What are the "TMB" and "USC" in the "Update info" links?
They're both US unlocked.
doc.samsungmobile.com/SM-S918U1/TMB/doc.html
doc.samsungmobile.com/SM-S918U1/USC/doc.html
They correspond to the CSC (Consumer software customization) determined by your SIM card. If you're on T-Mobile, you will see TMB. If your'e on US Cellular, you'll see USC. On an Unlocked U1 phone, there may be carrier specific changes with an update.
Guyinlaca said:
They correspond to the CSC (Consumer software customization) determined by your SIM card. If you're on T-Mobile, you will see TMB. If your'e on US Cellular, you'll see USC. On an Unlocked U1 phone, there may be carrier specific changes with an update.
Click to expand...
Click to collapse
And if someone changes their service, can the old updates that were for the old carrier pose a potential problem now that they're with the new carrier and receiving their updates?
When you remove the old SIM card and insert the new one, it will ask you to restart to apply the correct settings for your carrier. The SIM does the work for you.
Guyinlaca said:
When you remove the old SIM card and insert the new one, it will ask you to restart to apply the correct settings for your carrier. The SIM does the work for you.
Click to expand...
Click to collapse
I assumed that was just changing the APN and changing the carrier settings. But it actually undoes old updates and reinstalls them?
No. Every firmware and update has CSCs built in. It doesn't revert the software, it just activates features specific to your carrier (based on SIM). It's a partition of sorts.
Guyinlaca said:
No. Every firmware and update has CSCs built in. It doesn't revert the software, it just activates features specific to your carrier (based on SIM). It's a partition of sorts.
Click to expand...
Click to collapse
1) So when one switches from carrier one to carrier two, what happens to all the past updates that are associated with carrier one?
2) If the SIM card is removed and a new one isn't inserted (for instance if one's upgading to a new phone), will the future updates be "generic"? (Obviously when the old phone is in one's home with a wifi connection.)
1. Each U1 software update contains all US carrier CSC partitions. If you update from A7 to A8, and change SIM cards, you'd remain on A8, but the CSC partition switches to the new carrier. There is never any rolling back, merely switching from one partition to another.
2. If you remove the SIM, your phone updates using the previously set CSC. If you used a T-Mobile SIM, it stays on TMO. The default CSC on U1 is XAA and there's little reason to go back to it, though it can be done with certain tools.
Guyinlaca said:
1. Each U1 software update contains all US carrier CSC partitions. If you update from A7 to A8, and change SIM cards, you'd remain on A8, but the CSC partition switches to the new carrier. There is never any rolling back, merely switching from one partition to another.
2. If you remove the SIM, your phone updates using the previously set CSC. If you used a T-Mobile SIM, it stays on TMO. The default CSC on U1 is XAA and there's little reason to go back to it, though it can be done with certain tools.
Click to expand...
Click to collapse
Thank you.
Related
Hi, in October I bought this Samsung Galaxy S9+ second hand from a guy. I verified it to be original and be in good working order, lots of screen tests, speaker and camera tests aswell and all checked out. I didn't check for the software updates because I thought I can get them anyway since this guy told be he bought this phone from a local carrier (Telekom Romania), I'm from Romania btw. Recently I found out that Android Pie started rolling out for Note 9 and S9/S9+ so I searched for an update aswell, the only problem is that the software update menu says that my phone is up to date (Android 8.0.0) and my security patch is from August 1, 2018... Last night I looked up my IMEI on a site that I don't know if I can mention and it said that my phone is from the UK and the carrier is: OPEN United Kingdom. I haven't had any problem with my SIM card or WIFI or anything except bad signal outside big cities but I think that's normal. I also tried hooking it up to Samsung Smart Switch on my pc but found no update. If any more details needed leave a reply I will answer ASAP.
My baseband version is: G965FXXU2BRG8
Thank you.
You have an international unlocked model. The OTA updates are are distributed by region via your carrier. It's ultimately up to your carrier when they push your phone the update, however you maybe able to use Samsung's smart switch to update it. Pie was released to the UK region and the Romania region carriers may not have pushed the update yet.
Ok but what about the security patches then? The one I have is from August 2018. Don't they update OTA aswell?
