yashsingh1/xdaforums huggingface dataset:
[Atrix 4G General] detroitjb:
VOTE

anybody who reads this, go vote on that poll. Might not to anything, but sure as hell can't hurt.
[General Questions and Answers] PieceKeepr:
I submitted this question originally through the contact email link but never got a reply.

I also belong to an archery forum owned by a buddy of mine and I am interested in finding out if the devs of the xda app would consider building a forum app for us. The xda app couldn't be set up any better as fas as I am concerned and would really like to have something similar for the archery forum. We would be willing to pay if the price is reasonable.

Thanks for any help that can be offered.
[General Questions and Answers] plainjane:
Try tapatalk instead. Same layout as xda (in fact, xda is based off Tapatalk), but supports tons of forums. It's a paid app, but you can access multiple forums. I'm not sure how to go about getting a forum added, but I would contact those devs. I believe you have to code the forum to work with Tapa, not the other way around.
[General Questions and Answers] PieceKeepr:
I'll check it out. Thanks
[General Questions and Answers] timmymarsh:
Hey thanks for the compliment re XDA app and apols you didn't get a reply.

If you have any further queries, give me a shout, cheers.
[General Questions and Answers] mdshakilahmed126:
Hi xda...I m make a custom rom for lava iris x1 marshmallow version.. No any bug...original marshmallow version.. feel original marshmallow....
[Epic 4G General] Top Nurse:
Since we are all wondering what is responsible for this rash of bricks I thought I would start a topic about it. I'm hoping some of our electrical engineering crowd will pipe in on this.

First of all I'm not an engineer and all my knowledge of electronics comes from the practical and theory side of being an amateur radio licensee and a tinkerer of electronic devices.

I think that undervolting is just plain crazy. Our phones are devised to perform in a certain manner at a specific range of voltages. Circuits that are under volted tend to destabilize and do strange things. Resistors change the circuit and the wrong input voltage can change eveything downwind so to speak. Capacitors that are undervolted may not even fire at all. With the advent of LSI's a component may get smoked and you won't even get the satisfaction of smelling the magic smoke (acrid burned smell) ;)

Now over volting definitely has much more applicability here because it's just a plain fact that juicing the cpu results in higher clock speed. Problem here is how to dissipate the heat generated. If we were talking about a desktop we could put on a big heatsink and fan and get decent results. If we wanted to go faster we could do liquid cooling and direct freon injection (phase change) on cpu if we really want to have some fun (if anyone is interested in a world record Epic OC attempt on liquid nitrogen send me a PM). However, none of these methods is going to work well on a phone if you want to keep using it to make phone calls. ;)

From my perspective we can easily OC any processor 10-15% without worrying about heat problems and no under/over volting needed for most phones. As mentioned in another thread, to paraprase Duracell, some can take a licking and some will quit ticking. However, outside of this narrow range we are literally asking for odd kinds of trouble. Just like what we have seen of late...

Sent from Bonsai 7.0.3
[Epic 4G General] gTen:
Well there is nothing wrong with undervolting..we just need to take things a step at a time...instead of undervolting everything doing 1 change at a time would be much more ideal as its easier to root out problems. One thing I notice is lately these things are released in form of 10-20 changes to try to get better then the kernel before it..instead I would rather see isolated test kernels of 1 thing at a time...so lets say UV ram was the culprit(not saying it is)...but maybe LCD UV is ok..and thats probably what most of us wanted

In my case I was running Genocide and was getting really good underclocks(better then most people) and things were stable..when I saw LCD underclocking on the Vision I just couldn't resist...even though I noticed problems from the get go and my intuition was telling me to go back to Genocide as I had better undervolts there anyways the greed of having LCD undervolt was too much to give up.

What ultimately got me was when I saw the thread about the issue in the kernel...I paniced as I have been having issues and proceeded to shut down my phone to get back into clockworkmod...if I didnt do that my phone would probably still be alive...

So ironically what bricked my phone was not only the kernel itself but the warning about the possible brick lol...thats why I quickly put up the warning to others not to panic and shut down their phones following my footsteps...I dont blame anyone but myself..

