 2011, 03:18:34 pm »
There is a free boot code out there called BootFree, developed by Benjamin Moody (FloppusMaximus). It's quite hard to find... but you might be able to extract it from the Wabbitemu source code. ;)

EDIT: Found a topic that mentions and gives a link... which is broken. :P http://www.revsoft.org/phpBB3/viewtopic.php?f=32&t=608&start=45
Since it was designed exclusively for emulators, I don't think it has any code to receive an OS over link cable.
Well, you still have half the functionality! ;) Now it just needs to be improved to get receiving and sending support, this time with a pretty progress bar? :P

This would be an endless loop, and the end of your calculator.
... unless you take the time to attempt to reprogram your flash chip. :P I've heard some convo about it a while ago, not sure if any breakthrough was found.
Withgusto Networks Founder and Administrator
Main Server Status: http://withg.org/status/
Backup Server Status: Not available
Backup 2/MC Server Status: http://mc.withg.org/status/


Proud member of ClrHome!

Miss my old signature? Here it is!
Spoiler For Signature:
Alternate "New" IRC post notification bot (Newy) down? Go here to reset it! http://withg.org/albert/cpuhero/

Withgusto Networks Founder and Administrator
Main Server Status: http://withg.org/status/
Backup Server Status: Not available
Backup 2/MC Server Status: http://mc.withg.org/status/

Activity remains limited due to busyness from school et al. Sorry! :( Feel free to PM, email, or if you know me well enough, FB me if you have a question/concern. :)

Don't expect me to be online 24/7 until summer. Contact me via FB if you feel it's urgent.


Proud member of ClrHome!

Spoiler For "My Projects! :D":
Projects:

Computer/Web/IRC Projects:
C______c: 0% done (Doing planning and trying to not forget it :P)
A_____m: 40% done (Need to develop a sophisticated process queue, and a pretty web GUI)
AtomBot v3.0: 0% done (Planning stage, may do a litmus test of developer wants in the future)
IdeaFrenzy: 0% done (Planning and trying to not forget it :P)
wxWabbitemu: 40% done (NEED MOAR FEATURES :P)

Calculator Projects:
M__ C_____ (an A____ _____ clone): 0% done (Need to figure out physics and Axe)
C2I: 0% done (planning, checking the demand for it, and dreaming :P)

Offline DJ Omnimaga

  • Clacualters are teh gr33t
  • CoT Emeritus
  • LV15 Omnimagician (Next: --)
  • *
  • Posts: 55942
  • Rating: +3154/-232
  • CodeWalrus founder & retired Omnimaga founder
    • View Profile
    • Dream of Omnimaga Music
Re: 84+/SE Boot Pages Modified
« Reply #42 on: June 27, 2011, 03:27:44 pm »
This is great news. I read about the boot code exploit for a few days now and I must say those exploits will really need to be bug-free when coming out, since it could be dangerous otherwise (calc bricking), but when they're perfect this will give us even more control on our calcs.
So the boot code also checks that it's actually TIOS it's running instead of a third-party OS.  (hence signing keys?)  Also it limits TIOS.
Now that it's editable.. ;D

It doesn't check if the TI-OS is running -- it runs the TI-OS. Think of the TI-OS as one big program that gets run from the boot code. Even when your calculator "turns off," the TI-OS is still running (that's why it still uses power, and that's why you can't remove all five batteries without resetting RAM). When your calc crashes, it goes back to the boot code to check if there's an OS and start it up.
So turning the calc off is more like putting it into standby mode right?
Indeed. In fact in ASM in 28 days, they say to really turn the calc OFF, you must remove all five batteries (including the lithium one)
« Last Edit: June 27, 2011, 03:28:45 pm by DJ_O »

Offline alberthrocks

  • Moderator
  • LV8 Addict (Next: 1000)
  • ********
  • Posts: 876
  • Rating: +103/-10
    • View Profile
Re: 84+/SE Boot Pages Modified
« Reply #43 on: June 27, 2011, 03:41:10 pm »
That's correct. :) If you ran, say, KOS or RougeOS, and you took the batteries out, the screen would fade away gradually.
However... if you took the batteries out when running TI-OS, it detect the occurrence and shuts the calc off into a "RAM safe mode", waiting for you to put batteries back in.

Above info not known nor discovered by me, but by the magnificent BrandonW! Great job! :D
Withgusto Networks Founder and Administrator
Main Server Status: http://withg.org/status/
Backup Server Status: Not available
Backup 2/MC Server Status: http://mc.withg.org/status/


Proud member of ClrHome!

Miss my old signature? Here it is!
Spoiler For Signature:
Alternate "New" IRC post notification bot (Newy) down? Go here to reset it! http://withg.org/albert/cpuhero/

Withgusto Networks Founder and Administrator
Main Server Status: http://withg.org/status/
Backup Server Status: Not available
Backup 2/MC Server Status: http://mc.withg.org/status/

Activity remains limited due to busyness from school et al. Sorry! :( Feel free to PM, email, or if you know me well enough, FB me if you have a question/concern. :)

Don't expect me to be online 24/7 until summer. Contact me via FB if you feel it's urgent.


Proud member of ClrHome!

Spoiler For "My Projects! :D":
Projects:

Computer/Web/IRC Projects:
C______c: 0% done (Doing planning and trying to not forget it :P)
A_____m: 40% done (Need to develop a sophisticated process queue, and a pretty web GUI)
AtomBot v3.0: 0% done (Planning stage, may do a litmus test of developer wants in the future)
IdeaFrenzy: 0% done (Planning and trying to not forget it :P)
wxWabbitemu: 40% done (NEED MOAR FEATURES :P)

Calculator Projects:
M__ C_____ (an A____ _____ clone): 0% done (Need to figure out physics and Axe)
C2I: 0% done (planning, checking the demand for it, and dreaming :P)

Offline thepenguin77

  • z80 Assembly Master
  • LV10 31337 u53r (Next: 2000)
  • **********
  • Posts: 1594
  • Rating: +823/-5
  • The game in my avatar is bit.ly/p0zPWu
    • View Profile
Re: 84+/SE Boot Pages Modified
« Reply #44 on: June 27, 2011, 04:24:23 pm »
Indeed. In fact in ASM in 28 days, they say to really turn the calc OFF, you must remove all five batteries (including the lithium one)

We actually now know better than that. The calculator is off a few hundreths of a second after you pull out a AAA. The reason it appears that it didn't shut off is because the lithium battery kept the ram intact. Execution still starts at the boot code. But, I guess if you call ram intact powered, then yes, it takes all 5 batteries.

That's correct. :) If you ran, say, KOS or RougeOS, and you took the batteries out, the screen would fade away gradually.
However... if you took the batteries out when running TI-OS, it detect the occurrence and shuts the calc off into a "RAM safe mode", waiting for you to put batteries back in.

If you pull the batteries while the calculator is ON, the screen will blank, it won't fade. You can see this happen if you pull the batteries during an assembly program.
« Last Edit: June 27, 2011, 04:36:46 pm by thepenguin77 »
zStart v1.3.013 9-20-2013 
All of my utilities
TI-Connect Help
You can build a statue out of either 1'x1' blocks or 12'x12' blocks. The 1'x1' blocks will take a lot longer, but the final product is worth it.
       -Runer112