Hello, I'm wondering if there is a guide or any info at all about rooting the KDDI's SGS3 LTE. I saw a bunch of thread for the NTT DoCoMo version but none about the KDDI version. No idea if they use the same hardware or not.
Root success by flashing CWM recovery and sgs3_rooting_supersu_v3.zip. Those tools are specified for Galaxy S3 NTT Docomo (SC-06D) but they also worked for Galaxy S3 Progre from AU KDDI (SCL21).
Just wondering how to unlock this SCL21, if anybody knows, please share.
brong said:
Root success by flashing CWM recovery and sgs3_rooting_supersu_v3.zip. Those tools are specified for Galaxy S3 NTT Docomo (SC-06D) but they also worked for Galaxy S3 Progre from AU KDDI (SCL21).
Just wondering how to unlock this SCL21, if anybody knows, please share.
Click to expand...
Click to collapse
I am also trying to find out a way to root my SCL21 but am having no luck. I have tried many of the "Universal 4.0.4 rooting methods" but have had no luck. Brong, would you mind sharing exactly what you did? The threads here http://forum.xda-developers.com/showthread.php?t=1999024 and here http://forum.xda-developers.com/showthread.php?t=1996940&page=2 warn about using the docomo method because it bricks the phone. Nothing seems to work with our model. Any help would be appriciated. Thanks.
madj1 said:
I am also trying to find out a way to root my SCL21 but am having no luck. I have tried many of the "Universal 4.0.4 rooting methods" but have had no luck. Brong, would you mind sharing exactly what you did? The threads here http://forum.xda-developers.com/showthread.php?t=1999024 and here http://forum.xda-developers.com/showthread.php?t=1996940&page=2 warn about using the docomo method because it bricks the phone. Nothing seems to work with our model. Any help would be appriciated. Thanks.
Click to expand...
Click to collapse
Hi,
First step is flash the CWM recovery via Odin. You can download CWM recovery from here:
https://docs.google.com/folder/d/0B...ZhbUE/edit?docId=0B98X7HyfoaGaNzNvR052dUp0Wmc
Choose this file: SC06D-JB-KBC-CWM-V6.0.1.2_r10-recovery-odin.tar.md5
Flash that file in Odin, choose the PDA in Odin.
I assume you already know how to flash via Odin, if you dont know just ask me again or try to browse other thread.
Step two is run the CWM recovery. Also, I assume you already know to get into recovery mode. Make backup first in recovery mode, you need to insert external SD card and save the backup in the card.
Step three, download this file sgs3_rooting_supersu_v3.zip from here:
https://docs.google.com/folder/d/0B...ZhbUE/edit?docId=0B98X7HyfoaGaR21wdXZweDdYSXM and save it to the external SD card that you used before.
Step four, run the recovery mode again and choose install from SD card, then choose external sd card and choose the file you donwloaded (sgs3_rooting_supersu_v3.zip). After completing all, reboot your phone and you will see the Super User app. Make sure you download root checker in Play store so you can check whether the phone are rooted or not.
Note: If you run the recovery, the screen will reverse. Dont worry, it works eventhough the screen reverses.
Thats all. I am looking the way to unlock this phone, *#197328640# doesnt work. If you have a clue, please let me know.
---------- Post added at 09:42 AM ---------- Previous post was at 09:27 AM ----------
madj1 said:
I am also trying to find out a way to root my SCL21 but am having no luck. I have tried many of the "Universal 4.0.4 rooting methods" but have had no luck. Brong, would you mind sharing exactly what you did? The threads here http://forum.xda-developers.com/showthread.php?t=1999024 and here http://forum.xda-developers.com/showthread.php?t=1996940&page=2 warn about using the docomo method because it bricks the phone. Nothing seems to work with our model. Any help would be appriciated. Thanks.
Click to expand...
Click to collapse
I see a Vietnam website with video on youtube. It shows that this phone has been unlocked.
http://choimobile.vn/threads/unlock-samsung-s3-scl21-au-kddi-nhat-ban.2699/
Any idea how to SIM unlock this phone?, really appreciate any help.
Thanks.
Updated:
I found a new thing regarding this phone. This phone doesn't support non LTE sim card, even you have micro sim (3G) card from AU KDDI. I am trying to find other LTE sim card from other carrier in order to check whether this phone works on that sim or not.