There will always be sacrifices along the way..thats just how development is...
[Epic 4G General] ecooce:
I agree,I think we are going down the wrong road when it comes to kernels,but everything is trial and error,just wish more time was spent testing; Not just "hey it boots,testers like it" 2 hours later its uploaded...
[Epic 4G General] gTen:
Well as I said it would have been nice if we got the kernel features separated...aka 1 kernel with UV ram, one kernel with UV CPU and one kernel with UV LCD..then 10 days later if there were no issues go to UV CPU + LCD kernel and UV RAM + UV LCD Kernel..and then if everything is ok 10 days later merge them all into one..

My regret is not bricking my phone but the fact that it was bricked without providing much use...at the very least if my phone was bricked during a UV ram only test for example we would know where the issue was and not go that road..instead we are now stuck guessing the possibilities...

I guess our ambition is getting the better of us :/..slow and steady wins the race...
[Epic 4G General] Top Nurse:
I totally agree with you about all the changes at one time being detrimental to good development. I've brought this up several times with the Bonsai Team. The problem from my perspective is that if you change 20 things and you have a problem you have no clue about what screwed what. Making one change and making observations is the hallmark of scientific testing. Now sometimes doctors use the shotgun approach, but only when they don't know what will work and someones life is on the line.

Sent from Bonsai 7.0.3
[Epic 4G General] epic4GEE:
Yeah I agree as well, however these are regular guys and gals that do this in their own free time and if they compile one thing at a time I believe it becomes way more time consuming. It could literally take months or even years to completely shake down a build, going one by one. Bleeding edge is the only way it can really be done in an open source/freelance environment like this.
[Epic 4G General] gTen:
your not compiling line by line...your just compiling 1 feature at a time...it may take more time to compile, but you also end up saving time on debugging.

I mean its up to the devs to do their own thing, we can't exactly tell them what to do..but we can offer our suggestions..its up to them if they wish to try it that way or not.

And bleeding edge is not how its done in an open source environment..in an open source environment a feature is tested 1 at a time by forking the tree..then when its been properly finished and tested it gets merged back into the main tree for a release. If it fails to hit stable by time of main release it rolls over to the next release.

Of course everyone has different development policies but the above is a very common one.
[Epic 4G General] KennyG123:
Definitely agree about being real careful with undervolting just to squeeze a few percent out of the battery life. Top Nurse for not-an-engineer you are essentially correct about disrupting circuits especially transistors and diodes that function on a specified voltage drop. I, myself, thought I bricked twice only to find out I had undervolted my sleep speed of 200 Mhz by 125 mV essentially bringing it to 100Mhz. The interesting thing is Genocide has all this undervolting and 1.4Ghz speeds and yet I have not heard of any rash of bricks there. Maybe that kernel should be used as a comparison baseline.

Do you BONSAI?
[Epic 4G General] ecooce:
If I remeber right Genocide dosnt UV the RAM...
[Epic 4G General] mattallica76:
Does it undervolt the display?
[Epic 4G General] gTen:
no it doesnt, but i dont think display is the issue..also genocide doesnt have BFQ..only CFQ
[Epic 4G General] MysteryEmotionz:
No vision kernel was the first kernel publicly released that uv the screen and ram
[Epic 4G General] mattallica76:
I do believe the bonsai beta 4.1.0b9 kernel had the display undervolted as well, and I believe the BFQ was enabled by default...someone correct me if I'm wrong. More commonalities I'm sure.
[Epic 4G General] gTen:
I found this changelog for bonsai:

- Voodoo color

- Undervolting in several modes including Screen and RAM at certain cpu frequencies

- Overclocking and underclocking configuration for 100mhz-1120mhz is now standard

- Read_ahead tuning to 4096 bytes

- Volume switch provides silent and vibrate control

- Upgrade to CWM 3.0.2.4

- Reduced battery % limit to 5% for Camera, VideoPlayer, and MusicPlayer.

- Increased windowsmgr refresh events_per_sec from 60 to 68

- Updated Maps.apk

---

I dont see BFQ..unless they always had it...

One thing I do notice with Genocide vs VisionKernel is on Genocide kernel 100mhz never really worked...and i odnt mean crashing...I used CPU Spy and it never showed 100mhz..on VisionKernel I did have it hit 100mhz a few times..

