P1000/P1010 Charging current? - Galaxy Tab General

The stock charger says 2000mA on it. I built a circuit using a 5V 3A switching regulator to plug into my car. But when I plug it in, the tab displays the x over the battery icon indicating insufficient current. It does seem to be trickle charging but what am I missing to get the tab to enter charge mode?

I should add that the voltage is indeed 5v so its not a droop issue and while connected to my circuit, the tab is in usb debugging mode. Any thoughts? Is there a hardware specific forum I should be posting this in?

You need to signal to the device that it can pull more than 500mA. Afaik it should work something like this: http://blog.curioussystem.com/2010/08/the-dirty-truth-about-usb-device-charging/ Don`t exactly remember though whether Samsung uses exactly that setup or a slightly different one - but i think i also read something here about those 200 Ohm resistors.

Related

[Tut] Make car charger behave as "charger" instead of "computer"

As probably several other users, I have set my hd2 to NOT charge when connected to pc, as I often plug the cable to transfer pictures, cabs and the likes. This is useful when I actually plug it to the PC, and it regularly charges with stock/compatible cable if connected to mains charger.
Problems could arise when you connect the microusb cable to the standard carlighter plug with an adapter having a female USB connector in it. It gets recognized as a "pc" and thus the device won't charge unless you re-enable charging when connected to PC.
In case you experience this, as per link found in second post of this thread, you can short the two middle contacts of the USB connector (the data pins) so the phone recognizes the charger as a proper one instead of mistaking it for a PC.
http://www.pocketpc.ch/htc-hd2-sons...en-hoehere-ladestroeme-akku-laed-im-auto.html
desribes modification of car charger, sorry but it´s german. HD2 detects via USB data pins, if it´s connected to PC or charger. If USB data pins are connected like described in above, it will be charged by the car adapter as well. To achive this you´ve to modify your adapter as described.
Regards
Georg
Thank you! Google translate is helping me... and believe me or not, it seems that what I was guessing is actually true: you need to short the data pins of the usb cable... could you confirm please kleiner_onkel? I am not quite so sure of what I am reading with google, as that kind of english is quite far-fetched
n that case I could also avoid messing with the insides of the usb-lighter adapter, and just short the cables inside an external USB hub
EDIT: I just tested it, syhorted the middle data pins of the usb-a plug inside a cheapo usb1 hub, it works and charges the phone when "charge from pc" is disabled.
Will meddle to clean the job and then will update first post
Can you please, for the sake of the slow minded such as I, explain why you would not want to charge from PC/USB?
pa49 said:
Can you please, for the sake of the slow minded such as I, explain why you would not want to charge from PC/USB?
Click to expand...
Click to collapse
+1 for why not.never understood why it would even be an option.I could understand if we still used nickel batteries, but not with li+
Shorting the data pins also tells a device that it can use up to 1.85A of current (versus the 500mA of USB2). Your car charger will have circuitry (of varying complexity, depending on the model) to drop the 12V from the car to something usable by your phone (5V). If the components in your charger can't handle the 1.85A current, you could land up with a pretty hefty repair bill. Be careful out there....
Edit: Need a worst case scenario to see how bad it could be? In the most basic case there'll just be a resistor in the car charger. That resistor is likely 1/4 watt, 1/2 watt tops. Put 1.85A through it and it can pop, potentially going closed (short) circuit leaving your phone with 12V to deal with. The extra current that comes with that means you fry part of your charging circuit at best, your battery (possibly explosively) somewhere in the middle and the entire phone at worst.
samsamuel said:
+1 for why not.never understood why it would even be an option.
Click to expand...
Click to collapse
I do see a use, if you're on a laptop running on batteries, you don't necessarily want to empty your laptop batteries faster by recharging the phone if you don't need to. But that's the only one.
Aterlatus said:
Shorting the data pins also tells a device that it can use up to 1.85A of current (versus the 500mA of USB2).
Click to expand...
Click to collapse
More like 0.85 actually, like what it draws from the original charger.
Aterlatus said:
In the most basic case there'll just be a resistor in the car charger.
Click to expand...
Click to collapse
Then that car charger would NOT work and would fry every device connected to it...
Car chargers have voltage regulators, which have overcurrent and overheat protection, linear ones for older ones, DC/DC switching ones for everything you find today.
I believe there's actually still an extra step from this mod to the phone knowing it is on the original charger. I have both a Chinese USB charger and a car charger, rated at 650mA and 800mA respectively. On both (with soldered pins), the HD2 will charge at 600mA, not 800-900 like with the original charger. But 600 is of course already better than 450.
kilrah said:
More like 0.85 actually, like what it draws from the original charger.