May be somebody can explain why this phone doesn't support non LTE sim. In case of Galaxy s3 LTE from NTT Docomo, it works when I used 3G sim (FOMA). I cut the 3G sim to fit the micro slot.
unlock for this phone
well, my purpose is/was to unlock this phone so I followed the samsung galaxy s3/note unlock method from here: http://forum.xda-developers.com/showthread.php?t=2014982
(I have/had this S3 Progre SCL21, the same phone in this thread)
I can access all the menu and procedure from that thread below, despite this phone being stock Android 4.04!
----------------
"Main Menu > [1] UMTS > [1] Debug Screen > [8] Phone Control > [6] Network Lock > Options [3]Perso SHA256 OFF > (after choosing this option, wait about 30 seconds, then go back one step by pressing the Menu button then select Back, now you are in [6] Network Lock then choose [4] NW Lock NV Data INITIALLIZ ..... wait for a minute then reboot your phone..."
---------------
I put 3G/2G sim card and the phone shows no service. I even put CDMA network sim, no luck. I don't know if this phone is unlocked. I'm wondering if this phone works only with LTE/4g sim. Right now, there's no 4G/LTE in my region
I assume the phone must support all other bands, if properly unlocked.
Now, I'm wandering through the threads and googling.
So far, I'm looking for Jelly Bean 4.1.1 for this phone, which doesn't seem to be available anywhere, even on samfirmware, only stock firmware
Root/flash CWM recovery and try some other unlock method from out there, (after making a backup Stock ROM and sensitive IMEI/NV data of course)
Please keep everyone updated and keep the spirit alive
aabhash said:
well, my purpose is/was to unlock this phone so I followed the samsung galaxy s3/note unlock method from here: http://forum.xda-developers.com/showthread.php?t=2014982
(I have/had this S3 Progre SCL21, the same phone in this thread)
I can access all the menu and procedure from that thread below, despite this phone being stock Android 4.04!
----------------
"Main Menu > [1] UMTS > [1] Debug Screen > [8] Phone Control > [6] Network Lock > Options [3]Perso SHA256 OFF > (after choosing this option, wait about 30 seconds, then go back one step by pressing the Menu button then select Back, now you are in [6] Network Lock then choose [4] NW Lock NV Data INITIALLIZ ..... wait for a minute then reboot your phone..."
---------------
I put 3G/2G sim card and the phone shows no service. I even put CDMA network sim, no luck. I don't know if this phone is unlocked. I'm wondering if this phone works only with LTE/4g sim. Right now, there's no 4G/LTE in my region
I assume the phone must support all other bands, if properly unlocked.
Now, I'm wandering through the threads and googling.
So far, I'm looking for Jelly Bean 4.1.1 for this phone, which doesn't seem to be available anywhere, even on samfirmware, only stock firmware
Root/flash CWM recovery and try some other unlock method from out there, (after making a backup Stock ROM and sensitive IMEI/NV data of course)
Please keep everyone updated and keep the spirit alive
Click to expand...
Click to collapse
So do I, It's hard to unlock
Thanh_GSM said:
So do I, It's hard to unlock
Click to expand...
Click to collapse
As its not a I9300 nothing from this forum is of use .
Suggest a Google search .
jje
Actually this phone, SCL21 can be used with LTE sim card only. I already tried to use non LTE sim card from KDDI AU with no luck.
What I am thinking is actually this phone maybe unlock-able by using the procedure as you mentioned (NW Lock NV Data INITIALLIZ). Since the phone can only be used with LTE sim card, we need to try LTE sim card from other carrier in order to test.
The problem is I dont have other carrier LTE sim card right now, if you have you can try it.
Update: Also I am wondering how to make this phone works with not only LTE/4G but also with 3G/CDMA. I changed the band to automatic, but there is no luck. I think this phone is locked to be used only with LTE/4G sim card. So, if somebody knows how to deal with this matter (make the phone not only accepts LTE/4G sim card, but also 3G/CDMA sim card) please share with us here.
aabhash said:
well, my purpose is/was to unlock this phone so I followed the samsung galaxy s3/note unlock method from here: http://forum.xda-developers.com/showthread.php?t=2014982
(I have/had this S3 Progre SCL21, the same phone in this thread)
I can access all the menu and procedure from that thread below, despite this phone being stock Android 4.04!