Edit: I see BFQ was added on the 31st - r458 - Add BFQ scheduler from Paolo Valente
[Epic 4G General] mattallica76:
On the stock Bonsai 4.0.1 kernel, it would not scale down to 100mhz with the conservative governor, but it would with interactive. The 4.1.0 b9 kernel fixed the issue and it would scale to 100mhz with no problem. (other than bricking your phone)
[Epic 4G General] gTen:
Hmm..does any other kernel achieve 100mhz?

When I was looking at CPU Spy usually at max it would be like a few seconds on the 100mhz frequency...I would think when shutting down a phone 100mhz frequency might be used during a short interval..the only other person who claimed he got same thing and not on power down but at lock screen..which I know after waking it hits 100mhz...there might be a pattern here :/
[Epic 4G General] KennyG123:
So there are a lot of similiarities between the 2 bricking kernels and differences to genocide. Since there is no charging light when plugged in, it is still some catastrophic failure. Would RAM or video failure be enough to prevent the phone from charging? Or turn on the charge light?

Do you BONSAI?
[Epic 4G General] gTen:
I find it very very very very unlikely that the screen would do this..usually the screen is a separate component..In a pc for example ive had pc not turn on due to bad ram though...
[Epic 4G General] KennyG123:
Wasn't thinking the screen, I was thinking the video components on the circuit board due to LCD undervolting. But was def thinking dead RAM as a possibility.

Do you BONSAI?
[Epic 4G General] stir fry a lot:
With just Voltage Control my phone would hit 100 every blue moon. In conjunction with SetCPU on conservative it now idles fine at 100mhz and UV'd by 125. It seems to automatically revert to noop whenever I set it to bpq.
[Epic 4G General] ecooce:
Well Vision 1.1 scales to 100mhz perfectly,using setcpu ondemand... I'm still gonna say the culprit is the RAM UVing,I know I've said it before,and I don't think 100mhz has anything to do with bricking.
[Epic 4G General] gTen:
You checked this on cpu spy?

And I am not doubting you..but we have to consider ALL possibilities and similarities..since a person seems to have bricked while not having a 100mhz step thats most likely not the case.

sometimes it can be a combo of things..so far out of all I gathered based on peoples testimonies either the UV ram or the BFQ is the culprit..

Right now I am not trying to do anything technical to figure it out..just narrow it down via process of elimination.
[Epic 4G General] ecooce:
If your wondering why deep sleep is so low,its because I use my phone as a music player also...

And thats Vision 1.1 not 1.0,lol
[Epic 4G General] llamaunix:
I suspect it wasn't the LCD uv, but maybe the RAM uv instead. I was actively using my phone when I started noticing the corruption and force closes. LCD was perfect, after I rebooted LCD was still fine but entire FS was trashed, couldn't even get back into CWR.

Some facts:

Stock EC05 with just Vision 1.2 kernel

CPU UV about -75mV

No overclocking, no 1 GHz step either

Set using Voltage Control

RFS file system and default CFQ scheduler
[Epic 4G General] insanity213:
Correct, the only undervolting in Genocide is the CPU itself.

Just my opinion, but undervolting RAM is a bad idea. Undervolting the CPU just a little bit isn't horrible, but the OP couldn't be more correct. You start dropping voltages too low in even the most basic electrical circuits and you're likely to get all kinds of weirdness. In a device as complex as the Epic theres even more that can go wrong.

Running Genocide kernel here between 200 and 1200 mhz with 25mv undervolts on all steps except 1200. The phone has been rock solid. I may have gained a small percentage of battery life but I really haven't tested much. I wouldn't drop the CPU any more and would never consider undervolting the RAM. Drop the voltage of the RAM in your PC and see how many oddball errors and blue screens you get.

Also, I don't know how good the quality of the voltage regulator in this thing is, but undervolting will make the regulator work overtime trying to keep everything running. Remember, wattage is the true measure of power, not voltage. I suspect the regulator is designed to drive up the current a hair when running undervolted to deliver the proper amount of power. If the same regulator is used for the proc, RAM and screen you're really beating the hell out of it and it will likely fail which is probably what's happening here. If it pukes hard and the current spikes up too high RAM is the 1st thing that will pop.