Then that car charger would NOT work and would fry every device connected to it...
Car chargers have voltage regulators, which have overcurrent and overheat protection, linear ones for older ones, DC/DC switching ones for everything you find today.
Click to expand...
Click to collapse
From: ht tp://pinouts.ru/Slots/USB_pinout.shtml
Dedicated charger mode:
A simple USB charger should short the 2 data lines together. The device will then not attempt to transmit or receive data, but can draw up to 1.8A, if the supply can provide it.
Click to expand...
Click to collapse
It's in the spec, and a car battery won't have any problem supplying the current. A cheap (read: chinese off ebay) charger might well employ just a simple resistor. Sure, any decent charger will use a voltage regulator or a buck converter to maintain the correct voltage. That doesn't mean that ALL will, hence the warning to take care.
"If the supply can provide it" is the key. The USB device will see if the supply can't give that much and its voltage starts to drop.
And anyway the HD2 would never draw 1.8A or it would damage its battery.
I noticed much the same thing by accident as reported in this thread
http://forum.xda-developers.com/showthread.php?t=638007
Beware that if your HD2 is set up to detect it, it will turn on Navipanel when plugging in this type of cable
pa49 said:
Can you please, for the sake of the slow minded such as I, explain why you would not want to charge from PC/USB?
Click to expand...
Click to collapse
samsamuel said:
+1 for why not.never understood why it would even be an option.I could understand if we still used nickel batteries, but not with li+
Click to expand...
Click to collapse
I may be the slow minded here. BUT
1) Everyone having had even third-person experience with laptops knows that using one with a battery inserted and "most of the time" attached to the external power unit, makes the battery die pretty soon, and all laptop batteries are Li-Ion based since quite a while; sure, part of that damage comes from the heat generated on the battery both from the charging and the laptop being turned on, but all the rest is caused by the "unnecessary" repeated charges (confront the "battery university" website for this)
2) I often plug/unplug the cable from the pc to move several small files, I just don't feel comfortable doing it if everytime the battery gets a "charging hit", for the aforementioned reasons
3) I want to be able to charge the device when I choose to and not just everytime I plug it somewhere
4) enabling the car charger as "proper charger" lets the device take up more current and charging faster
5) I've always behaved, with all my Li-Ion powered devices, in a way that I would charge the battery when it got to ~20-30% and not before, reducing the number of times I actually charged it; the definition of "recharge cycle" is not the easiest one here, and "battery university" has an interesting one; but since my behaviour until now has given its good results, I'll just keep doing that
Aterlatus said:
Shorting the data pins also tells a device that it can use up to 1.85A of current (versus the 500mA of USB2). Your car charger will have circuitry (of varying complexity, depending on the model) to drop the 12V from the car to something usable by your phone (5V). If the components in your charger can't handle the 1.85A current, you could land up with a pretty hefty repair bill. Be careful out there....
Edit: Need a worst case scenario to see how bad it could be? In the most basic case there'll just be a resistor in the car charger. That resistor is likely 1/4 watt, 1/2 watt tops. Put 1.85A through it and it can pop, potentially going closed (short) circuit leaving your phone with 12V to deal with. The extra current that comes with that means you fry part of your charging circuit at best, your battery (possibly explosively) somewhere in the middle and the entire phone at worst.
Click to expand...
Click to collapse
As kilrah stated, 1.85A may be the max specification, yet the HD2 is NOT going to get that much from a recognized charger. The german thread pointed from the second post of the thread is also specific about it, the intook currents are higher, but not that higher... plus I've peeked inside the car lighter charger, and it's got no single resistor Also, the max 2A is useful when you plug several other things to it for charging purposes other than the HD2, and that's why I connect the HD2 to a USB1 hub connected to the carlighter charger
For a briefly useful reference, my iPaq 214 only took max 200mA from the miniusb plug no matter the charger capacity not the charger "nature", so devices do have a regulator, and it would be reasonable to think that a multihundred euros phone has one, and pretty efficient at it
So aside from hacking the USB cable, is there any other way to make the car usb charger act like a car charger? Or I should save my time and just buy an actual car charger, instead of a universal usb one....?
Thanks!
atagent said:
So aside from hacking the USB cable, is there any other way to make the car usb charger act like a car charger? Or I should save my time and just buy an actual car charger, instead of a universal usb one....?
Thanks!
Click to expand...
Click to collapse
solder together the central pins on the charger output port, it's the exact same principle
Even thought hacking a cable is "safer", as you're playing with a ~2USB asset instead of a ~5USD one, and you have to connect a usb cable to the car charger anyway in order to charge the phone

Faster USB charging?

