Related
I would like to know if it's possible to flash the firmware for
T-mobile I'm looking to leave verizon I know that the Verizon variant does not have 2 of the lte bands that T-mobile uses can I use Odin to Flash the 935t firmware to get the band's or am I asking something that is not possible. Thanks in advance
Rich7591110 said:
I would like to know if it's possible to flash the firmware for
T-mobile I'm looking to leave verizon I know that the Verizon variant does not have 2 of the lte bands that T-mobile uses can I use Odin to Flash the 935t firmware to get the band's or am I asking something that is not possible. Thanks in advance
Click to expand...
Click to collapse
The answer is NO you're asking firmware to replace/add hardware and that's not possible
I have a Verizon branded s7 edge and used Odin to load the 935U PI3 firmware. I am on T-Mo now and do have LTE band 12 working (validated with LTE Discovery). The research that I did found that the US variants have all the radios in them, but some carrier variants of firmware disable certain bands. By doing the 935U firmware, I also got rid of the notice on every reboot that I was using a non-Verizon SIM. So I now have all T-mo bands and no stupid SIM message.
Rich7591110 said:
I would like to know if it's possible to flash the firmware for
T-mobile I'm looking to leave verizon I know that the Verizon variant does not have 2 of the lte bands that T-mobile uses can I use Odin to Flash the 935t firmware to get the band's or am I asking something that is not possible. Thanks in advance
Click to expand...
Click to collapse
I can vouch for same experience as SF-IT guy. I bought a G935V and flashed with G935U firmware via odin. Works on T-mobile, even wifi calling works. Currently on the latest PI3 version of G935U firmware. I would that you search the forum to see if you can flash the G935T firmware directly. The only downside of using G935U firmware is that the FM radio chip is not enabled in the firmware. I read that the all the carrier versions (September security patch and newer) of the G935 firmware have the FM radio chip enabled. I prefer the 935U version because it there is not carrier bloatware. Samsung bloatware is still there.
davekung said:
I can vouch for same experience as SF-IT guy. I bought a G935V and flashed with G935U firmware via odin. Works on T-mobile, even wifi calling works. Currently on the latest PI3 version of G935U firmware. I would that you search the forum to see if you can flash the G935T firmware directly. The only downside of using G935U firmware is that the FM radio chip is not enabled in the firmware. I read that the all the carrier versions (September security patch and newer) of the G935 firmware have the FM radio chip enabled. I prefer the 935U version because it there is not carrier bloatware. Samsung bloatware is still there.
Click to expand...
Click to collapse
So what would the FM radio chip do? Just enable FM radios is all? Because if that's the downside then it's not a major setback as not too many people use the FM radio.
I don't think you can
cyoo97 said:
I don't think you can
Click to expand...
Click to collapse
You definitely can. All US versions of the S7 & S7 Edge are the same hardware and can be flashed to any other US firmware. (including the U firmware that automatically works on all 4 carriers)
andrewNY said:
You definitely can. All US versions of the S7 & S7 Edge are the same hardware and can be flashed to any other US firmware. (including the U firmware that automatically works on all 4 carriers)
Click to expand...
Click to collapse
So what you're saying is that flashing the U version firmware will unlock by default all 930"X" and 935"X" phones? As in it just unlocks the mofo and debloats some while you're at it?
What's the catch? It seems too easy
Tin_Man_0 said:
So what you're saying is that flashing the U version firmware will unlock by default all 930"X" and 935"X" phones? As in it just unlocks the mofo and debloats some while you're at it?
What's the catch?
Click to expand...
Click to collapse
Bloat is definitely gone on the U firmware, which is great. My phone runs faster and has more free space too.
I think some carrier features aren't supported on the U firmware. On T-mobile everything works (VoLTE and Wi-Fi Calling), but I think AT&T might have some issues with those.
