Database Develop

SLCD Nexus One

So!
Yesterday was an eventful day for me. I got my Nexus One with FRF91 shipped on it and started rooting it. By about 7pm, I had an unbootable device that would load the X symbol at the beginning but then gave a black screen for recovery and the main ROM itself.
If I slid my finger across the screen, I felt the unlock vibration. Turns out, I had put a boot.img on the phone for a AMOLED device and Vodafone had given me an SLCD device!
Eventually, I managed to get Amons SLCD recovery on there and got the shipped FRF91 Korean ROM (Vodafone one wouldn't apply).
I now have my phone in a working state again.
What I want to know, and this is to all the Nexus One devs, is it possible to crack open the stock ROM that has SLCD support and implement this support into your ROMs. So basically as an example Cyan could make an AMOLED version and a SLCD version.
The theory behind it seems like it should be straight forward. Surely it someone could put something together. Perhaps Paul @ Modaco or Cyan could try and just whack together a non root custom ROM just to see if it's possible.
Alternatively, if one of them gives me the guidance, I'll do it myself but I figure more people will test theirs than mine
What does everybody think?

The commits are there, you just need it compiled in the kernel.

Exactly, I just have no idea how to do anything like that! Haha.

I am from the U.S. and I just got my N1 replacement under warranty. After comparing with my existing one I determined that my new replacement is the SLCD version. I guess I gotta be careful with flashing custom ROMs....

will be possibly running into this issue myself tomorrow, as my replacement is scheduled to reach me. Any easy answers for us SLCD guys who love our CyanogenMOD?

God I hope I don't speak out of line, but I believe the nightlies since mid August support SLCD. Don't know if that includes CM 6.0 stable.

CM6 and nightlies support SLCD. The newer nightlies now support the new HBOOT (that seems to come on the newer devices). CM6 you may need to find a modified version (link somewhere in cyanogen forums or in these forums) if you end up having a newer HBOOT (0.35.0017). Evil's NXSense also has SLCD support. Rest I can not vouch for. Kang-O-Rama didn't have SLCD support though I think the creator of that ROM was working on a new version which will include a different kernel which might have SLCD support.
Other than that you need to be sure to use Amon_Ra 1.8.0.1 or PSFreedom 1.1.1 as those are the only 2 recovery images I know of that have SLCD support as of now. This means you can not use Clockwork for your recovery.

[Q] Kernel vs ROM

XDA has a wealth of info, but it does seem to assume that you are already pretty knowledgeable about many of the subjects. I'm brand new to this. I've been reading a lot, but still feel like I'm missing some basics. One question I can't seem to find an answer to is: What's the difference between a Kernel and a ROM? TIA for educating me

Espaa Valorum said:
XDA has a wealth of info, but it does seem to assume that you are already pretty knowledgeable about many of the subjects. I'm brand new to this. I've been reading a lot, but still feel like I'm missing some basics. One question I can't seem to find an answer to is: What's the difference between a Kernel and a ROM? TIA for educating me
Click to expand...
Click to collapse
A ROM is a collection of all your services, phone, sms, bluetooth, applications etc. bundled in a flashable zip or sometimes odin flashable packages. Think of it as a customized operating system. Which it is. Some are themed, some are not.
One thing that every ROM has included is a kernel. The kernel is the interface between your gui (You basically) and the hardware of the phone. The "brains" as it were. When you touch a widget (or whatever) on your screen and something cool happens it's because said widget passed a request for action and the kernel tells the hardware involved to get busy.
Oversimplified, but I hope it clarifies some.

It's not the greatest metaphor, but a ROM is Windows, and a Kernel is your BIOS.

MikeyMike01 said:
It's not the greatest metaphor, but a ROM is Windows, and a Kernel is your BIOS.
Click to expand...
Click to collapse
heading in the right direction but a bit off.
The kernel is the operating system.
The rom is a collection of software that includes user gui and some of the software for hardware to operating system interface.
Windows is actually both a kernel and user gui.
A bios is nether - usually bios is just hardware firmware - but sometimes contain a few other things as well.
The best example from a pc would be a linux distro such as ubuntu - the desktop environment gui ubuntu/gnome would be the " rom " and actual linux operating system running underneath is the kernel.