Just got a new motheboard which has high output USB charging for iPhones, pads etc.
Can this work on N1 ?
http://gigabyte.com/MicroSite/185/on-off-charge.htm
edit: driver link is at the bottom for all the hackers. Hopefully its just changing string from apple to android hehe
kazprotos said:
Just got a new motheboard which has high output USB charging for iPhones, pads etc.
Can this work on N1 ?
http://gigabyte.com/MicroSite/185/on-off-charge.htm
edit: driver link is at the bottom for all the hackers. Hopefully its just changing string from apple to android hehe
Click to expand...
Click to collapse
Hopefully not, I dont want my nexus one to be iphone.
But as you know nexus one is using qualcomm motherboard.
But aslong cyanogen and fm transmitter is working there is no problem wiith your phone.
Dear lord what a crappy reply. Stick to disney mate.
It should, it basically just converts the USB port from .5 amps to 1 amp, like a wall charger.
elkyur said:
Hopefully not, I dont want my nexus one to be iphone.
But as you know nexus one is using qualcomm motherboard.
But aslong cyanogen and fm transmitter is working there is no problem wiith your phone.
Click to expand...
Click to collapse
WTF??? May want to lay off the halucinogenics
elkyur said:
Hopefully not, I dont want my nexus one to be iphone.
But as you know nexus one is using qualcomm motherboard.
But aslong cyanogen and fm transmitter is working there is no problem wiith your phone.
Click to expand...
Click to collapse
lol I seriously hope this is a joke!
I agree with JCopernicus, it should definitely work.
I installed the software in the first post but it still charges very slow compared to wall outlet
Slightly OT, but I've got a USB adapter that plugs into the wall that came with my iphone and when I plug the N1 USB cable into this to charge the N1, it still charges very slowly compared to using the proper wall adapter, why is this? Does this iphone adapter restrict the voltage or something?
Generally, "charger detected" is a circuit that has USB data pins shorted together. So when the phone's USB device probes the lines and detects them shorted, it knows it's connected to a power supply.
But since USB max current spec is 500mA, the current draw is restricted - either by the phone or by the supply.
There might be some other connectivity trick that allows the phone to know it can draw x2 current from the socket and won't damage anything. Most phones probably don't limit the current draw and count on the board to do it. Some boards don't limit the current output, or limit it higher. And the fast chargers provide pulsing voltage - which isn't like USB.
So for the board to be able to charge the device, it needs to detect a device that can use pulsing voltage, and enable such voltage on the socket. It doesn't detect Nexus as such a device, I believe, and that's why the charging is slow.
Faster charging with USB
Building on Jack_R1's response, I believe that the phone is limiting the charge rate. You can make the phone "realize" it is connected to a charger rather than a data connection by shorting the 2 middle USB pins together. I have done this in several car chargers, and the N1 About/Status shows charging (AC), which is the faster charge mode. While you can short the pins in the larger end of a dedicated USB cable, if you can disassemble the connector, I found it much easier to open the charger itself to short the pins.
i also have a gigabyte mobo that has this feature but i havent gotten around to test it out yet. I dont think it would work because the feature is software based and will only bump up the voltage if the program detects an iphone connecting to your computer. Gigabyte doesnt want to be liable if they bump up voltage on every device you plug in and fry something.
btw I have tried charging my n1 from my computer and its extremely slow. started charging at around 5pm on sunday and at 11pm it went from about 23%-97% lol.
Yes, USB charging is very slow. It's actually good for the battery, though.
Maybe someone with some know how can look at the driver files for this 3x tech and see how it checks if its an Apple device. Then fool the check and presto!
Shame I don't know how to do any of this
There is a simple hardware (don't worry, it's on the cable) mod for faster charging; however, make sure the phone has good air vent (it means NO CASE when charging).
1. modify your microUSB cable, disconnect the data connector the A (host) plug, then shorten the data connector to the B plug. (This can charge N900 properly, and speed up n1 charging).
2. modify your powered (with AC adapter plugged) USB hub. Simply shorten the #2 and 3 connectors on USB jack. Make sure you cut the copper strip going to the chip or malfunction may occur.
These modification can greatly speed up the charging, but phone will produce a lot of heat (that's why you must have the phone "naked").
I don't understand this. If the phone + battery are capable of being charged at 1000 mAh from the wall charger then why need extra cooling when asking for 1000 mAh from a PC USB socket?
Mine's still defo getting only 500 mAh from the PC USB despite it being able to give up to 2700 mAh for iPad!!! All I want is my 100 mAh charge.
Because what he suggests isn't a proper charging but rather removal of slot power control, and will damage the battery / phone, if succeeds.
Proper charging at 1000mAh requires pulsing voltage - his hack doesn't provide that. Your MB does, but it requires SW intervention to turn it on.
So can someone brew the intervention ?
martinl1030 said:
i also have a gigabyte mobo that has this feature but i havent gotten around to test it out yet. I dont think it would work because the feature is software based and will only bump up the voltage if the program detects an iphone connecting to your computer. Gigabyte doesnt want to be liable if they bump up voltage on every device you plug in and fry something.
btw I have tried charging my n1 from my computer and its extremely slow. started charging at around 5pm on sunday and at 11pm it went from about 23%-97% lol.
Click to expand...
Click to collapse
They are not doing anything to the voltage, simply allowing more current to pass.
And as said in this thread, any typical data USB cable will charge very slowly. And most standard USB ports charge well less than the max specced 500mAh, in fact my subnote at work I found charged my old phone at around 150mah one time when I was dead and needed to top off and it's all I had available.
i'm not sure of the pinout on the micro USB port but i'm pretty sure that that the Mini USB-B port that was used on phones like the G1 used shorting the -Data pin to the unused 5th pin (actually pin 4 on the connector pinout) to activate AC charge mode. some devices actually require a resister of a certain value to be placed across them to work(i know older motorola phones did like IDEN's)
one thing people often forget but should not forget is that current is drawn from the device using power. its not forced on the device. voltage is forced on a device and while a variance is usually ok for devices depending on how they were designed generally its not a good idea to exceed +1.5v on any low power DC device. 120V AC devices are designed to actually work in a much wider range like 100-130V but thats because of the power supply/nature of AC power. it always varies and in japan they use 100v 60hz AC so many electronics power supplies are designed to work in the full range to save costs and only have to make 1 unit for all (same deal with 220-240 switches on PC power supplies)
the reason why you don't want to do this mod is you could damage you PC's motherboard by pulling too much current from its circuits. USB spec is 500ma. performing this type of mod on a power adapter (car or AC) that does not get recognized as an AC charger by the phone is a safer way to go. worst case senario is you break the charger (unless you mess up on the pinout then you could damage you phone too though)

