SM-G930P on AT&T - AT&T Samsung Galaxy S7 Questions & Answers

I've got a Sprint variant, SM-G930P, it is running SM-G930U firmware on AT&T network. My question is am I missing out on any bands? I know the different carrier variants list different bands, I've read that this is all firmware controlled and every US model has the hardware to support every band, but haven't seen a definitive answer on if the bands supported are changed when flashing a carrier rom.
MOD EDIT: DUPLICATE THREAD CLOSED

Related

Unlock all lte bands on S7 Edge(Verizon)

Hi Guys,
I have read lot of comments & QA's, still i have no clarity.Some one please clarify me.
If i buy S7edge Verizon (Sd820) can i use it in india.Verizon bands are 2'4&13. However i heard that verizon lte phomes are unlocked. Can i use in india lte network(Jio or Airtwl LTE network.
However locking is software thing(firmware), can i install international firmware (935U , not sure) to unlock all lte bands, to use any simin world....
Indian lte bands.
TD LTE 2300Mhz
FD LTE 1800Mhz
Please help
http://forum.xda-developers.com/showpost.php?p=68194338&postcount=2
you have to add lte bands by qxdm method or you shouldn't buy the varizon device.
satish.yarramsetti said:
Hi Guys,
I have read lot of comments & QA's, still i have no clarity.Some one please clarify me.
If i buy S7edge Verizon (Sd820) can i use it in india.Verizon bands are 2'4&13. However i heard that verizon lte phomes are unlocked. Can i use in india lte network(Jio or Airtwl LTE network.
However locking is software thing(firmware), can i install international firmware (935U , not sure) to unlock all lte bands, to use any simin world....
Indian lte bands.
TD LTE 2300Mhz
FD LTE 1800Mhz
Please help
Click to expand...
Click to collapse
Decided to pull the trigger and do this following a guide on Youtube. I used firmware G935VVRU2APD2 and followed this how-to https://youtu.be/WVzXvMa5FQ4 and everything worked out perfect.

Yotaphone 2 Frequency and Radio Firmware - AT&T

Hey guys -
So like many of you, I reflashed my two Yotas to the latest RU Lollipop and was wondering if there was another radio firmware file that might wake up the AT&T US LTE bands. Any thoughts? Has anyone tried flashing the different radios to see if you can get a 4G LTE signal stateside?
Thanks,
Rootdude
what upload/download speed do you have now?
YotaDevicesRussia said:
what upload/download speed do you have now?
Click to expand...
Click to collapse
I have HSPA+ on AT&T . Can you help us with US modem firmware for LTE?
ivanupolo said:
I have HSPA+ on AT&T . Can you help us with US modem firmware for LTE?
Click to expand...
Click to collapse
HSPA+ can be sometimes very good - 3-15Mb/s - what is your speed at the moment? can you check through speedtest.net ?
At&t firmware
I have around 3.5 mbs to download and 0.6 uploaf. Too small comparing local 4G. So, can you help us?
I do not think you can change that easily, there's a thread talking about changing Radio Bands but the conclusion I got from the reading is that it does not work, at least with current "user" knowledge, YD206 is from China or HongKong, and some of those LTE Bands can work in Europe, not so much on the USA, the bands that USA telephone companies are very different than Europe or Asia, and as such YD206 IS NOT compatible with USA LTE bands. UMTS can have much higher upload speed than the ones you posted, so it might be your network problem, don't know if they are any better in LTE over your region.
Should be possible
Qualcomm 8974 supports all LTE bands. We just need proper modem firmware for US bands. Method in those threads definitely doesn't work since Qualcomm introduced some hidden filters inside firmware
BTW, there is lte_prefferedband file in the modem folder of Yota EFS. Does anyone know how to edit it?
That might be a anti-tampered code against our NV changes
Ok, I found out. For AT&T we need qcn file from Yotaphone 2, model 205. I don't know it such thing exist on the market but this reference says that it might be compatible with At&T.
https://www.frequencycheck.com/models/A1JaO/yota-yotaphone-2-yd205
ivanupolo said:
Ok, I found out. For AT&T we need qcn file from Yotaphone 2, model 205. I don't know it such thing exist on the market but this reference says that it might be compatible with At&T.
https://www.frequencycheck.com/models/A1JaO/yota-yotaphone-2-yd205
Click to expand...
Click to collapse
interesting thing is that YD205 model was never launched, so it doesn't exist at all, unfortunately. The inquiries about future developments of this model were negative...

Question: Flashing SM-930A to SM- 930V unlocks Verizon bands?