Just my .02...
[Epic 4G General] gTen:
There are 2 power managements in the phone:

Maxim MAX8998 Power Management IC

and

Maxim MAX8893C Power Management IC

By the sound of it MAX8998 handles the CPU..
[Epic 4G General] Top Nurse:
I *think* the one we were trying to get spec sheets on is the 8998 chip IIRC. That was where we hit a dead end as Maxim acts like they never made it and Samsung isn't too interested in giving out info to a bunch of hackers. :/

Sent from Bonsai 7.0.3
[Epic 4G General] gTen:
From what Ive been reading 8998 looks like a custom design for samsung hummingbird processor only..
[Epic 4G General] Top Nurse:
Correct, and that is why the Bonsai Team is stuck at the moment. We need to know what it does, pin outs, and programming because that is where our trail of bread crumbs led us.

Anyone got an in with the electrical engineering departments at Samsung or Maxim?

Sent from Bonsai 7.0.3
[Epic 4G General] Top Nurse:
I guess my brain cells are not heading towards early alzheimers. Amazing what the brain can store and fire back when needed. :D

So who around here has access to a frequency counter, occilloscope, and other electronic wizardy? Just thinking here about what is really going on with our phones when we undervolt them. Are we setting up secondry occilations that might cause a catastrophic failure?

A lot of people sometimes forget that while the Epic 4G is a fancy computer that we are modifying the hell out of, its primary purpose is a RF device. IIRC, cell phones fall under Part 15 of FCC rules. This makes them vulnerable to a lot of problems that it must accept to be FCC approved. Thus some kinds of things aren't designed into the hardware to reject.

Think we need some comments here from any RF engineers hanging around that would know what odd RF problems we could be generating with under volting ram and cpu.

Sent from Bonsai 7.0.3
[Epic 4G General] ecooce:
If my stepdad was still with us he would hop right on this,he used to build boards,install alarms,mechanic,jack of alll trades really,he had the occilloscope,nice volt meter,everything,just I don't know how to use them 100%,voltage meter that's about it.
[Epic 4G General] Krazy_P@:
I use genocide, I flashed the set 100mhz on boot and I spend probaly 40% of the time.... and can get stable middle of the road uv's but vision 1.2 crashed my phone tuff w/o overclocks and only -25mv uv on all stock frequences but none @600. After that I went back 2 genocide, glad a lil I did... sorry 2 har about all the bricks, idk but this sounds like a case of all the parts sum being greater then the whole. Maybe just 2 much uv'ed @ the same time...
[Epic 4G General] Top Nurse:
I edited a post instead of making another post. Seems some got in before I could mod my thread. Stupid..because now I'm posting about my previous post. ;)

Sent from Bonsai 7.0.3
[Epic 4G General] tmspyder:
Not a professional by any means but I do love to OC my desktop, and in my experience

undervolting a cpu or fsb has never been a problem. To far out of range and the system just shuts down. reboot to bios and fix it. ( not quite so simple with a phone I know)

However suppling the memory controller with less or more than the range listed on my ram has always led to more serious problems. I have at least 6 sticks of high end ram that is useless in a box in my closet from doing just that.

I have refrained from messing with anything more than the timings on ram for quite some time now.

As for under volting a display controller... I'm pretty sure thats gonna end badly as well.

Edit: A Vapor cooled speed record attempt intrigues me :) ... As long as its not my equipment we are talking about here lol;)
[Epic 4G General] KennyG123:
Undervolting certain circuits is bad mmmmmkay.
[Epic 4G General] G.I.Geoff:
Okay, thats new, and I wonder why we weren't told earlier....And have these (fatal) issues affected the "Twilight" Kernel? OR ACS's SyndicateFROZEN ROM? (As this is what I am currently running)
[Epic 4G General] gTen:
No, this is ONLY for visionkernel 1.2 and bonsai 4.1 I guess :/
[Epic 4G General] Top Nurse:
Not sure about the vision kernel, but from the Bonsai side we think that we will be making some changes today in our beta code for 4.1.0. I think these ideas of under volting ram, screen, and cpu came from the changes in the Galaxy Tab. However, it appears that the chip in the Tab is configured way differently than our Epic (sorry, but not at liberty to discuss where we got this info from) and that is why we are seeing a sudden uptick in bricks.