If the phone is SIM locked to a particular carrier, I'm not sure that automatically gets turned off or not when you switch to the U firmware. You might need to contact your carrier first to get an unlock code?
andrewNY said:
Bloat is definitely gone on the U firmware, which is great. My phone runs faster and has more free space too.
I think some carrier features aren't supported on the U firmware. On T-mobile everything works (VoLTE and Wi-Fi Calling), but I think AT&T might have some issues with those.
If the phone is SIM locked to a particular carrier, I'm not sure that automatically gets turned off or not when you switch to the U firmware. You might need to contact your carrier first to get an unlock code?
Click to expand...
Click to collapse
What if I got a temporary unlock from t-mobile unlock app and then flashed this firmware? Would it make it permanent? Seems quite possible, but I don't know if the temporary unlock actually unlocks the phone or just inserts a bypass that would disappear if flashed.
andrewNY said:
Bloat is definitely gone on the U firmware, which is great. My phone runs faster and has more free space too.
I think some carrier features aren't supported on the U firmware. On T-mobile everything works (VoLTE and Wi-Fi Calling), but I think AT&T might have some issues with those.
If the phone is SIM locked to a particular carrier, I'm not sure that automatically gets turned off or not when you switch to the U firmware. You might need to contact your carrier first to get an unlock code?
Click to expand...
Click to collapse
I unlocked my US TMo phone when stock, rooted, and am running Echoe - which has a glitch where WiFi calling sort of works (can receive calls but not make them). In the TMo forum, there are threads on U - your comments here are more specific to what I am interested.
Which U firmware are you on and are you rooted (is is updated to latest v4 bootloader version), and did you have to ODIN and full wipe with CSC or did you get by with CSC Home to preserve data?
Also, are you on U CP or did you flash TMo CP to get all the bands?.
.
duplicate - XDA burped
Thanks everyone
I've been searching and can't find a definitive way of flashing TMobile firmware to the unlocked s8.
davwman said:
I've been searching and can't find a definitive way of flashing TMobile firmware to the unlocked s8.
Click to expand...
Click to collapse
I assume you have US Unlocked S8....
Normally you don't need to flash it with T-Mobile firmware because most of features are supported such as: VoLTE, Band 12 and WiFi Calling. If you do decide to flash here is the tread: https://forum.xda-developers.com/galaxy-s8/how-to/snap-guide-flashing-standard-fw-carrier-t3625817
Yes US unlocked. The TMobile radios are better and utilize the new tech that TMobile uses. I'm assuming I can use just the radios, but there aren't any definite answers.
I am trying to get figure out the same answer.
I also have the G950U1 and would like to flash the T-Mobile firmware to obtain the 256qam and 4x4 radio.
I'm still searching for an answer.
There is also T-Mobile firmware that doesn't have bloatware, but I don't know if it is missing any feature that you guys are looking for. I do have an unlocked S8, but haven't flashed it yet.
I've attempted using both Odin, and the modified PriceComsy Odin to flash the T-Mobile G950u firmware onto the Unlocked G950U1, and it results in FAIL! (DeviceInfo).
Ended up just flashing the modem. Just need to see how this thing works now
In case anyone wanted to know how the T-Mobile modems work on the unlocked variant, I'd say quite well with all TMobile features working
davwman said:
In case anyone wanted to know how the T-Mobile modems work on the unlocked variant, I'd say quite well with all TMobile features working
Click to expand...
Click to collapse
But what kind of speeds did you have before that?
I am going to go off the limb and suggest that flashing the 950u T-Mobile Firmware doesn't give us the 4x4 MiMo Radio and 256QAM. I've not seen a difference in call quality, data speed, or signal strength. Can anyone let the community know what the three TMB/TMB/XAA mean?
This should be a big decision differentiator when selecting between the S8 unlocked and S8 T-Mobile branded device on the T-Mobile network.
zone23 said:
But what kind of speeds did you have before that?
Click to expand...
Click to collapse
The fastest speed that is in the screen shot, half of that. Also I've noticed I don't get random lte to H drops anymore where I normally would in weak TMobile areas.