Yes. They come from the same servers as firmware updates, which are distributed by your carrier. If you're not getting OTA updates, you can try removing the Sim card and doing a factory reset. After the initial setup, your sim will reinitialize and reset the CSC group your phone is tied to to ensure its actually requesting firmware for the correct region.
---------- Post added at 01:36 AM ---------- Previous post was at 01:27 AM ----------
Sounds like the phone was previously setup in the UK, factory reset, sim removed, and sold to someone in your country. In that case, because of the order the phone was decommissioned before being sold, it's requesting firmware for another region that your carrier cannot provide. If you remove the Sim and factory reset, that will change your CSC region back to "unknown" and reinserting the Sim will automatically tie the phone to your carrier and region.
hyperblu said:
Yes. They come from the same servers as firmware updates, which are distributed by your carrier. If you're not getting OTA updates, you can try removing the Sim card and doing a factory reset. After the initial setup, your sim will reinitialize and reset the CSC group your phone is tied to to ensure its actually requesting firmware for the correct region.
---------- Post added at 01:36 AM ---------- Previous post was at 01:27 AM ----------
Sounds like the phone was previously setup in the UK, factory reset, sim removed, and sold to someone in your country. In that case, because of the order the phone was decommissioned before being sold, it's requesting firmware for another region that your carrier cannot provide. If you remove the Sim and factory reset, that will change your CSC region back to "unknown" and reinserting the Sim will automatically tie the phone to your carrier and region.
Click to expand...
Click to collapse
Literally tried everything you said step by step, also contacted Samsung (they did nothing) and I'm still stuck on Android 8.0.0 and with an old security patch update. I'll try to update using the sammobile firmware even though my phone is not rooted. I searched my CSC on sammobile and there's no firmware for it
It sounds like Romanian carriers are slow about pushing frequent updates then. I was able to find your firmware on sammobile specifically for your csc, but none of them showed the latest. In this case, you won't receive timely OTA and must circumvent your carrier and do them yourself. Can you confirm if your csc has changed since removing the sim card and performing a factory reset? Or is it still tied to UK region?
I purchase a like-new condition Samsung Galaxy S9+ phone from Amazon Warehouse for international travel coming up in couple days. I figured I would have a better chance of getting an authentic phone from Amazon than from ebay sellers. I received the phone yesterday, and here is the situation with the phone:
- The box of the phone says "unlocked by Samsung"
- The sticker on the back of the phone has the model # SM-G965UZBAXAA and IMEI number of a factory unlocked phone
- The actual IMEI of the phone however shows model # SM-G965UZBAATT, which corresponds to the AT&T carrier locked phone
- When I turn on the phone, it shows T-mobile screen and has T-mobile apps on it
How do I determine whether this is a AT&T phone, or a T-mobile phone or something else? Unfortunately, I do not have either TMO or ATT sim cards that I can use to check which network the phone works on. How do I know whether this phone is unlocked and if it is will work internationally? I am not sure how to explain the imei of the phone coming up with ATT model number, yet the phone shows TMO screen.
Please help as I need to get this resolved today, and don't have time to purchase another phone. Thanks much in advance!!
prince_a1 said:
I purchase a like-new condition Samsung Galaxy S9+ phone from Amazon Warehouse for international travel coming up in couple days. I figured I would have a better chance of getting an authentic phone from Amazon than from ebay sellers. I received the phone yesterday, and here is the situation with the phone:
- The box of the phone says "unlocked by Samsung"
- The sticker on the back of the phone has the model # SM-G965UZBAXAA and IMEI number of a factory unlocked phone
- The actual IMEI of the phone however shows model # SM-G965UZBAATT, which corresponds to the AT&T carrier locked phone
- When I turn on the phone, it shows T-mobile screen and has T-mobile apps on it
How do I determine whether this is a AT&T phone, or a T-mobile phone or something else? Unfortunately, I do not have either TMO or ATT sim cards that I can use to check which network the phone works on. How do I know whether this phone is unlocked and if it is will work internationally? I am not sure how to explain the imei of the phone coming up with ATT model number, yet the phone shows TMO screen.
Please help as I need to get this resolved today, and don't have time to purchase another phone. Thanks much in advance!!
Click to expand...