As I have stated before, under volting is an extremely bad idea given the minimal gains realized. Another fork gone bad, but it allows us to concentrate on other more interesting capabilities in the code. :D

Sent from Bonsai 7.0.3
[Epic 4G General] Bluerai:
I've got a few friends that have access to anything and everything EE related at my University ;)
[Epic 4G General] gTen:
Can you/they get the datasheet on: Maxim MAX8998 Power Management IC ?
[Epic 4G General] ecooce:
EE = electronic equipment if I'm not mistaken...
[Epic 4G General] gTen:
Bah....I didnt read the quote he was responding to..didnt display properly..I was thinking a university could request the datasheet and have more likely chance of a response.

Though EE usually means Electric Engineering...
[Epic 4G General] ecooce:
LoL,yeah that too... :)
[Epic 4G General] Custodian:
I agree with all you folks here. I haven't had a problem with vision 1.2 yet.

My specs:

*Tweaked Voltage Control

100 uv -200

200 uv -200

400 uv -150

600 uv -75

Auto Memory Killer settings:

200

225

250

troll stomping beast
[Epic 4G General] dwyw42:
What do you need the datasheet for?
[Epic 4G General] gTen:
I just said it...Maxim MAX8998 Power Management IC
[Epic 4G General] dwyw42:
I meant why do the rom devs need the datasheet
[Epic 4G General] dwallersv:
what you say above is nonsense.

Power supplies cannot force both voltage and current in a load to independent values. Only one or the other can be controlled, the other being a function of the load impedance.

A load may not be linear (like a simple resistor is - active loads usually are not), however it is the load that will determine the current draw for a given voltage presented to it.

Want to push more current through the load? How do you make that happen? Think about it: The only thing you can do to effect that is to change the voltage (for a typical passive load, you increase the voltage).

Any load is going to draw what it's going to draw at a given voltage -- there's no way for a supply to push more current through a load than it draws on it's own at any voltage level. So, your theory above about what voltage regulators are doing to maintain certain power levels is simply untrue, and frankly, impossible.

Sent from my mind using telepathitalk
[Epic 4G General] dwallersv:
I'm an engineer, and in the distant past in my career have designed complete computing systems from the ground up (although those were the days before SOCs -- we were designing HP1000 minicomputer systems).

Our phones are nothing special in this regard. They are pretty typical computer systems architectures, with a rich set of peripheral devices, integrated into the bus architecture and accessed in long-standard ways.

The things we're messing with here in terms of clock and voltage control are, for practical purposes, no different than the same capabilities and manipulations on a regular old PC with a tunable motherboard. The risks and implications are the same as well. The problems people are experiencing also mirror what PC overclockers run into too.

Messing with DRAM voltages is always very dicey, and generally a bad idea. DRAM essentially "leaks" charge on each transistor storing a bit, so must be refreshed regularly to pump that charge back up to maintain the bit value. The memory controller handles this automatically. The rate of refresh is usually configurable.

That rate interplays closely with voltage levels. Reducing voltage will reduce the time to data loss on a cell, requiring more frequent refresh to ensure data integrity. DRAM designers spec all of this for optimum operation, as well as allowable ranges. Playing around with DRAM voltages by experiment without also addressing refresh characteristics according too design specs and recommendations incurs a very high risk of exactly what we're seeing... A system that seems to work fine, but depending on the variations in tolerance from device to device, and corner cases in usage patterns, some people will wind up with data being corrupted.

Sent from my mind using telepathitalk
[Epic 4G General] dwallersv:
FWIW, I have a Protek 840 (osc, counter, multimeter, and a lot more).

I'd be more than happy to examine and investigate someone else's brick -- I'm not rich enough to risk my phone.

Sent from my mind using telepathitalk
[Epic 4G General] Entropy512:
More like kernel devs. The MAX8998 controls nearly everything power-related in Samsung phones. It controls battery charge current, charge termination, CPU core voltage, and many other things.

(FYI, I came here via a search for MAX8998... I'm trying to tweak the charging algorithms of the AT&T Infuse without doing anything harmful to the battery - having the datasheet for this chip to explain what some of the register flags are supposed to do such as ESAFEOUT1/2 would be VERY useful.)

Has anyone had success finding a MAX8998 datasheet? Normally Maxim is very good about providing datasheets for parts, but the 8998 seems custom for Samsung and quite proprietary. :(
[Epic 4G General] mattallica76:
To my knowledge, we didn't have any luck getting our hands on it either.