Battery charge current help needed

Long story, but I bought a used Fascinate without the stock charger.
Could someone install, or hopefully already have, the "Battery monitor Widget". Then plug their Fascinate into the stock AC charger or stock car charger (NOT the USB on a PC), and let me know what the usage (ma) reading is on the widget.
More of the story. Basically, I know that at least on older HTC devices they would pull more charge/operating power from a non-USB connection. Actual USB is limited to 500ma load, so they had a system that kept the current low on USB and bumped it up for non-USB. All of the non-stock cables that I have show a very low charge rate on the Fascinate. It in fact runs the battery dead while on charge and I use the phone with GPS software.
i can tell you the factory charger is putting out 5v at .7a(700ma).
Mylt1 said:
i can tell you the factory charger is putting out 5v at .7a(700ma).
Click to expand...
Click to collapse
Thanks, it is good to know that they stick with 5V. But it just means that it can put out up to 700ma. I suspect it is using about half of that.
If you can cut open the wires and insert and ammeter in series, that is what I need to know.
edit: nvm ...
Found it. I have been searching for this for a couple of weeks and just now stumbled on the right search keywords.
For anyone that wants to know.
The Fascinate appears to pull about 350ma from the 5 volt supply normally. But, if you short out the USB D+ and D- lines in the charge connector, the charge current goes up to about 600ma.
That will help me not have a dead battery when using the GPS.
Oh, as an added bonus, you don't get the USB / Debug notification.