----------------
"Main Menu > [1] UMTS > [1] Debug Screen > [8] Phone Control > [6] Network Lock > Options [3]Perso SHA256 OFF > (after choosing this option, wait about 30 seconds, then go back one step by pressing the Menu button then select Back, now you are in [6] Network Lock then choose [4] NW Lock NV Data INITIALLIZ ..... wait for a minute then reboot your phone..."
---------------
I put 3G/2G sim card and the phone shows no service. I even put CDMA network sim, no luck. I don't know if this phone is unlocked. I'm wondering if this phone works only with LTE/4g sim. Right now, there's no 4G/LTE in my region
I assume the phone must support all other bands, if properly unlocked.
Now, I'm wandering through the threads and googling.
So far, I'm looking for Jelly Bean 4.1.1 for this phone, which doesn't seem to be available anywhere, even on samfirmware, only stock firmware
Root/flash CWM recovery and try some other unlock method from out there, (after making a backup Stock ROM and sensitive IMEI/NV data of course)
Please keep everyone updated and keep the spirit alive
Click to expand...
Click to collapse
Hi everyone ^_^
I just got the SCL21 about two weeks ago. I think it's really strange that even on the Japanese forums, there is very little info on rooting this model. From everything I've found, some Japanese sites also both say it's OKAY to root using the Docomo SC-06D recovery and Superuser zip while others say that it's NOT safe to use that same method and it will result in a bricked phone. Really odd, conflicting messages I think.
What is even more strange is the apparent issue with the screen "reversing"? One of the Japanese sites literally said the screen becomes "upside down" after flashing the SC-06D recovery.
Brong, since you got the root to work successfully , could you please elaborate on the "reversing" of the screen? Is the image upside down and only during the recovery mode? Also, do you know if the root caused you to lose the "osaifu Keitai" touch feature?
Thanks a lot to Brong and everyone else helping out with this model phone!!
Sent from my SCL21 using xda app-developers app
Status of SIM access
Hi,
I tested both a 3G micro SIM and a 4G LTE nano SIM from Softbank in this phone and neither card is recognized. The phone acts as though no SIM is inserted at all. (Complete with the "no smoking" symbol (circle with diagonal line through it) instead of a signal meter. I have confirmed that this phone is indeed sold already SIM unlocked from the factory as the MSL is 000000 just like the Verizon Galaxy S III which is also sold without a SIM lock. Additionally, KDDI lists the SCL21 and all other LTE phones they are selling since the debut last winter as being SIM unlocked devices.
According to some Japanese forums, they are suspecting that this phone has some type of hardware lock (hard locked?)... I contacted the only known person who was successful at using a 3rd party SIM on the Vietnamese Viettel GSM network as in a YouTube video. He wouldn't give me any details except that he must have the phone physically in his shop to modify it and it can't be done remotely. This individual also has screenshots showing the stock ROM version running in Vietnamese which makes me believe that he flashed something to the stock ROM to gain SIM detection of 3rd party cards.. Anyone have any ideas about such a hardware locking mechanism?
brong said:
Actually this phone, SCL21 can be used with LTE sim card only. I already tried to use non LTE sim card from KDDI AU with no luck.
What I am thinking is actually this phone maybe unlock-able by using the procedure as you mentioned (NW Lock NV Data INITIALLIZ). Since the phone can only be used with LTE sim card, we need to try LTE sim card from other carrier in order to test.
The problem is I dont have other carrier LTE sim card right now, if you have you can try it.
Update: Also I am wondering how to make this phone works with not only LTE/4G but also with 3G/CDMA. I changed the band to automatic, but there is no luck. I think this phone is locked to be used only with LTE/4G sim card. So, if somebody knows how to deal with this matter (make the phone not only accepts LTE/4G sim card, but also 3G/CDMA sim card) please share with us here.
Click to expand...
Click to collapse
decoding samsung galaxy s3 scl21
hello guys!!!! im a new member here ... i registered on this site for one reason and that is to help those people who have samsung galaxy s3 scl21 ... because i also got 1. I`ve been searching for months on how to unlock this phone so i could use it in my country (Philippines). I was almost loosing my hope because i was really eager to use this phone because of its features, a nice looking phone and its very expensive here in my country.