Click to collapse
put any sim in it and it should work these phones are multi carrier means all the us models are the same if its att imei id say its unlocked since obviously last used was t mobile but if you put any sim in it other than att it should accept it and not say unnsuported sim and or ask for unlock code
to further this as i said the us models are all the same. They have a file called CSC which determines carrier based settings you can put in a tmobile sim and it will repersonalize for tmobile then swap to att and att will show up..
Its the way of the future and actually quite nice as one firmware pretty much covers all carriers other than specific user data which is that carriers apps
it may be unlocked obviously the listing was wrong but xaa is factory unlocked for sims, You can reflash xaa if it is unlocked for non carrier branding,But id put any sim in and see
TheMadScientist said:
They have a file called CSC which determines carrier based settings you can put in a tmobile sim and it will repersonalize for tmobile then swap to att and att will show up..
Click to expand...
Click to collapse
Thanks for your response. So if the previous owner put a T-mobile sim in the AT&T phone, then would it show the T-mobile screen at startup, and also have the T-mobile branded apps?
prince_a1 said:
Thanks for your response. So if the previous owner put a T-mobile sim in the AT&T phone, then would it show the T-mobile screen at startup, and also have the T-mobile branded apps?
Click to expand...
Click to collapse
Yes the csc files are multi carrier the phone will do a New sim inserted please reboot to apply new carrier configuration
and it will reboot and install the inserted sims carrier based bloat apps
TheMadScientist said:
Yes the csc files are multi carrier the phone will do a New sim inserted please reboot to apply new carrier configuration
and it will reboot and install the inserted sims carrier based bloat apps
Click to expand...
Click to collapse
Thanks again! Is it safe for me to do a factory reset on the phone? I wasn't sure if it was rooted and whether a factory reset might brick it. If I do a factory reset, what would it restore to - the AT&T or TMO configuration, or something else?
prince_a1 said:
Thanks again! Is it safe for me to do a factory reset on the phone? I wasn't sure if it was rooted and whether a factory reset might brick it. If I do a factory reset, what would it restore to - the AT&T or TMO configuration, or something else?
Click to expand...
Click to collapse
Yes its safe go into settings and account backup restore it should show factory data reset Thats the proper way to get rig of a google account on the device It will stay as is until a new sim is inserted factory resets have nothing to do with it
TheMadScientist said:
Yes its safe go into settings and account backup restore it should show factory data reset Thats the proper way to get rig of a google account on the device It will stay as is until a new sim is inserted factory resets have nothing to do with it
Click to expand...
Click to collapse
Thank you so much for the information! Highly appreciated!!
TheMadScientist said:
Yes the csc files are multi carrier the phone will do a New sim inserted please reboot to apply new carrier configuration
and it will reboot and install the inserted sims carrier based bloat apps
Click to expand...
Click to collapse
I downloaded the phoneinfo app, and here it what it shows:
Firmware's CSC code: XAA
Active CSC code: TMB
IMEI check shows model ending in: ATT
That made me highly confused as to whether this was a AT&T phone, a T-mobile phone or whether it was originally sold as factory unlocked.
prince_a1 said:
I downloaded the phoneinfo app, and here it what it shows:
Firmware's CSC code: XAA
Active CSC code: TMB
IMEI check shows model ending in: ATT
That made me highly confused as to whether this was a AT&T phone, a T-mobile phone or whether it was originally sold as factory unlocked.
Click to expand...
Click to collapse
So originally it was a att device. Who ever used it used it on tmobile but on xaa which is debloated unlocked
TheMadScientist said:
So originally it was a att device. Who ever used it used it on tmobile but on xaa which is debloated unlocked
Click to expand...
Click to collapse
Under Service Provider SW ver., it shows TMB/XAA/ATT
I am trying to understand what this means, why would it show TMB, XAA and ATT? Does it mean the phone was originally AT&T, then someone installed XAA firmware on it and used it on T-mobile. If that is true, is there a way for me to verify whether the current installed firmware is XAA?
prince_a1 said:
Under Service Provider SW ver., it shows TMB/XAA/ATT
I am trying to understand what this means, why would it show TMB, XAA and ATT? Does it mean the phone was originally AT&T, then someone installed XAA firmware on it and used it on T-mobile. If that is true, is there a way for me to verify whether the current installed firmware is XAA?