While enjoying the bloat-free experience on the 950U1 firmware, do I still have 4x4 MIMO and other good stuff exclusive on the t-mobile software that the phone came with? Thanks!
Not trying to revive a dead thread, but I am curious if anyone can chime in on this subject? I have the SM-G955U1, but was wondering if 4x4 MIMO, 256QAM is all running, or is it best to flash T-Mobile firmware?
Just find the thread on.flashing csc or userdata
I used T-Mobile on my U1 S8 for awhile and everything seemed to work (Wi-Fi Calling, frequency bands, etc.). However, from what I’ve heard T-Mobile seems to be the only carrier that works this well with the unlocked S8 firmware. You might be better off to try the T-Mobile firmware though, as you wouldn’t have to wonder whether or not any capabilities were supported, and carrier devices have been getting OS updates quicker than the unlocked firmware devices.
I need help please I have the 950u1 on crf6 I want to flash tmobile firmware but it says fails please someone help me
I got the official Oreo on the u firmware, does anyone else have it and what are your thoughts i.e. Battery and screen on time, it seems a little faster to me.
cmlucht said:
I got the official Oreo on the u firmware, does anyone else have it and what are your thoughts i.e. Battery and screen on time, it seems a little faster to me.
Click to expand...
Click to collapse
I just flashed the stock Oreo G935UUEU4CRG2 firmware (Vzw) today. I will run it bone stock for a week and report back. I should be able to tell if there's a significant difference in battery life and performance from the stock V firmware because I've never rooted my S7 edge and have run the stock Verizon firmware since new. With this Oreo U firmware, I do hate how Samsung Pay has that quick launch edge feature at the bottom of the homescreen that can't be removed.
I am very interested in the U version of the firmware . I have the Verizon Galaxy S7 Edge G935V w/ Android 8.0 but use it on Straight Talk with their AT&T sim card.
I had to change it from CDMA to GSM, also had to add a new APN for Straight talk.
It works but the phone is missing LTE bands 12 and 17. Band 17 is used in my area and without it the phone connects
to a different band and its weak in my area.
I am trying to learn if I can put the G935U (AT&T) firmware on the G935V and will I get band 17.
I know band 17 is in my area because of my previous phone of a week ago, Nexus 5.
Would you know if it can be done, and where would I find recent info how to do this
along with what bands and features would be offered or not available.
Thanks,
Ken
tx_dbs_tx said:
I just flashed the stock Oreo G935UUEU4CRG2 firmware (Vzw) today. I will run it bone stock for a week and report back. I should be able to tell if there's a significant difference in battery life and performance from the stock V firmware because I've never rooted my S7 edge and have run the stock Verizon firmware since new. With this Oreo U firmware, I do hate how Samsung Pay has that quick launch edge feature at the bottom of the homescreen that can't be removed.
Click to expand...
Click to collapse
On my G935V, flashed with U Nougat firmware I have received the Oreo U upgrade.
It works great, the only issue is that it reverted the LTE bands to the typical V version bands. I had to re-activate the other LTE bands, just because... I can. My provider is still a Verizon MVNO, and VoLTE is working.
What I like about the Oreo is the Bluetooth codecs - besides the aptX and Samsung HD (UHQ) now Google provided native support for LDAC (Sony). I couldn't wait to get that, because I really wanted my Sony's MDR-1ABT headphones to be used in their full glory (LDAC codec).
PS: To appreciate the quality difference you need to listen to FLAC files.
KenKK said:
I am very interested in the U version of the firmware . I have the Verizon Galaxy S7 Edge G935V w/ Android 8.0 but use it on Straight Talk with their AT&T sim card.
I had to change it from CDMA to GSM, also had to add a new APN for Straight talk.
It works but the phone is missing LTE bands 12 and 17. Band 17 is used in my area and without it the phone connects
to a different band and its weak in my area.
I am trying to learn if I can put the G935U (AT&T) firmware on the G935V and will I get band 17.