Few days ago i was browsing the net, i came across with this code *#197328640# that opened the window for me on how i could use the phone with any kind of sim card wether its LTE or 3G ..Im telling you guys the answers are all in that code
pinoyakooo said:
hello guys!!!! im a new member here ... i registered on this site for one reason and that is to help those people who have samsung galaxy s3 scl21 ... because i also got 1. I`ve been searching for months on how to unlock this phone so i could use it in my country (Philippines). I was almost loosing my hope because i was really eager to use this phone because of its features, a nice looking phone and its very expensive here in my country.
Few days ago i was browsing the net, i came across with this code *#197328640# that opened the window for me on how i could use the phone with any kind of sim card wether its LTE or 3G ..Im telling you guys the answers are all in that code
Click to expand...
Click to collapse
can you share step by step?
my phone need to unlock, please help
He's referring to the service mode. In that case, here are the steps to perform an unlock using the service mode (tested to work ONLY on the docomo models SC-06D and SC-03E; NO GUARANTEE IT WILL WORK ON THE SCL21):
1. Enter service mode by dialing the code in the dialer.
2. Press "UMTS".
3. Press "Debug Screen".
4. Press "Phone Control".
5. Press "Network Lock".
6. Press "Perso SHA256 Off".
7. Menu->Back (if the menu button turns up nothing, then just push "back") then wait 30 seconds.
8. Press "NW Lock NV Data Initallliz" then wait around one minute.
9. Reboot the phone and it SHOULD be unlocked. Works great on the SC-06D and SC-03E, no guarantees with the SCL21. And with the SC-03E newer basebands either hid it away or blocked it out so an older one needs to be flashed in before it will show up for unlocking.
Anyone looking to get one should only do so when they've got a trip to Vietnam in their future (to go get it done in a shop there; they still seem to be the only country with shops doing it) or be using au in Japan.
s3 scl21
that`s the first instruction i found when i was browsing the net and tried it but unfortunately it didnt work...... there are still settings in the service menu and all you have to do is click everything that has something to do with the wcdma to gsm..gsm to wcdma or g to wcdma something like that. There`s also a setting that tells somethin like resetting cant remember the exact word and you have to wait for 90 or 60 secs.and restart the phone .and then go back to changing gsm to wcdma .,there`s a setting also that you have to change the frequency .cant remember the step by step guide but because of my eagerness to use the phone i clicked everthing in the service menu and searched every command listed in there.(dont worry it will not brick your phone).After doing all that... this is what happened .. i thought i failed again because the no smoking sign was still there ...so what i did was i clicked the settings and i was so surprised that the menu for mobile network comes out meaning to say that i was able to unlock the settings on the network ..im telling you guys this is what vietnamese unlockers have been doing to unlock this phone that is why they need the phone physically....thats all thanks
And it never prompted for a SIM unlock PIN again? Somebody really needs to go through this carefully and document it; an SCL21 is only 24-25k yen in Japan; I've heard of people paying more to fix broken screens on their international/American S3s.
scl21
as far as i know this particular phone model (s3 scl21) from AU KDDI is not sim locked . The first time i inserted the 3g simcard, it didnt ask for a pin code or anything ...what i could see was the no smoking sign and the simcard icon is there in the apps menu.
it's diffcult to unlock... i can't use in my country... please help
pinoyakooo said:
as far as i know this particular phone model (s3 scl21) from AU KDDI is not sim locked . The first time i inserted the 3g simcard, it didnt ask for a pin code or anything ...what i could see was the no smoking sign and the simcard icon is there in the apps menu.
Click to expand...
Click to collapse
Hi im from philippine also. Please help me on how to unlock samsung Galaxy s3 progre scl21. Thanks in ADVANCE.
Please help
i need stock rom for SCL21 ...
Please help me link
help
pinoyakooo said:
that`s the first instruction i found when i was browsing the net and tried it but unfortunately it didnt work...... there are still settings in the service menu and all you have to do is click everything that has something to do with the wcdma to gsm..gsm to wcdma or g to wcdma something like that. There`s also a setting that tells somethin like resetting cant remember the exact word and you have to wait for 90 or 60 secs.and restart the phone .and then go back to changing gsm to wcdma .,there`s a setting also that you have to change the frequency .cant remember the step by step guide but because of my eagerness to use the phone i clicked everthing in the service menu and searched every command listed in there.(dont worry it will not brick your phone).After doing all that... this is what happened .. i thought i failed again because the no smoking sign was still there ...so what i did was i clicked the settings and i was so surprised that the menu for mobile network comes out meaning to say that i was able to unlock the settings on the network ..im telling you guys this is what vietnamese unlockers have been doing to unlock this phone that is why they need the phone physically....thats all thanks
Click to expand...