Alright, thanks for the explanations, it is a little clearer now.
When i got my phone i did the OTA update to JH7, rooted, installed Clockwork and did a ROM backup. So i have that backup saved. I want to try some other tweaks and such that i see mentioned around here all the time, but i wanted to make sure i understood the various pieces before i start messing with it all any further. So having the ROM backup, i should be always be able to get back to the state of the phone at that point right? (I understand it does not include pictures and messages and such.)
I guess what i haven't been able to find is a newbie guide that explains how to start at stock, what steps to take, what to actually do with the backup, how to restore etc. So i'm trying to learn. Thanks for the replies, it helps!

No. going back that way will not always work.
Make sure you can get into download mode, recovery mode, and that your computer is recognizing your device.
If you are flashing roms, at some point you will need odin so this is essential that you can get that to recognize your device in download mode to flash back to stock when something goes awry.
Sent telepathically using vulcan mind meld app.

I was able to get into recovery mode. I did the rooting through an update.zip. My computer also sees my device fine. I used ADB to communicate with it (and remove the market restriction.) I'm on a Linux box, and it seems that Odin is a Win app?

Technically windows has a kernel too, most people just don't talk about it.
Hence the ROM being the whole package as mentioned above is a good metaphor
Sent from my SAMSUNG-SGH-I897 using XDA App

More kernely details
I hate to revive an old thread, but this one is exactly on a topic I am currently researching. Being a noob I have read a lot over the past couple of weeks but am still a little confused about this whole kernel thing.
I know what the kernel does. What confuses me is that I have seen several references (including in this thread) that a ROM will always include a kernel. If that is the case, why is it that some ROMS state "does not come with a kernel" and ask you to flash the "kernel of your choice".
With this in mind I would like to know:
-How can I tell what kernel I am running? Is it the "build number"?
-Since the kernel does not present anything the user actually sees, how could you possibly choose a kernel and like one over the other?
Thanks!

think of it this way...
the rom is a car (the whole thing)
the kernel is the engine (engines have performance options or economy options)
the build (eg 2.1 /2.1 /2.2.1 or 2.3.3 is like the model of car shape, options ect)
the theme is the interior and exterior options. (the looks)
add-on zips such as dialers/battery mods are like aftermarket accessories.
- copyright tristyn russelo 2011
Click to expand...
Click to collapse
to tell what kernel you are on;
menu button > settings >about phone > kernel
to know about each kernel go to the XDA > Captivate > Development area look for [Kernel] at the beginning of each thread. look at the options, read the options, research the options
also there IS visible features of the kernel if it has ClockworkMod Recovery built into it. with this you dont need ROM manager or the update.zip method of Clockwork Mod Recovery (aka CWM)
see the CWM onix kernel idiot guide in my sig.
and check out the XDA wiki for ClockworkMod Recovery. "i started it"
also check out the http://Capfaq.com

TRusselo said:
think of it this way...
the rom is a car (the whole thing)
the kernel is the engine (engines have performance options or economy options)
the build (eg 2.1 /2.1 /2.2.1 or 2.3.3 is like the model of car shape, options ect)
the theme is the interior and exterior options. (the looks)
add-on zips such as dialers/battery mods are like aftermarket accessories.
- copyright tristyn russelo 2011
Click to expand...
Click to collapse
Click to expand...
Click to collapse
That's a great explanation, thanks!

Thanks, Tristyn for that analogy. So my question is, can you just use a "Kernel"? By Tristyn's analogy, it appears that just the kernel is useless as you can't drive a car that only includes the engine (ie: you need the wheels and the frame, etc.).

