Although updating your modem and/or bootloader is mostly a safe process, there could be dire consequences for not following the instructions.
I take no responsibility for any unexpected results or damage that may happen when following this guide! Also note, that updating your firmware manually might void your warranty!
Seriously speaking, I’ve used these guides more than once without problems, but if you still do encounter one, just ask and you’ll have all the support this thread can offer!
1. Post: Info, download links and video guides
1.1 Info on What and Why to update your Modem and Bootloader !READ!2. Post: Odin, Heimdal, FlashFire and Flashable zip guides
1.2 Latest Lollipop and Kitkat download links1.2.1 I9505 Download links1.3 Video guides
1.2.2 I9500 Download links
1.2.3 I9506 Download links
1.2.4 I9515 Download links
2.1 ODIN update guides3. Post:2.1.1 Updating modem & bootloader files on all variants2.2 Heimdall update guides2.2.1 Updating modem & bootloader files on all variants2.3 FlashFire update guides
2.2.2 Updating using automatic firmware packages2.3.1 Updating modem & bootloader files on all variants2.4 Flashable zip update guides2.4.1 Updating modem files on all variants
3.1 Downloading full firmware packages
3.2 Backing up and restoring your device’s data
3.3 Repartitioning and installing full firmware packages
3.4 Download links for latest PIT files for all variants
3.5 Creating flashable .tar files automatically using the MoBo script
(Currently only works for the I9505, will be updated)
3.6 Template for posting new firmware files
A SAFE Odin version can be downloaded from this thread
Heimdall can be downloaded from here
FlashFire can be downloaded from the PlayStore
Thanks to the developers!
1.1 Info on What and Why to update your Modem and Bootloader
A modem, sometimes referred to as a radio or baseband, is a driver that controls the sending and receiving of your mobile Network signals as well as switching between GPRS, 3G and HSDPA. It does not control Wi-Fi or the switch over between mobile signal and Wi-Fi. That’s the kernels job. There is no such thing as, "the best modem." It depends entirely on your location, operator and signal strength.
What is a bootloader?
In literal terms, the bootloader is code that is executed before your phones Operating System starts to run. Every Android phone has a bootloader that instructs the operating system and kernel to boot normally. Bootloaders basically package the instructions to boot the operating system and the kernel, and most of them also have their own debugging or modification environment. Basically, Android device is like a hard drive that has several partitions, which holds the Android system file in one and all the app data in another. And for all these partitions, Bootloader serves as a security checkpoint that is responsible for checking and initializing the hardware and starting software. Because if you’re able to swap out what’s on those partitions and you don’t know what you’re doing, something will break.
Why update your bootloader?
Updating your bootloader ensures you have the latest security and performance batches. Keeping it up to date can also drastically decrease boot time! If you have the wrong bootloader on the wrong OS (say, you have Kitkats bootloader and you updated to Lollipop) you might experience some problems. The bootloader might not know how or what to say to your kernel or doesn't even know what partition to look in, leading to some problems with things the kernel controls, like Bluetooth, Wi-fi and so on.
Why update your modem?
If your phone has to constantly search for signals and lock on to them, it not only gives you a poor call and data quality, but also drains your battery. It’s true, if you don't have any problems with your current modem, you don't have to update it. But in the other hand, latest modems (especially when used with the correct Android version) can improve your signal strength, decrease battery drain and might even increase performance! Up-to date modems also have the latest security patches, to keep the snoopers away.
What does GSM, NON-HLOS and COMBINED package stand for?
The GSM.tar file has the modem itself inside it. The NON-HLOS.tar (also referred as the Wi-Fi fix) is the LTE and Wi-Fi firmware. The COMBINED file just has both of these files together to make flashing more convenient.
Why some devices don’t have the NON-HLOS and COMBINED packages?
Some devices, like the I9500, don’t have the hardware necessary to use LTE. Thus it doesn’t have drivers for it and the Wi-Fi firmware is bundled inside the modem file.
What files should I flash?
Neither the modem nor the bootloader are dependant on your ROM. As far as the bootloader goes, always choose latest or the same as your modem version. Unfortunately the modem doesn’t play by the same rules. In general, later modem versions are better for reasons explained above, but some devices or regions simply don’t like some versions. So start from the latest modem version and if you get bad reception go down the versions until the reception gets better. (Give the version at least half a day to settle in.)
What do the letter-codes mean?
Example: XXUHPA1 for the I9505
XXU: is the region, in this case international.
H: is the android version, in this case ‘5.0.1’
P: is the year in alphabetical order, P is the 16th letter, thus 2016
A: is the month, again in alphabetical order, thus it’s January.
1: is the revision. In this case 1st
How to check your current Baseband / Bootloader version?
- Go to Settings -> About phone, see "Baseband version” # This is your modem version - Run in terminal: su getprop gsm.version.baseband # This is your modem version getprop ro.boot.bootloader # This is you bootloader version
1.2.1 I9505 Download links
I9505 Download links for Lollipop and up
GSM & NON-HLOS
Available from the post below:
GSM and NON-HLOS
I9500 Download links for Lollipop and up
I9506 Download links for Lollipop and up
GSM and NON-HLOS
More will be posted on request, or if someone contributes them
I9515 Download links for Lollipop and up
GSM and NON-HLOS
A HUGE thanks to the makers of these videos!
I’m sure they’ve made somebody’s day a lot easier
1.3.1 @droidblitz ‘s video for the I9505
1.3.2 @ISF ‘s video for the I9505
Donations aren't expected, but are appreciated! All donations will be directed to improve this, or some other of my projects here on XDA.
Hope I helped :3