Click to collapse
can you list out the step you taken ? i have 2 phones.
Hi XDA ,
Am new in the Forum & First of all thanks to all of you for helping the forum and people. I'm having difficulties and I cant seem to find the way to fix this(its been 2 weeks)
My problem is the following: I have a Samsung Galaxy Note 3 details:
software version: N900PVPUBMI3
hardware version N900P.00
Status: network: Digital roaming
mobile network type CDMA-AxRTT
Android 4.4.2
KERNEL:[email protected]#1
A friend bought me this phone and called my carrier METROPCS and made them set up the phone so I could use it. they asked him for imei and sim number. He was able to use the phone and 4GLTE(he was doing this to verify it was unlocked) later on he gave me the phone and I had to do the same procedure he did but first I did a factory data reset.
After it I wasn't able to set it up again.
I've noticed that APN SETTINGS has disappeared from the menu, cant search for networks, when I load IMEI it no longer shows the imei but it shows MEID B0000000 and besides all of this I have a message that says SIM CARD INVALID.(but the sim card works perfectly on my other phone)
I will all my life appreciate if you help me with this matter please!
PS. phone is rooted as far as I know(root check on Google play store said it was)
Sir,
Please wait until mods will move this thread to the device specific forum for more relevant answers.
Stand by
Good luck
XDAGeorge305 said:
Hi XDA ,
Am new in the Forum & First of all thanks to all of you for helping the forum and people. I'm having difficulties and I cant seem to find the way to fix this(its been 2 weeks)
My problem is the following: I have a Samsung Galaxy Note 3 details:
software version: N900PVPUBMI3
hardware version N900P.00
Status: network: Digital roaming
mobile network type CDMA-AxRTT
Android 4.4.2
KERNEL:[email protected]#1
A friend bought me this phone and called my carrier METROPCS and made them set up the phone so I could use it. they asked him for imei and sim number. He was able to use the phone and 4GLTE(he was doing this to verify it was unlocked) later on he gave me the phone and I had to do the same procedure he did but first I did a factory data reset.
After it I wasn't able to set it up again.
I've noticed that APN SETTINGS has disappeared from the menu, cant search for networks, when I load IMEI it no longer shows the imei but it shows MEID B0000000 and besides all of this I have a message that says SIM CARD INVALID.(but the sim card works perfectly on my other phone)
I will all my life appreciate if you help me with this matter please!
PS. phone is rooted as far as I know(root check on Google play store said it was)
Click to expand...
Click to collapse
You might try installing this app it find/gives all the hidden info on your device http://forum.xda-developers.com/not.../app-one-click-hotspot-enabler-menus-t2816159 it will give you APN's MEID AND IMEI . All you have to do is download to your PC, it my download as a zip file. Just use 7zip and rename it to an apk, then copy and paste it to your internal sd card via your charging cable. Then click on apk and install. Enjoy !!!
BTW your MEID is on a label under the battery !!!
jimzweb1 said:
You might try installing this app it find/gives all the hidden info on your device http://forum.xda-developers.com/not.../app-one-click-hotspot-enabler-menus-t2816159 it will give you APN's MEID AND IMEI . All you have to do is download to your PC, it my download as a zip file. Just use 7zip and rename it to an apk, then copy and paste it to your internal sd card via your charging cable. Then click on apk and install. Enjoy !!!
BTW your MEID is on a label under the battery !!!
Click to expand...
Click to collapse
Hi Jim/XDA
I'm still not able to connect to the network. Regarding the IMEI on the back part i know its there however what im saying is that im not able to see my imei through command when i dial *#06#
i as well had this errors today when i woke up:
: LTE:ESM-x EMM-14(ive seen this error when this issue started but it dissapeared and it came back know)
data roaming: you have lost data connectivity because you left your home network with data roaming turned off.