I know band 17 is in my area because of my previous phone of a week ago, Nexus 5.
Would you know if it can be done, and where would I find recent info how to do this
along with what bands and features would be offered or not available.
Thanks,
Ken
Click to expand...
Click to collapse
Ken, first check out the supported bands between the Verizon and the AT&T S7 edge in the link below. It will confirm the discrepancy in supported bands between the two models.
https://www.phonemore.com/compare/p...5v-vs-samsung-galaxy-s7-edge-sm-g935a/3296028
Then go to this link and download, extract and Odin flash the AT&T "U" firmware and see if that will open up the AT&T bands for your Verizon S7 edge. It very well might. I think you should also choose the option in Odin to "Clear EFS" before you flash so that it can be rewritten fresh upon bootup with your AT&T sim card. Do this and report back your results. Good luck.
https://updato.com/firmware-archive-select-model?record=0A1AF06A906411E89F15FA163EE8F90B
Thank you for your reply.
I am downloading the firmware G935U (AT&T) firmware now. Its going to take several hours because I am not a member of that download site.
I did he A/B comparison and both phones seem to be identical except for the band coverage. The AT&T has band 12 which from my reading
is 700MHz and it includes the segment band 17 has so if I understand it right if I have band 12 I should be in good shape.
It also seems to have all the bands of the 935V except for band 13. The 935A has actually more bands of coverage.
Could you clear something up for me. Once I do this I am reading I can't go back to the Version S7 Edge G935V.
However would I be able to convert it to one of the other carriers like T-mobile ?
You are the first that stated to check the EFS box.
With ODIN I will be choosing all 4 files but making sure I do NOT choose the HOME file, is that correct?
After flashing are there any other special instructions I need to do or will the phone right after flashing just
need to go through the normal setup along with possible adding the same APN config I am using with it on Straight talk w/ the straight talk AT&T sim?
thank you,
Ken
tx_dbs_tx said:
Ken, first check out the supported bands between the Verizon and the AT&T S7 edge in the link below. It will confirm the discrepancy in supported bands between the two models.
https://www.phonemore.com/compare/p...5v-vs-samsung-galaxy-s7-edge-sm-g935a/3296028
Then go to this link and download, extract and Odin flash the AT&T "U" firmware and see if that will open up the AT&T bands for your Verizon S7 edge. It very well might. I think you should also choose the option in Odin to "Clear EFS" before you flash so that it can be rewritten fresh upon bootup with your AT&T sim card. Do this and report back your results. Good luck.
https://updato.com/firmware-archive-select-model?record=0A1AF06A906411E89F15FA163EE8F90B
Click to expand...
Click to collapse
KenKK said:
Thank you for your reply.
I am downloading the firmware G935U (AT&T) firmware now. Its going to take several hours because I am not a member of that download site.
I did he A/B comparison and both phones seem to be identical except for the band coverage. The AT&T has band 12 which from my reading
is 700MHz and it includes the segment band 17 has so if I understand it right if I have band 12 I should be in good shape.
It also seems to have all the bands of the 935V except for band 13. The 935A has actually more bands of coverage.
Could you clear something up for me. Once I do this I am reading I can't go back to the Version S7 Edge G935V.
However would I be able to convert it to one of the other carriers like T-mobile ?
You are the first that stated to check the EFS box.
With ODIN I will be choosing all 4 files but making sure I do NOT choose the HOME file, is that correct?
After flashing are there any other special instructions I need to do or will the phone right after flashing just
need to go through the normal setup along with possible adding the same APN config I am using with it on Straight talk w/ the straight talk AT&T sim?
thank you,
Ken
Click to expand...
Click to collapse
Yes you can go back to the stock verizon firmware.
There's two csc files in the firmware pack CSC_HOME will not wipe everything and the regular CSC wipes everything. You need to choose the regular CSC so it wipes everything. So backup your internal storage if needed. You may or may not need to manually enter your straight talk APN. Your SIM and APN should be detected upon first boot. Just make sure you choose the regular CSC file and not the CSC_HOME. You want to wipe everything and start fresh. If your APN doesn't automatically populate after flashing the rom then enter it manually. You should have no problems with this version of the U firmware.
