yashsingh1/xdaforums huggingface dataset:
[Galaxy S II Original Android Development] Nebucatnetzer:
I googled a bit and even on a PC it's better to run v-sync. There are just to reasons why some should disable it.

1. PC is not strong enough.

2. You have a really fast reaction. Because v-sync causes a delay between the action of the user and the picture on the screen.

So the moral of the story stop disabling v-sync on any device unless you don't have enough power or you are a pro gamer.
[Galaxy S II Original Android Development] tolis626:
Well,you can only change mV by 25mV increments.The hardware(the regulator I think) accepts only values that are multiples of 25mV,thus any change by another number,say 30mV,isn't accepted.
[Galaxy S II Original Android Development] inkyadrian:
I will investigate. Thankyou
[Galaxy S II Original Android Development] programatix:
The refresh rate is the rate the monitor refreshes the screen from the buffer. Taking a monitor with refresh rate of 60mhz, it updates the screen every 0.1 second.

For example at the 0.01 second, an application update the video buffer with scene 1 and at the 0.08 second, it update the video buffer with scene 2. At the 0.1 second, the monitor will transfer the buffer to the screen, thus scene 2 is displayed and scene 1 is lost.

What happens if while the monitor is transferring the buffer and the application updates the video buffer? We get the tearing effect because part of the old scene is displayed and part of new scene is displayed.

V-sync is a method used to avoid the tearing effect. It does this by waiting for the monitor to refresh before updating the video buffer. This is the reason why we will get a 60fps rate if v-sync is enabled. However this is only true if the cpu and gpu are fast enough to finish drawing scenes, else the framerate will be below 60fps. If this happens, turning the v-sync on or off has no effect at all.

When v-sync is turned off, the application will keep updating the video buffer the moment it finishes drawing the scene. Thus turning off the v-sync make you see the real performance of the gpu and cpu.

Btw, on the kernel, I'm getting frequent reset with version 2.0.5 with bln. Anyone has this problem?
[Galaxy S II Original Android Development] mrabcx:
>Btw, on the kernel, I'm getting frequent reset with version 2.0.5 with bln. Anyone has this problem?

I will not say frequent, but I too had one or two resets in a day or two, so you are not the only one. Take copies of last_kmsg and post them up.
[Galaxy S II Original Android Development] pulser_g2:
None seen here.

If you are getting resets, make sure you reduced any overclock or undervolt, so you know it's not that causing the issue.
[Galaxy S II Original Android Development] programatix:
I'm running without overclock/undervolt. I suspect the BLN since that is what changed in the change log.
[Galaxy S II Original Android Development] sonic9:
+1, no issues here
[Galaxy S II Original Android Development] Major_Sarcasm:
I would look at other apps before you get suspicious about an app/service that doesn't seem to give others any problems.
[Galaxy S II Original Android Development] audino:
my friend

thank you sooo much for your work. im now running my i9100 undervolted at 800 mhz and its still lag free. the battary life exploded from 14hrs to 38hrs...
[Galaxy S II Original Android Development] CamoGeko:
Main cause of lock-ups and/or reboots on this kernel. :)

Had a few myself due to undervolting one step too much.
[Galaxy S II Original Android Development] programatix:
Well, since 2.0.4 (BLN enabled) never cause any reset problem, thus the reason why I'm guessing that it is BLN. Also, as mrabcx said it, my use of word "frequent" is actually wrong. So far in 3 days of using, I'm getting 4 reset, most of the time when accessing internet using Wifi.

Anyway, I'm going to try reverting to the original lights.i9100.so to see if I'm still getting the reset problem. Also, those who replied that they have no problem, I'm very grateful for the input but nobody mention whether they have BLN enabled or not.
[Galaxy S II Original Android Development] Lennyuk:
Most people on this thread will have BLN enabled and you are the first to say you have "resets". You just said that 2.0.4 was fine with BLN but you are still blaming BLN for problems with 2.0.5, this makes no sense.

Tell me, are these resets all the way to the "Samsung" screen or are they just to the boot animation of whatever ROM you are using?
[Galaxy S II Original Android Development] pulser_g2:
It could be related to the radio, if linked to the wifi as you say.