Click to expand...
Click to collapse
That is correct. You see it now. The third csc code is the original device. The second is what csc you have running. And the first is or was sim inserted.
Look in settings about phone and software info. At the bottom somewhere it should show you
TheMadScientist said:
That is correct. You see it now. The third csc code is the original device. The second is what csc you have running. And the first is or was sim inserted.
Look in settings about phone and software info. At the bottom somewhere it should show you
Click to expand...
Click to collapse
Yes, what I pasted above is from about phone->software info. It shows the service provider sw version as TMB/XAA/ATT. Thank you!!
Hopefully there is someone here more knowledgeable than myself that can help me. I recently ordered an S9+ SM-G9650 model from amazon with the intent of unlocking the bootloader, etc. When I got it, everything looked alright, but I got to a point in the setup when I couldn't progress without putting in a sim card. I did and it rebooted twice, one of those times showing a blue screen that from my research seems to be related to CSC and changing the software region based on the sim card inserted. My sim card is a US Tracfone AT&T version sim card by the way. After that, I finished setting up the phone and found the model number to be SM-G965U1. I have factory reset from the bootloader and from within android to no avail. From my research the CSC region change thing can only change the CSC values to certain values based on the phone's actual model number, and not the model number itself. What I am saying is, is it possible that my US sim card somehow changed my phone from the bootloader-unlockable SM-G9650 model to the locked SM-G965U1 model, or did I actually receive the wrong model device?
cosmogroid said:
Hopefully there is someone here more knowledgeable than myself that can help me. I recently ordered an S9+ SM-G9650 model from amazon with the intent of unlocking the bootloader, etc. When I got it, everything looked alright, but I got to a point in the setup when I couldn't progress without putting in a sim card. I did and it rebooted twice, one of those times showing a blue screen that from my research seems to be related to CSC and changing the software region based on the sim card inserted. My sim card is a US Tracfone AT&T version sim card by the way. After that, I finished setting up the phone and found the model number to be SM-G965U1. I have factory reset from the bootloader and from within android to no avail. From my research the CSC region change thing can only change the CSC values to certain values based on the phone's actual model number, and not the model number itself. What I am saying is, is it possible that my US sim card somehow changed my phone from the bootloader-unlockable SM-G9650 model to the locked SM-G965U1 model, or did I actually receive the wrong model device?
Click to expand...
Click to collapse
More than likely wrong model. It didn't change the bootloader. I run a9650 on cricket. I would send it back and raise hell i see this happen a lot
Hello,
I have a SIM unlocked S21 from Xfinity Mobile that I'm now using on Verizon Wireless. I need to change the CSC to VZW, anyone know how? I tried all the dialer codes, and also SamKEY but no luck so far.
SamKEY says "unsupported firmware, please downgrade your firmware".
Since January 2021, it's not easy to change CSC, some people do it by flashing firmwares then block whatever app checks SIM & CSC compatibility.
You can check this thread if you're into action.
Thanks, I tried that but somehow it ignores that the VZW SIM card is VZW, and it keeps the CSC as CCT/CCT/CCT.
Even putting in an AT&T sim card, it still keeps it as CCT/CCT/CCT. The carrier name is stuck as "Xfinity Mobile" also, no matter the SIM.
I wish Samsung would implement the "BYOD" thing already for this phone.. Or maybe SamKEY will work eventually...
What's interesting is that it changes the APN to the correct one automatically for the 3 SIM cards I've tried (VZW, CCT, ATT)
Firmware bug I guess, or Samsung has not yet fully implemented the "BYOD" feature referenced here:
Move your Galaxy phone to a different service carrier
If you unlock your phone to use with another carrier, it's easy to take advantage of all your new carrier's features without losing any of your data.
www.samsung.com
UPDATE: SamKEY worked!!
I was able to change the CSC to the correct carrier!
quadrun1 said:
UPDATE: SamKEY worked!!
I was able to change the CSC to the correct carrier!
Click to expand...
Click to collapse
how many credits do I need to change CSC?
On the samkey page it says that you need 8 credits
No, if I remember correctly it's only 1 credit to change the CSC.