What? if you flash just a kernel it doesn't delete the framework? It's just like swapping the engine in a car.
Yes if you SOMEHOW only had a kernel installed you get a boot error and it would probably give you the "phone...!....pc" screen.

i added that analogy to my new users guide the other day but expanded...
- "A ROM" is like "a car" nothing in specific but a body, wheels, engine, and paint. a general standard vehicle.
- "Each ROM" or each developer is like an auto maker. Each has their own style, options, focus and customer base. Some are luxury, others economy and some are fully loaded! Some are fully packed and heavy and others are base models and very light. You get to get to choose what you like or need, and for once "price is no object" (donating is appreciated) But you almost always get a whole car!
- "Framework" or "Build" - is like the frame of a car, you cant put SUV parts in a Honda. It just won't work unless you rebuild from scratch (and if you can do that, you would laugh at this analogy!) Parts / Kernels / Mods must be compatible with that framework and that framework must be compatible with your phone.
- "Rooting" or getting a "rooted ROM" is like getting the keys and permission to change ANYTHING in your car! But you dont have a warranty anymore!
- "The Kernel" is like the engine and power systems, it is the "software" engine, it does work and ties all the components together. And engines can be upgraded and tuned up for performance or down for economy!
- The theme is like the paint job. pure looks and enjoyment!
- Other dialers, meta-morphs, mods ect are all after market fun changes, once again only looks not usually any more function.
- The launcher (no rooting or romming needed) is alot like your interior, its the seat you sit in and the controls you touch 75% of the time, until you dig through your glove box or fuse box (back to rom)
Click to expand...
Click to collapse

TRusselo said:
i added that analogy to my new users guide the other day but expanded...
Click to expand...
Click to collapse
Haha very nice Tru! I love it

Sorry to ask repeative questions of Kernel & m0d,
but i failed to understand few Things
1. Whenever we are installing a m0d {like cyanogen, oxygen, etc} iS iT necessary to install another kernel ??? oR can we just run on Stock kernel
2. if we install another kernel can we get back our stock kernel ?
3. Do m0ds come pre-installed wid kernel or do we need to install them seprately.
4. h0w would i know that which kernel is made for which rom ???

If you go to CyanogenMod 7 for Captivate Q&A ( gotta love the search function ) and read the devs OP pretty much all your questions will be answered, infact any rom you care to flash if you read the devs OP they will spell out what you are asking for.

Custom ROM and then a custom Kernel. Is it possible?
Well, I'm a bit confused. Consider this:
I flash the phone with CM7(say). Here I'm assuming that CyanogenMod comes with its own kernel. My question is: Can I flash a custom kernel on top of this setup? and what difference does it make?
One can also think the other way round. I have flashed my phone with a custom kernel. Successively I flash CM7 on to my phone. What happens then? Is the original custom kernel wiped out to be over-written by CM7 kernel? What can be done to keep it intact? Please people solve this dilemma...

saurabh.khare1000 said:
Well, I'm a bit confused. Consider this:
I flash the phone with CM7(say). Here I'm assuming that CyanogenMod comes with its own kernel. My question is: Can I flash a custom kernel on top of this setup? and what difference does it make?
One can also think the other way round. I have flashed my phone with a custom kernel. Successively I flash CM7 on to my phone. What happens then? Is the original custom kernel wiped out to be over-written by CM7 kernel? What can be done to keep it intact? Please people solve this dilemma...
Click to expand...
Click to collapse
It's not really a dilemma. You can flash any appropriate kernel that you want. Flashing CM7 again will give you the CM7 kernel. Simply reflash your other kernel.
My post here explains why you may want to switch
http://forum.xda-developers.com/showthread.php?p=26110276
Swyped from my ICS Samsung Captivate

[Q] How to get started making captivate roms

Hey Guys,
I'm a developer for a living, and I'm interested in possibly working on a custom rom for my captivate. I was doing some research on how to get started, but the stuff I found was for HTC phones and involved using a starter that only works for HTC stuff.
Where can I go to find information on doing this? I'm largely interested in trying to port gingerbread, but my understanding was that until we have the full source this wasn't really possible (at least for something actually useable on a daily basis). I see supercurio is working on gingerbread, so information specific to this would be really helpful.
Thanks guys, and sorry if this should have been put in the QA section, I figured it was related to development, and could possibly be a sticky if it leads to useful info.