G935V to G935U (AT&T)
If its written I have not found it yet but it would be nice to have a before and after as far as what you will gain and what you will loose after the firmware flash. It would cut down
on all the follow up questions, especially for me.
After flashing, you said I can return to stock firmware. Its strange I am reading you cannot return due to a BL that will not be compatible anymore with the Verizon firmware.
The G935V has been taking updates when it was on Verizon. Will this continue after changing it from a G935V (Verizon) to a G935U (AT&T) while on Straight Talk with their AT&T sim?
Does this G935U (AT&T) flash change any specific characteristics of the phone like its serial number and model #? I ask because the Samsung Smart Switch program besides
backing up your phone can also return it to stock (in case something corrupts it) and I am wondering if I give it the current serial# and model number G935V, will there be any problems since its model number firmware will be different.
I was advised when using ODIN under "Options" to check "Phone EFS Clear" . Does this still sound right. All other settings should stay as is.
Thank you,
Ken
tx_dbs_tx said:
Yes you can go back to the stock verizon firmware.
There's two csc files in the firmware pack CSC_HOME will not wipe everything and the regular CSC wipes everything. You need to choose the regular CSC so it wipes everything. So backup your internal storage if needed. You may or may not need to manually enter your straight talk APN. Your SIM and APN should be detected upon first boot. Just make sure you choose the regular CSC file and not the CSC_HOME. You want to wipe everything and start fresh. If your APN doesn't automatically populate after flashing the rom then enter it manually. You should have no problems with this version of the U firmware.
Click to expand...
Click to collapse
Q: After flashing, you said I can return to stock firmware. Its strange I am reading you cannot return due to a BL that will not be compatible anymore with the Verizon firmware.
A: When you flash a different U.S. firmware it has a bootloader included in the firmware. They can be flashed between the different U.S. firmware with no issue. the only time you may not be able to flash a firmware and bootloader is when you attempt to "downgrade your firmware to an earlier version.
Q: The G935V has been taking updates when it was on Verizon. Will this continue after changing it from a G935V (Verizon) to a G935U (AT&T) while on Straight Talk with their AT&T sim?
A: Yes, but the updates may not come as often as the carrier version of the firmwares such as Verizon, sprint, T-Mobile or AT&T. But you will get updates. It seems the carrier firmware will bring more frequent security patch updates than the "U" firmware.
Q: Does this G935U (AT&T) flash change any specific characteristics of the phone like its serial number and model #? I ask because the Samsung Smart Switch program besides
backing up your phone can also return it to stock (in case something corrupts it) and I am wondering if I give it the current serial# and model number G935V, will there be any problems since its model number firmware will be different.
A: No. The model#, IMEI, etc will not be affected. Only the software version will be affected as well as carrier specific update compatibility will be lost due to the "U" firmware.
Q: I was advised when using ODIN under "Options" to check "Phone EFS Clear" . Does this still sound right. All other settings should stay as is.
A: Yes. If you are having issues with network configs, you can choose to wipe efs so that it will rebuild upon first boot of the new firmware. This is only recommended if you have issues connecting to the network. Otherwise don't do it.
Since I'm on a roll I have another quesiton,
I dd a side by side comparison on this site
https://www.phonemore.com/compare/p...5u-vs-samsung-galaxy-s7-edge-sm-g935a/5532054
The phone called G935U has several more bands than the 935A (AT&T). Would this be a different G935U flash as compared
to the G935U (AT&T) ? If so would that not be the firmware to go with? It covers CDMA as well as GSM with the extra GSM bands.
This would be very similar to my G935V which offers CDMA and GSM.
Do I have it right NO CDMA capabilities on the G935U (AT&T) firmware?