Try KH3 radio with this kernel? Failing that, revert the lights driver as you said.
[Galaxy S II Original Android Development] programatix:
Hmm, I wonder why almost everyone who responded to my question responded so aggressively. Nevertheless, the "reset" I mentioned is the one just like when you just power on the device from off state.

Furthermore, I'm not blaming BLN but I'm thinking that it might be related since the change log mentioned "Improvements to BLN battery usage". Also, I started the question to ask if anybody has the problem so that I can narrow down on any mistakes I might have done.

So far I know that at least one other user has the same problem as me.

Thanks for the advice. For now I reverted to 2.0.4. I'll try out with 2.0.5 later again when I have more time to spend on tinkering my phone.
[Galaxy S II Original Android Development] B3311:
I can't find my .tar image and my battery's rubbish, can I flash a new kernel over this one? Can I do this in Kies, and if not why not?

Also I can't be bothered looking for a bln tutorial, can someone tell me what to do instead?

And my Quadrant score is much worse than my friend's please fix

IMMEDIATELTY

dev!!!!!

C'mon, he's not here - we'll never get a better chance....

My little honeymoon gift to Hacre and missus. Chlamydia awaits!
[Galaxy S II Original Android Development] tolis626:
Dude,reading your post slowly made me furious.Same bull**** that's asked over and over again.To add to that,my nerves were ****ed up from something happening at home.I was readying my keyboard to reply to you in a post full of swearing(I couldn't help it).

Then I read the tiny letters.I burst out laughing. :p

You are so right dude.If someone wants to post bull****,now is their best chance to not end up in post 5! :D
[Galaxy S II Original Android Development] B3311:
Did you notice the spelling mistake in "immediately"? I didn't:o:o My strong and throbbing moral sense of values won't let me edit...

And why oh why oh where are the updates? How can he go off on honeymoon and not give us updates... Updates...Updates....
[Galaxy S II Original Android Development] pulser_g2:
Ahem... I can add to post 5 :D

You're not safe just yet :p
[Galaxy S II Original Android Development] pulser_g2:
Updates, you say?

I can give you an update that will stop you from asking for updates... :p Now... I wonder what would happen if we made a special super-fast kernel for you. 200 MHz voltage of 1.6V anyone?

The only thing that's fast about it is the speed the CPU will melt :D Then you won't need an update - you'll need a miracle :p

Or... I could make an update, that changes the version number to 2.0.1337. Then you can flash it and be happy :)
[Galaxy S II Original Android Development] Dr.C4nGr1:
Increible! :)

Thanks dude, is incredible my score in quadrant is 4015, wow dude! :D

thanks for your work.

http://twitpic.com/68mpgw
[Galaxy S II Original Android Development] inkyadrian:
My latest ROM:
[Galaxy S II Original Android Development] tolis626:
****... :mad: :p

What the hell are you dude?The Big Brother or something?That's Hacre's thread!He insults,he threatens to post-5 us,he promises(-not) updates.Stick by the rules,you 're a damn moderator! :p
[Galaxy S II Original Android Development] jerdog:
au contraire... one could argue that a damn moderator would be the best suited to update and "clean" the thread if an OP is on vacation.... :) :eek:

but describing pulser_g2 as "The Big Brother" does bring some chuckles to my head
[Galaxy S II Original Android Development] CamoGeko:
LOL, don't piss the man off or he will set Chuck Norris on yer ass... :mad::p

You know...some say "There is no chin under his beard, there is only ANOTHER FIST!"
[Galaxy S II Original Android Development] netarchy:
This is fixed in git (as of some hours ago when I got to it ;D), and thus should be resolved in the next released version.
[Galaxy S II Original Android Development] mentalinc:
Had my first reboot today. When i looked at my phone it was sitting at the enter SIM PIN. Not sure which reboot it was. Attached the lastkmsg.log below looks like a kernel panic then a reboot.

I had cleared dalvik cache, reset factory.

Flashed VR 2.4.2 and upgraded to 2.0.5.

Flashed modem (KH3).