Pretty broad question. First requirement, is obviously...learn java.
I'm not sure if there's any specific "HOW-TO CODE YOUR OWN CAPTIVATE ROM" threads anywhere; there's general information available on http://developer.android.com , but modifying ROM's depends on the device it was written for.
As far as porting gingerbread, it will be very difficult without source and will definitely require quite a bit of kernel work. For information specific on this, supercurio would be the one to ask. Of course, the IRC's are also a great place to get information.
By the way, welcome to XDA! And I commend your motivation to develop stuff for the community here.

http://forum.xda-developers.com/showthread.php?t=869614
Doc over in the I9000 forums has the above thread started. I look there.

geokhentix said:
Pretty broad question. First requirement, is obviously...learn java.
I'm not sure if there's any specific "HOW-TO CODE YOUR OWN CAPTIVATE ROM" threads anywhere; there's general information available on http://developer.android.com , but modifying ROM's depends on the device it was written for.
As far as porting gingerbread, it will be very difficult without source and will definitely require quite a bit of kernel work. For information specific on this, supercurio would be the one to ask. Of course, the IRC's are also a great place to get information.
By the way, welcome to XDA! And I commend your motivation to develop stuff for the community here.
Click to expand...
Click to collapse
Again, I am a developer for a living. I know Java, I'm not looking for coding tutorials. I'm looking for information specifically regarding the captivate.
As far as gingerbread, it sounds like what you are saying is that what people like supercurio are working on is not really gingerbread? More of a Frankenstein created with the sdk, mashing together 2.2 kernels and what has been released for 2.3?

lbbo2002 said:
http://forum.xda-developers.com/showthread.php?t=869614
Doc over in the I9000 forums has the above thread started. I look there.
Click to expand...
Click to collapse
Looking at that thread, it appears the roms being made are just edited versions of already compiled roms? Is samsung not required to post the full source of their roms?
I'm assuming the issue with starting with the original android source, is that we wouldn't have drivers for half of the hardware in the phone. Is the only choice then to load the already compiled drivers from the samsung builds into the rom?

epoplive said:
Again, I am a developer for a living. I know Java, I'm not looking for coding tutorials. I'm looking for information specifically regarding the captivate.
As far as gingerbread, it sounds like what you are saying is that what people like supercurio are working on is not really gingerbread? More of a Frankenstein created with the sdk, mashing together 2.2 kernels and what has been released for 2.3?
Click to expand...
Click to collapse
There are different levels of making ROMs IMO.
You can combine work from others and make your own ROM. This requires no coding experience. For instance, I took JH7_OTA, dropped in Atinms Voodoo 3 kernel, removed bloatware, added my own custom framework (icons), etc., signed it and flashed it.
Then there is the whole Kernel side of things that requires an entire development environment (Linux) and C/C++ programming skills. I'm trying to get to this point. You can start by downloading the source and building it in your own environment familiarizing yourself with the codebase.

Indeed. Packing a ROM and making the contents of the ROM are two different sides of the spectrum. Even some minor framework modifications can be performed by the most tech-inept, as long as they have a good resource to work off of.
epoplive said:
Again, I am a developer for a living. I know Java, I'm not looking for coding tutorials. I'm looking for information specifically regarding the captivate.
As far as gingerbread, it sounds like what you are saying is that what people like supercurio are working on is not really gingerbread? More of a Frankenstein created with the sdk, mashing together 2.2 kernels and what has been released for 2.3?
Click to expand...
Click to collapse
I was only prodding fun when I mentioned learning Java, just to break the ice. All I'm saying is trial and error is the best way to learn Android if you're already a decent programmer. Without knowing what the source code looked like before Samsung owned it, we don't really have a base environment to work off of, which means we are modifying work that was already modified from stock; which is why it will be pretty hard to find a lot of definitive coding information about the Captivate.
Supercurio isn't making a frankenstein 2.2-2.3 hybrid. The kernel is where all of the information about your hardware resides. Supercurio needs to take the Gingerbread kernel from the Nexus S, and modify it to run with our hardware. You can't run a 2.3 ROM without a 2.3 kernel; so we CAN'T use a 2.2 kernel to run full gingerbread; and since a 2.3 kernel doesn't exist for the Captivate, he is using the Nexus s's kernel as a base, or as a reference to merge the differences between the two, creating a kernel that will support the Nexus S ROM on a phone that isn't the Nexus S.
epoplive said:
Looking at that thread, it appears the roms being made are just edited versions of already compiled roms? Is samsung not required to post the full source of their roms?
I'm assuming the issue with starting with the original android source, is that we wouldn't have drivers for half of the hardware in the phone. Is the only choice then to load the already compiled drivers from the samsung builds into the rom?
Click to expand...
Click to collapse
Correct. We don't have the source code for Froyo yet for the Captivate(or an OTA for that matter ), a lot of ROM's being made are based off of the SGS I9000 2.2 source, and because we have that source, we have a pretty much fully functional "captivated" i9000 kernel.