See here:
https://www.reddit.com/r/GalaxyS21/comments/lm0at9
Hello,
I have an unlocked Xfinity Mobile device that I bought from Xfinity Mobile. This means that I purchased from them and then paid off the phone in full, allowing it to be unlocked. I can plug in other SIM cards (such as atnt) and have them work fine, which means that my phone is 100% unlocked. However, because Xfinity Mobile is a b*tch, APN settings are still locked for some reason, even when my phone is unlocked. I believe it has to do with the fact that carrier-specific software was installed when I first installed my Xfinity Mobile SIM card. I need to access APN settings to ensure my phone gets full functionality from my new carrier, Visible, which doesn't install any carrier-specific software because it's very new or something like that. Plus, Xfinity Mobile's carrier software doesn't allow me to manually disable 5G functionality (select what bands or whatever I want to use), which I may want to do at some point. I also think the Xfinity Mobile boot load screen is hideous, and I would like to get rid of it.
After searching around, I found out that the best way to do this was to flash U1 software to my phone using Odin with the carrier code XAA or something like that to revert my phone to the original Samsung-bought factory-unlocked state. However, after searching around some more, I found out that to do this, I would have to factory reset my phone and then re-import my apps, data, images, etc., with Smart Switch, which doesn't preserve per-app data. I have way too many apps requiring logins to dig out the passwords for each app and log in again, so I would prefer not to factory reset my phone.
Searching around some more, I found out that it was possible to retain data when switching from U to U1 by selecting the "Home CSC" file instead of the non-"Home CSC" file when flashing with Odin in the respective area where it asks for the CSC file, but this would result in a "Dirty flash" which could brick my phone. Of course, I don't want to brick my phone, so this is kind of a no-go. But, some people did say that using the "Home CSC" wouldn't affect the phone that much, and it was safe to do, but I don't want to put the safety of my shiny phone on the line.
Tl;dr: I want to go from my carrier-locked U firmware to U1 unlocked XAA without losing my data / requiring a restore with Smart Switch. Is this possible?
Both the u and u1 lost the ability to switch lte bands in the June and July updates. The last one that allows changing lte bands is the may update (cvdb etc)
How To LOCK LTE Band Without Root on SAMSUNG Device
This method is specifically for Samsung Galaxy. Because the default hiddennetwork system application is available. for devices with other brands and types, I haven't tried it. Please follow the following methods: 1. You need to install this app...
forum.xda-developers.com
robnitro said:
Both the u and u1 lost the ability to switch lte bands in the June and July updates. The last one that allows changing lte bands is the may update (cvdb etc)
How To LOCK LTE Band Without Root on SAMSUNG Device
This method is specifically for Samsung Galaxy. Because the default hiddennetwork system application is available. for devices with other brands and types, I haven't tried it. Please follow the following methods: 1. You need to install this app...
forum.xda-developers.com
Click to expand...
Click to collapse
Well, I still want to flash U1. Would flashing U1 Home_CSC bootloop my phone
garailcat said:
Well, I still want to flash U1. Would flashing U1 Home_CSC bootloop my phone
Click to expand...
Click to collapse
So then the phone is NOT giving you the popup prompt to reboot to apply new carrier settings, when you insert a different SIM? And it still shows all of the Xfinity bloat and their configuration?
iBowToAndroid said:
So then the phone is NOT giving you the popup prompt to reboot to apply new carrier settings, when you insert a different SIM? And it still shows all of the Xfinity bloat and their configuration?
Click to expand...
Click to collapse
No, if I put in an ATNT SIM, it will switch to ATNT software and install its respective bloat.
However, my current service provider, Visible, does not have its carrier software/firmware. Therefore it would make no sense for me to use Visible on Xfinity Mobile carrier software.
garailcat said:
No, if I put in an ATNT SIM, it will switch to ATNT software and install its respective bloat.
Click to expand...
Click to collapse
So then can you leave it on AT&T bloat, since that firmware allows APN change/add...?
iBowToAndroid said:
So then can you leave it on AT&T bloat, since that firmware allows APN change/add...?
Click to expand...
Click to collapse
No.
I'd rather blow my brains out than have 300 useless apps. Also, the actual data indicator icon thing looks ugly as all hell.
Xfinity mobile is more stock than the other bigger providers regarding bloat and other things; it's just that it doesn't allow APN editing, which is incredibly annoying.