Firmware Downgrade D-Series (SamyGO Proof of Concept)

[prairie]

Successful downgrade on T-GAP8AKUC [1018->1010]. I used the option to "install later" which downloaded the FW and activated the Alternative FW option in support menu. New version was then installed with this option and I can switch back and forth. Note that version 1018 is also unrestricted. Thanks guys! One strange note, Webif shows installed version "1015".

[spewak]

Good work but i have one question :] What with warranty????

[prairie]

So now what I want to try is upgrading to restricted version. by this method, will it work?

1. Use alternate update function to go back to 1018.
2. Upgrade using "install later" to 1026
3. Test 1026 for any PQ changes (I know probably not but I have good measuring devices and I'm too curious).
4. Use alternate update function to go back to 1018.

My question is if 4. does not work, can I still use your server to load 1010 again? And if I do that will I be stuck there because I've downgraded from a restricted version. I still don't quite understand that scenario.

[spewak]

probably you have version number conflict

[arris69]

Good work but i have one question :] What with warranty????

it's unmodified samsung firmware, you asked also about warranty as you made update from samsung server?

[arris69]

So now what I want to try is upgrading to restricted version. by this method, will it work?

updates to restricted version normally end in forum ban

1. Use alternate update function to go back to 1018.
2. Upgrade using "install later" to 1026
3. Test 1026 for any PQ changes (I know probably not but I have good measuring devices and I'm too curious).
4. Use alternate update function to go back to 1018.

not sure that you have the "update to alternate version" avail, just devil knows when it's availible and when not

My question is if 4. does not work, can I still use your server to load 1010 again?

i think you have "tester status", so if you not like to update downgrade etc. every second day, think we can make a lot of things possible for you

And if I do that will I be stuck there because I've downgraded from a restricted version. I still don't quite understand that scenario.

if you downgrade from "restricted" firmware, exeDSP "should" correct the version string.

but not sure that it ends with same results if you use the "install later" option.

[prairie]

if you downgrade from "restricted" firmware, exeDSP "should" correct the version string.

You mean restricted exeDSP will write the correct version string of incoming FW in Version.0/1? This means it will get written with 1010 instead of 1090? That's good right, then I can USB update and skip the alternate trick or changing Version.0/1 string to lower version.

[arris69]

if you downgrade from "restricted" firmware, exeDSP "should" correct the version string.

You mean restricted exeDSP will write the correct version string of incoming FW in Version.0/1? This means it will get written with 1010 instead of 1090? That's good right, then I can USB update and skip the alternate trick or changing Version.0/1 string to lower version.

yes, but as i wrote its true for eurpean firmware, not sure about usa...

[juusso]

Let mission Appollo2 begin...

[prairie]

if you downgrade from "restricted" firmware, exeDSP "should" correct the version string.

You mean restricted exeDSP will write the correct version string of incoming FW in Version.0/1? This means it will get written with 1010 instead of 1090? That's good right, then I can USB update and skip the alternate trick or changing Version.0/1 string to lower version.

yes, but as i wrote its true for eurpean firmware, not sure about usa...

gotcha, ok I did some testing and here are results for T-GAP8AKUC:

-used alternate load to go back to unrestricted 1018
-usb to 1024: restricted, I had no problem to do OTA back to 1010 and it writes that version in Version.1 file
-usb to 1026: (current version listed on website), no problem going back to 1010
-Restricted versions allowed "load later" OTA option when downgrading to 1010 but the alternative FW option only works once, it get's disabled after the flash.
-I had to do all the upgrades via USB - I get "No update available" from Samsung servers after the downgrade. This happened on versions 1010 and 1024 even though 1026 is current on the website