geokhentix said:
Indeed. Packing a ROM and making the contents of the ROM are two different sides of the spectrum. Even some minor framework modifications can be performed by the most tech-inept, as long as they have a good resource to work off of.
I was only prodding fun when I mentioned learning Java, just to break the ice. All I'm saying is trial and error is the best way to learn Android if you're already a decent programmer. Without knowing what the source code looked like before Samsung owned it, we don't really have a base environment to work off of, which means we are modifying work that was already modified from stock; which is why it will be pretty hard to find a lot of definitive coding information about the Captivate.
Supercurio isn't making a frankenstein 2.2-2.3 hybrid. The kernel is where all of the information about your hardware resides. Supercurio needs to take the Gingerbread kernel from the Nexus S, and modify it to run with our hardware. You can't run a 2.3 ROM without a 2.3 kernel; so we CAN'T use a 2.2 kernel to run full gingerbread; and since a 2.3 kernel doesn't exist for the Captivate, he is using the Nexus s's kernel as a base, or as a reference to merge the differences between the two, creating a kernel that will support the Nexus S ROM on a phone that isn't the Nexus S.
Correct. We don't have the source code for Froyo yet for the Captivate(or an OTA for that matter ), a lot of ROM's being made are based off of the SGS I9000 2.2 source, and because we have that source, we have a pretty much fully functional "captivated" i9000 kernel.
Click to expand...
Click to collapse
Ah, thanks, that's pretty much the information I was looking for.

[Q] Can't build CM6 from sources. Help please!

Hi,
I'm trying to build cyanogenmod 6 (froyo) from sources on github for G1.
Sidenote. The reason I'm trying to do this is i'd like to modify kernel parameters. I'm trying to make the phone talk to external device using built in serial port. I can do it with my current CM6, but it looks like serial debugger engages and starts responding to the device and also steals some of the data being sent to phone.
To build I used instruction posted at cyanogen wiki "HTC Dream & Magic: Compile CyanogenMod (OS X)" which covers gingerbread but checked out froyo-stable branch at first. I know that gingerbread version stopped supporting G1 at some point last year.
Without much success even after fixing manifest to point to updated repo urls from kernel.org to googles repo etc. The problem is that apache-http seems incompatible with old sources and it is referenced by head.
I also tried froyo branch, but it doesn't build as well because something seem to be broken for dream_sapphire, and it is not present in the devices anymore.
I've tried searching for compilation errors, and general build questions/instructions here and on cyanogen's forum, but looks like CM6 is not very active these days.
Can someone point me into right direction where to search for relevant info on building it? Would getting a proper revision help or should I combine stuff from several branches to make it work?
I've already spent quite a lot of time figuring out how build is being configured and how things stitch together but without much progress on the actual build.
And with times required to sync a whole repo and build it, it is becoming frustrating.
Any help would be muchly appreciated!
Regards,
Oleg

It's dead.
I also wanted to make a cm6 rom, but I couldn't get anything to work.
I got the addresses all updated but it looks like a bunch of the files have completely dissappeared. You may be able to make it skip those, but then it may not work completely.
Go for AOSP?