As the only thing I;ve changed beside removing a pile of apps I don't need thanks to the reset is the new modem that is my guess on what the problem is.
[Galaxy S II Original Android Development] B3311:
You know I was in ironic mode I hope:)

In all seriousness, this kernel runs so smoothly for me that I have no idea how it could be improved.
[Galaxy S II Original Android Development] pulser_g2:
Indeed I do realise :)

<geordie>Today in the Big Brother house, geko95gek and the housemates decided to update the kernel on their phones. </geordie>
[Galaxy S II Original Android Development] netarchy:
*Points at the gpu clock control interface currently functioning on my sgs2 in a test build*

Coming soon™
[Galaxy S II Original Android Development] pulser_g2:
Haha nice one man :)
[Galaxy S II Original Android Development] AndreiLux:
This is what I've been waiting for! Excellent :D Did you guys figure out what internal voltage does?

PS: Oh and I hope you will be able to go LOW on GPU voltage, with Tegrak I used to go 750mV full stable even at 267MHz, and that was the lowest value inputtable, so I hope you'll make it possible to go lower as I'm curious what the lower stable limit is.
[Galaxy S II Original Android Development] tolis626:
Netarchy!Yay!Happy to see you here dude! :D

Out of curiosity,what was the problem?

F*ck yeah! :D
[Galaxy S II Original Android Development] tolis626:
I didn't think of that... :(

Pulser,pal,I am really sorry.Don't unleash Chuck,I'll be a good guy.I'll be eating all of my lunch,I'll be saying my prayers daily,I'll be brushing my teeth,I'll be providing useful last_kmsg.log's and I won't be asking for ETA's!But please,don't call Chuck! :eek: :D :p

Irrelevant fun

Have any of you played "Mike Shadow-I paid for it!"?If not,play it now.

Pulser,Chuck is on the specials list.He cracks the earth with his fist in fact. :p
[Galaxy S II Original Android Development] netarchy:
Needed an extra safety check to enforce a safety floor of 800mV. This check now will automatically change any attempt to set a voltage lower than 800 to 800 (ie; trying to set 750, for instance, will be auto bumped to 800 before the value is ever fed to the regulator).
[Galaxy S II Original Android Development] goldbergx:
so it is not possible to "set" the voltage to under 800 right? (say 751 mV?)
[Desire General] Futuredev.tjb:
Does anyone know of any roms for the CDMA Desire? I'm currently using MIUI which is great but wanna try something else. I've already tried CyanogenMod and Oxygen so any ideas
[Desire General] Jereso:
If you're looking for Gingerbread (2.3+) ROMs, those are really your only bet. There is no Sense ROM yet since there is no Gingerbread CDMA Sense base yet. There are a couple rooted Froyo Sense ROMs floating around Team US Cellular and 2fast roms.
[General Questions and Answers] speeed_demon47:
I've seen all the work you guys here at XDA developer do (and it's all really great).

And i'd really like to be able to develop stuff for android devices like you guys!

I know how to use Eclipse to develop apps and i've made a few apps already (no games or any real good stuff because i'm still learning right now).

But I want to be able to develop ROMs,kernels,...etc.U know!!

I've signed up for a java coarse at "New Horizons" training center and i'm gonna start in about a month.

But that won't teach me everything,it won't even teach me everything about application-creating

So,here I am,asking you guys (android developers):

How can I learn the stuff that you've learned?

What websites should I check out?

Where and how can I learn how to develop complete apps,games,Roms and kernels for any android smartphone?

In other words;Tell me how you learned all this stuff,and how can I learn it too?

Thank U!!!
[General Questions and Answers] Dark3n:
Custom ROMS are not created from scratch.

Existing ROMs from the manufactors are taken appart, dissected, modified and packed again to be uploaded here.

The best way to start on that is just by taking apart existing ROMs and looking through the files.

Modifiy some, repack them and check if it still works.

Repeat said process :-).

If you want to go deeper read up about decompiling & recompiling apk files.

Modifying bak smali code.

For creating your own kernels, just use google, so much info about that. Its not an android only topic, but a linux topic and the internet has plenty of info on that.