On mobile networks i remember i use to be able to select many(GSM,CDMA,etc) now in network mode i only see 2 options LTE/CDMA,CDMA. Currently LTE/CDMA is selected and if you just look at the network mode option without actually opening it it shows CDMA/LTE/EVDO.
Also when i opened the SCRTN it shows on black screen.
I tried to do some minor changes on Galaxy tools like the SIM UICC UNLOCK all mps,sales,default code on XAS. Factory & keystring ON. MSL/SPC show 222222.
After i did SIM UICC UNLOCK and restarted phone know took away all errors but i see the signal bars faded out and with a little red x on top of it. I've read the manual but im still wondering if there might still be things to set on a particular way that are not specified on it Can you please help me set this up properly?
XDAGeorge305 said:
Hi Jim/XDA
I'm still not able to connect to the network. Regarding the IMEI on the back part i know its there however what im saying is that im not able to see my imei through command when i dial *#06#
i as well had this errors today when i woke up:
: LTE:ESM-x EMM-14(ive seen this error when this issue started but it dissapeared and it came back know)
data roaming: you have lost data connectivity because you left your home network with data roaming turned off.
On mobile networks i remember i use to be able to select many(GSM,CDMA,etc) now in network mode i only see 2 options LTE/CDMA,CDMA. Currently LTE/CDMA is selected and if you just look at the network mode option without actually opening it it shows CDMA/LTE/EVDO.
Also when i opened the SCRTN it shows on black screen.
I tried to do some minor changes on Galaxy tools like the SIM UICC UNLOCK all mps,sales,default code on XAS. Factory & keystring ON. MSL/SPC show 222222.
After i did SIM UICC UNLOCK and restarted phone know took away all errors but i see the signal bars faded out and with a little red x on top of it. I've read the manual but im still wondering if there might still be things to set on a particular way that are not specified on it Can you please help me set this up properly?
Click to expand...
Click to collapse
Is this a Sprint variant? If so, you shouldn't have factory reset the phone. It looked like the phone was previously flashed to MetroPCS and by resetting the phone, it removed all the carrier data.
You will have to reflash the phone to get it working again.
nature954 said:
Is this a Sprint variant? If so, you shouldn't have factory reset the phone. It looked like the phone was previously flashed to MetroPCS and by resetting the phone, it removed all the carrier data.
You will have to reflash the phone to get it working again.
Click to expand...
Click to collapse
Is there a tutorial i could follow here ?
I greatly appreciate your help,
Regards
George
Hey guys, for those who need to edit an APN (Access Point Names), there is a little secret.
Go Settings, and scroll down the list. You will find a search box. Type there Access Piont Names and here it is.
The steps above are neccesary, since APN setting is hidden.
So over a month ago,i flashed incorrect rom,and corrupted my imei,after flashing via odin i managed too restore my baseband and imei,however my imei was incorrect it was displaying as 35........6.
i learnt this is factory default
yesterday i discovered a method that has allowed me too connect too the mobile network once again,with corrupt imei.
i used service mode "root" via "Samsung info App"
option 2 : UE setting & info
option 1: setting
option 1: protocol
option 4: Sim
option 1: imsi replacement
option 1: om
then returned too protocol menu
option 2:Nas
option 1:network control
option 4:band
option 2:gsm
option 0:gsm all
end
Network function returned "only Edge works,but calling and sms perfect"
one problem,every time i restart have too re perform above steps
i was hoping someone could talk me through if possible how too automate fuction
thanks
Update I can connect too any network,as long as I connect either through gas or LTE, So I can H+ and LTE,network must be manually selected
Attached are photos I have made green dots on options that need too be set,this applies too them all besides the photo that contains LTE ,GSM ,HEDGE on that image green dots mean that that option will connect too mobile network but only one can be selected at a time,the red dots are not going too work they will display emergency calls only and not registered on network.
If you need and help just PM me and I can talk you through it
Samsung S6 edge
Hi, I have a Samsung Galaxy S6 edge with no imei. Can you telefon me what tools to use to recover my imei plecase?
Silekma said:
Hi, I have a Samsung Galaxy S6 edge with no imei. Can you telefon me what tools to use to recover my imei plecase?
Click to expand...
Click to collapse
How can it went missing?. Flashed wrong firmware?. There was somebody with imei issue managed to get back the imei after reviving his device using smart switch. Not sure how far it's going to help but worth to try.
Sent from my SM-G925F