Now that's a shame. I wanted to build CM because I'm familiar with it and the other thing is that they have reasonable instructions about building it. But at least I don't need to waste my time trying to figure out how to fix it.
In fact I don't need any extras they provide, a bare android would suffice to me if all the sensors and connectivity would be available. But I'm not familiar with internals of building vendor specific stuff. My understanding was that I need proprietary parts together with AOSP to build a working ROM and that's one of the things CM guys did. Correct me if I'm wrong.

aliher1911 said:
Now that's a shame. I wanted to build CM because I'm familiar with it and the other thing is that they have reasonable instructions about building it. But at least I don't need to waste my time trying to figure out how to fix it.
In fact I don't need any extras they provide, a bare android would suffice to me if all the sensors and connectivity would be available. But I'm not familiar with internals of building vendor specific stuff. My understanding was that I need proprietary parts together with AOSP to build a working ROM and that's one of the things CM guys did. Correct me if I'm wrong.
Click to expand...
Click to collapse
Nope AOSP is as easy to build now
Go to the android site and follow directions
Google for "build android"
At the part when doing repo init you need to get the right branch
Go to "build for devices" then scroll down for recommended branches and look for the dream
One thing you'll need to do differently is do "make otapackage" instead of plain "make"
And once that's done you'll need to tweak the zip and get rid of the "recovery" folder and tweak the updater-script
Oh yeah, and I don't know exactly how you would do this part, but you'll need to get the source for a newer kernel in there, like ezterry kernel and use it with 2708+ radio/spl
Unless you wanna use the AOSP kernel & spl & radio which is old
What I did is just flash his kernel after the rom, but you want to do kernel stuff so yeah...
Sent from my HTC Dream using Tapatalk

CM7 on New Bootloader - Feasible?

Hi All
I am not really a developer at all but I have had loads of experience messing around with ROMs to improve them (such as changing rils manually, using my own updater scripts, creating my own nvflash layouts and images, etc).
Recently I have been trying out CM10.1 again (mivvs ROM) on the new bootloader and also paranoid android. But both are too buggy for me and the battery life is really bad. So I am thinking to revert back to CM7 again.
I am planning to *TRY* and build my own CM7 rom from source using these fixes by Pengus (http://forum.xda-developers.com/showpost.php?p=35661482&postcount=100) to try and make it boot and run on the new bootloader. I know the advantages are very little but its just a "to see if I can" thing. It will also mean others wanting to go back to CM7 won't have to flash the old bootloader again.
I am planning just a one-time build as CM7 has pretty much reached completion.
I am posting this up to:
Make sure no-one else has already done it
Make sure one of the devs doesn't know of a reason this 100% will fail
To see if anyone else would be interested in such a ROM
To know if its possible to build from Windows (if I need Linux then so be it)
Let me know what you think

hy
I have mivvs rom and the battery life in not bad.
however, your idea is interesting .. good job!

Well, I think this is quite interesting. However, I am a big fan of PA10 and Pengus work... for me they beat GB in all aspects at the moment. However, one of the greatest pro's of having a CM7 on the new bootloader is the ability to have dual boot with CM7 + CM10.1 (or something else), since dual boot only works for roms with the same bootloader.

So far I have:
Set up Ubuntu x64 VirtualPC
Installed Android SDK and all Dependancies
Sync'd the CyanogenMod 7 Source
Sorted out the P990 Proprietary libs
Made MOST of the changes Pengus lists (although some bits are in different files)
It turns out the kernel source isn't downloaded automatically with CM7 so I need to find out how to build the kernel from source (in order to make the rest of the changes on the list Pengus made) but I think its looking good..
CM7 also doesn't have fstab.p990 but these lines can be found in init.p990.rc. Until I have the kernel source I am stuck on point 6
And I didn't mean to knock Pengus/TonyP/Mivv's work. They have helped this phone come a really long way especially now acree seems to have dropped support for it.

Just FYI
I tried this, making all the changes above, compiled the build.... but it doesn't boot.
Just gets stuck on the red lg logo.
I think the old CM kernel will not run on the new boot loader at all.
Was worth a try!

rlees85 said:
Just FYI
I tried this, making all the changes above, compiled the build.... but it doesn't boot.
Just gets stuck on the red lg logo.
I think the old CM kernel will not run on the new boot loader at all.
Was worth a try!
Click to expand...
Click to collapse
Maybe your last resort, try the excellent CM7 ETaNa kernel (link is in my signature).
But, I guess it won't work; kernels are bootloader specific.