Good luck on your journy :-).
[General Questions and Answers] Quinity:
The first thing you have to do is to understand the system. This means you have to understand Linux, the kernel, the datasystem(because Android is obvisiously based on Linux).

You have to be able to understand written code or program/code yourself.

The best way to code for android is to learn java.

Read this here: http://developer.android.com/guide/index.html
[General Questions and Answers] speeed_demon47:
Ok,thanks for the information.

But let me tell you what I already know and understand:

Android is Linux,I know what linux is,I know everything about it and i'm already using GNU Fedora and Ubuntu (I have spent countless hours reading the "about Ubuntu" and "about GNU"),In Android or Linux everything is a file and everything in the system or the apps has a file .

Now I have some questions that I need you to answer first before adding anything else:

1-Is learning Java enough?don't I need to learn any other programing languages?And if I do,then what languages will I need to learn?

2-how can I learn to build or modify an android kernel (linux)?give me a good site or something?

3-how can i learn to decompile and recompile apks and roms?

4-What will I be needing to learn in order to buid a kernel?

5-What programing langusge is the android source code written in?I think it's java,am I right?

I hope you answer these questions before adding anymore information.

Thanks in advance,and I hope it's not any trouble:))
[General Questions and Answers] Quinity:
1-No, you need to compile and modify kernels etc. therefore you need to program in C(I guess)

2- Well, buy books about Linux and Kernels etc. Its quite difficult to teach it. You gotta learn yourself.

3- Decompiling and recompiling is not an option. Its like stealing - Dont modify apks without permission. If you got permission then you modify apks with the SDK(Java).

Roms are often compiled in C(I think)

4 - Books and the will to learn.

5. Android Source Code is C(like Linux), Android Apps are Java.
[General Questions and Answers] joohoo340:
Just making sure you mean c, not c# right??
[General Questions and Answers] Nilurun:
Try visiting the android website. There is a tutorial on how to get started with android development.

There is a fee that you would need to pay per year in order for your application to appear on the android market where you will be able to sell your product.

Java will be advantageous when it comes to android programming and if you know J2ME that will be a bonus as well.

ps:Learn from examples, buy a good book for beginners: “Hello, Android” and “Beginning Android“.

(i’m not a developer)
[General Questions and Answers] Dark3n:
I believe it is a one time fee when you sign up, not a yearly fee.
[General Questions and Answers] speeed_demon47:
Ok,I'm already using the Android developer website,but the whole thing takes time to read all the guidelines and do tutorials and packages.:(

So all i'm asking here:

What programming languages do I need to learn in order to be able to understand the native android source code and develop everything starting from kernel down to apps,I already know that I need to learn Java for apps and thanks to "Quinity" I know I need to learn C to understand the native source code.

I can easily learn C at any professional training center.The questions now are:

1-how and where can I learn to edit the Linux kernel and decompile and recompile ROM and APK files?

2-why do I even need to learn Java ME (formerly J2ME)?:confused:

I understand that Java ME is the java environment originally running on small devices with limited processors and performance such as mobile phones and smart phones,but what is the use of it when it comes to the app development,or any Android development at all?:confused:

And thanks for all the replies.:)
[General Questions and Answers] speeed_demon47:
One more thing,I have to make sure what the android source code written in.And Quick answers;PLEASE.

Is it C,or C#?
[General Questions and Answers] Dark3n:
C

Check out the wikipedia article, which states at the beginning:

The Android open-source software stack consists of Java applications running on a Java-based, object-oriented application framework on top of Java core libraries running on a Dalvik virtual machine featuring JIT compilation. Libraries written in C include the surface manager, OpenCore[21] media framework, SQLite relational database management system, OpenGL ES 2.0 3D graphics API, WebKit layout engine, SGL graphics engine, SSL, and Bionic libc.
[General Questions and Answers] speeed_demon47:
Thanks,the article really did help a lot.

So,now I need to learn Java SE (without question),but what about Java EE and Java ME,will they be useful in the app development process,will I need them?

And what If I can't learn C (it's extremely hard to find a training center that teaches C these days),will learning C++ or C# do me any good?