I apologize, I tried searching for this, but I couldnt find the answer.
Out of curiosity... if I flash my AT&T S7 Edge with the Verizon stock Rom, will that unlock all the necessary bands needed to support a Verizon simcard?
No, the AT&T S7 is missing the CDMA bands that require to run on Verizon. You would have to get either the 930V or 930U variants.
xtk said:
I apologize, I tried searching for this, but I couldnt find the answer.
Out of curiosity... if I flash my AT&T S7 Edge with the Verizon stock Rom, will that unlock all the necessary bands needed to support a Verizon simcard?
Click to expand...
Click to collapse
It will unlock the Verizon bands, I can personally confirm this. CDMA part gets activated too. All US S7s have the CDMA portion, its the firmware that enables or disables CDMA. For example, if you flash the T-Mobile/AT&T firmware on a Verizon or Sprint S7, the CDMA is disabled by the firmware and if you flashed the Verizon/Sprint firmware on an AT&T/T-Mobile S7, the CDMA portion is enabled by the firmware. The US unbranded Firmware has the GSM/CDMA portions enabled by default.
micallan_17 said:
It will unlock the Verizon bands, I can personally confirm this. CDMA part gets activated too. All US S7s have the CDMA portion, its the firmware that enables or disables CDMA. For example, if you flash the T-Mobile/AT&T firmware on a Verizon or Sprint S7, the CDMA is disabled by the firmware and if you flashed the Verizon/Sprint firmware on an AT&T/T-Mobile S7, the CDMA portion is enabled by the firmware. The US unbranded Firmware has the GSM/CDMA portions enabled by default.
Click to expand...
Click to collapse
I went from 930a to 930v, it works fine firmware wise but is constantly roaming. Do you have this issue?
Jeff545454 said:
I went from 930a to 930v, it works fine firmware wise but is constantly roaming. Do you have this issue?
Click to expand...
Click to collapse
Not sure to be honest, my carrier is gsm only so i dont use the verizon firmware on mines.

Sm-g935u oreo

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.

Specification need for G935U vs. G935U (AT&T)

https://www.phonemore.com/compare/p...5u-vs-samsung-galaxy-s7-edge-sm-g935a/5532054
This compares a G935U vs. a G935A
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
Unless your phone is a true "U" unlocked model, it will not have the same bands as each of the specific carrier variants such as the AT&T variant. I've never confirmed if flashing a different firmware and modem (CP file) will open up other bands on a carrier branded phone. Maybe someone else has tested this and can offer their input. I tend to doubt it's possible because i think the bands are hard coded onto the chipset thus making it virtually impossible to "activate" unsupported bands on any given model. good luck.
Nope, the modem bands are not changed by the firmware flashing. I have flashed "U" firmware over my "V" phone and it still had only the "V" bands. This is similar to all Snapdragon radio modems - it happened the same way on my older moto and Asus phones too.
The bands can be software forced "on" by flashing the Qualcomm NV memory (with Qualcomm tools) but, in my experience, they will still be not be working. More, at every official upgrade, the "old" value of the NV is reset to original hardware bands.
I have flashed my 935V with 935U (AT&T) firmware and besides the no more bloatware I do
get bands LTE 12 and 30 for sure that I did not get with the 935V when in the GSM mode.
Ken
SoNic67 said:
Nope, the modem bands are not changed by the firmware flashing. I have flashed "U" firmware over my "V" phone and it still had only the "V" bands. This is similar to all Snapdragon radio modems - it happened the same way on my older moto and Asus phones too.
The bands can be software forced "on" by flashing the Qualcomm NV memory (with Qualcomm tools) but, in my experience, they will still be not be working. More, at every official upgrade, the "old" value of the NV is reset to original hardware bands.
Click to expand...
Click to collapse
I know for sure that flashing the U over V did not change the bands on my phone (not the A firmware), the NV value remained (reverted) to the original bands. Did that even after the OTA Oreo upgrade of the Nougat U version.
Cell #06828 has the value 4190 on the V version of S7.
If you use the LTE Band Calculator you will see that's 2,3,4,5,7,13.
Can you post a service screen with that working (dial *#0011#)?
LE: I stand corrected. The U firmware re-flashes the modem's CSC file with every change of the SIM. In that process it activates ONLY the bands needed for that CSC - this includes the 2G, 3G and 4G/LTE. This is unlike any other Android phone, where the bands are always the same.
There are other things affected by this file, for example the APN, or the accessibility of the Service menu (*#0011*) or the menu to view/change the LTE bands (*#2263#).
With a Tracfone/Verizon SIM, I get only the Verizon bands (except 66 that is not supported) and a couple of international ones. The flashed CSC file is TFN.
With a AT&T SIM, I get a lot more bands, including all AT&T (except 14 and 66 that's not supported) and international ones. Flashed CSC file is ATT.
With an international SIM (Vodafone), flashed CSC file is XAA.
The U firmware has available the following CSC codes: ACG, AIO, ATT, BST, GCF, LRA, SPR, TFN, TMB, TMK, USC, VMU, VZW, XAA, XAS.
More here: https://forum.xda-developers.com/ve...ge-verizon-firmware-modded-lte-bands-t3827369

Categories

Resources