Thank you for your replies its been very helpful. Its been a mystery trying to find out
what features you end up with with G935U and if their is a non provider version like in the above link.
Thank you
Ken
tx_dbs_tx said:
Q: After flashing, you said I can return to stock firmware. Its strange I am reading you cannot return due to a BL that will not be compatible anymore with the Verizon firmware.
A: When you flash a different U.S. firmware it has a bootloader included in the firmware. They can be flashed between the different U.S. firmware with no issue. the only time you may not be able to flash a firmware and bootloader is when you attempt to "downgrade your firmware to an earlier version.
Q: The G935V has been taking updates when it was on Verizon. Will this continue after changing it from a G935V (Verizon) to a G935U (AT&T) while on Straight Talk with their AT&T sim?
A: Yes, but the updates may not come as often as the carrier version of the firmwares such as Verizon, sprint, T-Mobile or AT&T. But you will get updates. It seems the carrier firmware will bring more frequent security patch updates than the "U" firmware.
Q: Does this G935U (AT&T) flash change any specific characteristics of the phone like its serial number and model #? I ask because the Samsung Smart Switch program besides
backing up your phone can also return it to stock (in case something corrupts it) and I am wondering if I give it the current serial# and model number G935V, will there be any problems since its model number firmware will be different.
A: No. The model#, IMEI, etc will not be affected. Only the software version will be affected as well as carrier specific update compatibility will be lost due to the "U" firmware.
Q: I was advised when using ODIN under "Options" to check "Phone EFS Clear" . Does this still sound right. All other settings should stay as is.
A: Yes. If you are having issues with network configs, you can choose to wipe efs so that it will rebuild upon first boot of the new firmware. This is only recommended if you have issues connecting to the network. Otherwise don't do it.
Click to expand...
Click to collapse
G935U Product Code USC vs. G935U (AT&T
Last night I flashed my G935U. It took 3 tries with the 3rd working after switching to a different ODIN reversion.
The phone works fine, no issues except I am disappointed I lost all the CDMA capabilities should I want to try straight talk with a Verizon sim.
After I flashed the file from the updato.com site I searched and found another G935U with Product Code USC. USA
https://updato.com/firmware-archive-select-model?record=05B44581906411E89F15FA163EE8F90B
A little more research and I found this is the unbranded version (correct me if I am wrong) The unbranded version appears
to retain CDMA plus have more GSM bands than the G935U (AT&T)
Could anyone offer some details on this firmware and could I have flashed this instead of the G935U (AT&T) to have retained
the CDMA and get more GSM bands.
Thanks, Ken
tx_dbs_tx said:
Ken, first check out the supported bands between the Verizon and the AT&T S7 edge in the link below. It will confirm the discrepancy in supported bands between the two models.
https://www.phonemore.com/compare/p...5v-vs-samsung-galaxy-s7-edge-sm-g935a/3296028
Then go to this link and download, extract and Odin flash the AT&T "U" firmware and see if that will open up the AT&T bands for your Verizon S7 edge. It very well might. I think you should also choose the option in Odin to "Clear EFS" before you flash so that it can be rewritten fresh upon bootup with your AT&T sim card. Do this and report back your results. Good luck.
https://updato.com/firmware-archive-select-model?record=0A1AF06A906411E89F15FA163EE8F90B
Click to expand...
Click to collapse
In my experience flashing another version will not add the bands. My case - I have flashed the "U" version on my "V" branded S7 Edge and the bands remained for Verizon. The modem firmware will read something that is flashed in the modem hardware and activate only those bands. There is a way to force other bands (see below).
More so, having the "U" Nougat, with modded LTE bands, I got the "U" Oreo upgrade from Samsung. After the upgrade to the "U" Oreo, the LTE bands reverted to the "V" ones (I had to re-enable them again).
I did "force" in the NV the new bands on my V using QPST and QXD professional Qualcomm tools, but since I don't really have a T-Mobile SIM I can't verify if the change works or it is something hardware (like RF amps) that is really missing.