I know that the source code is written in C,but is it really a big difference between the three,If I learn C# or C++ will I still be able to do everything I need to do and fully understand the code?

note that i'm on a tight schedule for now and I need to learn only the stuff I can't do without.
[General Questions and Answers] Dark3n:
I think you are missunderstanding something here.

You should start by just learning java, the different EE ME SE etc. are still java.

The difference is that those are sets of java platforms. They bring, as does the android platform, prebuild libaries along, these contain functions (i.e. print that, create datastructure X) so you don't have to write every tiny bit of code.

Forget about those.

You want to use java on the android platform, which still uses java, but brings along its own libaries with prebuild code you can use ( See http://developer.android.com/reference/packages.html ).

So just learn java, if you want to work with android you can learn java on the android platform, this way you will already be familiar with the libaries provided by android.

I would say C# is more similar to java and C++ is more similar to C.

I don't understand what you mean with "do everything i need to do".

What do you need to do?

"Understand code".

Understanding code does require more than knowing what each line does, you will have to see the bigger picture ,not just few lines of code, to understand what is does. Depending on how the code is written (tidy or confusing), is the code commented? It might take ages to understand it.

Programming is sometimes a bit like art :-). Code can be beautiful or horrible :p

You don't have to do everything in a training center either.

The internet, time and interest is enough. There are so many tutorials and pages available...

You could have also found most of the answers by just using google...

Wikipedia article about java holds the information about the differences between EE/ME/SE etc...

Searching for terms like "difference C C sharp" etc. holds the answer to that question...

So maybe a training center is better for you to learn those programming languages, as "google skills" will certainly be required to teach you those things yourself.

What tight schedule are you on?
[General Questions and Answers] speeed_demon47:
Yes,I already know all about java,I read the articles on wikipedia,but why would I need to learn java enterprise? Isn't it mostly used around internet applications and servers? Can't I just use the APIs if i'm going to build an app that needs internet or server connectivity?

And why would I need to learn java Micro? Doesn't android use dalvik virtual machine to run apps? I mean,java Micro is mostly used to create feature phone apps,why would I need it with android?

There's something I don't understand though,on wikipedia the article about android says this:"Applications are usually developed in the Java language using the Android Software Development Kit, but other development tools are available, including a Native Development Kit for applications or extensions in C or C++"

So,the question is;what is the difference between apps developed in java and apps developed in C or C++?

The problem about C# is that I don't know anything about it;can't find any articles on wikipedia and other sites really don't help!!!

I meant by "understanding the code",having the ability to understand the command lines,what they do,what each line is responsible for and having the ability to edit or adjust something,.....etc.

And for the tight schedule;I need to learn everything about android within 6 months (I don't need to learn C as much,but it'd be a bonus),and that's why I go to training centers,faster and more efficient than self learning.

What did u mean by "google skills"?

And what did u mean by "learn java on the android platform"?

Thanks for the help and providing quick answers.
[General Questions and Answers] Dark3n:
You miss understood again... :D

I will try to be clearer:

I meant by google skills, that you would find most answer yourself if you just use a search engine with the right terms.

You DONT need to learn Java ME/SE etc.

You can and will only use the APIs provided by the android toolkit.

So if you already know java, google "android developement tutorial" and start build some apps to get experience.

Forget C#, you don't need that, AT ALL for android.

Android apps, only need java.

If you want to understand the deeper layers of android, those are written in C.

But "int i=0;" is a variable i with value 0 in java and in C. So if you just want to read some of the code of the deeper layers and change small bits, you don't need to take extra courses in C.

So the conclusion is, you need to understand the android architecture and be able to write apps and have experience...

I would recommend to just think of some thing and write an app for that, learning by doing. Occasionally you can read some theory about the underlying concept of what you are doing.

An example would be to write an app that sorts values the user enters.

You would use already premade sort and array functions from the android api

Something like

Array x;
x.addAll(y);
x.sort(Descending);

To get deeper knowledge you could then browse the android sourcecode and see how x.sort actually sorts the array.
[General Questions and Answers] HuTcHx:
I think Android application is writen in Java ?

But maybe it is not that your question?