How to: https://forum.xda-developers.com/galaxy-s5/general/how-to-add-rf-lte-frequency-bands-to-t2886059
The stock value for the "V" hardware, in the NV cell #6828 is 4190. That corresponds to LTE bands 2,3,4,5,7,13 (check with the LTE calculator).
I have changed the value to 2062440470751 that corresponds to bands 1,2,3,4,5,7,8,12,13,20,25,26,29,30,38,39,40,41 (close to what U would have natively). Again, I couldn't test if the software change is sufficient for them to actually work, but I have a feeling it does not.
When I traveled recently to EU, I have used cellmapper to check the LTE bands. I never saw B20, even if, on the map of that country, B20 was available in that rural location. I had only 3G.
G935U vs G935U
I posted the wrong link
This is the one I have my question on
https://www.phonemore.com/compare/p...5u-vs-samsung-galaxy-s7-edge-sm-g935a/5532054
This compares a G935U vs. a G935A
To get to the chase, what firmware would I flash to get the features of the G935U (left picture)
I just flashed my phone with the G935U (AT&T) and although it works fine with no AT&T bloatware it is missing
some of the GSM bands of the G935U (Left picture) and all of the CDMA bands.
Thank you,
Ken
Like I said above, the different firmware does NOT change the LTE bands.
KenKK said:
Last night I flashed my G935U. It took 3 tries with the 3rd working after switching to a different ODIN reversion.
The phone works fine, no issues except I am disappointed I lost all the CDMA capabilities should I want to try straight talk with a Verizon sim.
After I flashed the file from the updato.com site I searched and found another G935U with Product Code USC. USA
https://updato.com/firmware-archive-select-model?record=05B44581906411E89F15FA163EE8F90B
A little more research and I found this is the unbranded version (correct me if I am wrong) The unbranded version appears
to retain CDMA plus have more GSM bands than the G935U (AT&T)
Could anyone offer some details on this firmware and could I have flashed this instead of the G935U (AT&T) to have retained
the CDMA and get more GSM bands.
Thanks, Ken
Click to expand...
Click to collapse
G935U with Product Code USC is the "U.S. Cellular" network. I believe the way it works is the software will use the installed SIM to configure the network compatibility mode that will be available in network settings. The true "U" model of the S7 edge will have hard coded support for whichever bands samsung determines for that model number. The different versions of the "U" firmware are specific for whichever carrier/network the phone will be used on. I'm not sure which firmware would allow both GSM and CDMA networks to function simultaneously, but there is an app in google Play store called "network mode" and you could give it a try and see if it will open up simultaneous GSM/CDMA support in your network settings. I do know that Sprint's firmware does have GSM and CDMA support and I'm familiar with that because I have had sprint for nearly 10 years and have a lot of experience with the samsung software as I've built several ROM's including port ROM's over the past few years. Try the Sprint "XAS" firmware. That's the global version.
I have a S8 purchased as factory unlocked from samsung directly, which is U1 version.
Recently, I got notice from ATT about 3g shutdown, and I can see that S8 U1 does not support VolTE, but S8 ATT version does.
I know I can flash U1 to ATT version, but I have some questions
1) what is carrier switch?
I know there are 3 tutorial, flashing from carrier variant to unlocked, flashing from unlocked to carrier variant and carrier switch.
For my case, what is the different philosophy (not asking about steps) between carrier switch and flashing from unlocked to carrier variant?
2) can I keep my data while trying to resolve VoLTE issue? (carrier switch with Home CSC?)
3) Is there any way I can keep the bloatware-free OS while working with VoLTE (like unlocked AP + ATT CP hybrid)?
4) If carrier swithed to ATT with my S8, does it work with other sim card?
5) side question, I got a S20 from ATT, and I flashed it with U1 firmware, is it true unlocked version (I see ATT/ATT/ATT)? How can I make it true unlocked version. I am confused with the change of ATT/ATT/ATT and flashing firmware