Thinkpad tablet slow charge analyzed

I have TPT for 10 days now.
I have usual iisue with USB charging. When used like standard smartphone = put it to charger overnight. Not usable anyway. Charge rate about 5% per hour, which means 20 hours per full charge???
I even consulted it with local technical support. I was adviced to buy docking station with external power adapter .....
So ... I took regulated power supply, made a USB socket connected to it and started to measure
.. and look what I found
When device is switched on, usb power oscilates sligthly under 1000 mA. It is NOT using all available power of 2 Amps of stock power adapter!!!!!
But ... when I power the device off using power button. The current goes down to 300mA for about 5seconds and then raises to full 2 A!
Conclusion? It seems like control issue of the charging ciurcits. What if we can enable full 2A power even when turned on? SW issue?
Is there any chance, how to instruct internal power circuity to use all available power? ADB?
Well I guess that explains the slow charging that people have been reporting. I picked up a dock for my tablet from amazon for about $30 shipped. Now I just put my USB charger in my bag for when I am out and about and dock it when I get home. That being said when I was charging via USB before I had the dock, a full charge seemed to take about 6 hours or so.
As for your question regarding modifying the input charging rate while powered on, I am not sure that can be done via ADB. I am taking a stab in the dark here, but I wouldn't be surprised if the charging rate was hard coded into the power circuit. Which would make some sense so as not to draw to much power if someone wanted to try and charge their tablet while having it plugged into a laptop or USB hub. I am not sure if it has an auto sense capability to determine whether or not it is charging via USB from a port or from the power adapter. I do know when I hook it up to my computer to transfer files it offers me the option to charge via USB, but I think that is a software thing and not hardware. I could be wrong. Maybe if we had access to the board schematics I could figure out. I can read schematics and might be able to figure it out.
Any chance you could get a proper reading via the docking port on the tablet? I would be curious to see if it is always at 2A. I haven't counted the pins but I don't see why you would need more than VCC+, VCC-, GND and maybe a sense line. But I know there are more than 4 pins.
Sent from my ThinkPad Tablet using xda premium
I would say this is a SW issue. Maybe if we had the kernel source code someone could cook up a custom kernel with that control feature tweeked.
Temetka said:
~
Any chance you could get a proper reading via the docking port on the tablet? I would be curious to see if it is always at 2A. I haven't counted the pins but I don't see why you would need more than VCC+, VCC-, GND and maybe a sense line. But I know there are more than 4 pins.
~
Click to expand...
Click to collapse
The best thing to use is a watt meter if anyone wants to pursue this.
My findings indicated that the dock has a similar issue as the USB charger when the TPT is on.
Maximum current allowed at the dock connector was measured at just over 1A . Dock should charge the battery at a maximum rate of just over 1% per minute provided the battery charge level is below 70%. So if you discharge the battery to around 50% and compare charge rates you should see the difference between TPT on/off.

NST battery voltage shutdown treshold hackable?

Hi,
i use a Nook Simple Touch as typewriter with an usb-keyboard,
which works great thanks to the usb host mode app, or, automated:
an old version of tasker with a plugin to deactivate charging and activate hostmode ( and fastmode...) via shell command after booting.
The problem is, this mode drains the battery really fast,
and charging while using the keyboard, so nececessarily with OTG cable attached, is a bit of a pain in the neck,
because there is only 1 possible sequence of actions how you can enable charging with more than around 100 mA (which would be way too low in this case) while the keyboard is active,
which requires a 16k resistor between GND and ID pin, rebooting, temporarily disconnecting some wires via switch, tapping around etc etc,
(and also does not work well when the nook is completely off ),
so i decided to leave the usb port exclusively for the keyboard,
an remove the internal battery an replace it with a external big 7000mAh or so 1S li-ion pack,
which is charged externally with a lipo module
(while charging, the nook is powered by an ac adapter, power source switching is realised with a relay and a really big capactior to avoid any more complicated possibly failing electronics)
which works great and is very easy to handle,
BUT i really dont like li-ion batterys of any kind because of the fire hazard,
nimh eneloop cant be used because charging in parallel is not a good idea,
so i would like to use lifepo4 chemistry instead,
which has a working woltage between around 3 and 3,6 volts,
but the nook powers down at around 3,65 volts.
A boost/buck converter isnt possible because as the battery drains, the voltage must sink slowly for the nook to make a normal shutdown
and not crash, damage the file system etc, (and also a converter drains quite much battery even if the nook is completely off.)
Question: it would be VERY kind if anyone who has a clue about this could share his opionion on that:
is it possible (if the hardware itself can handle it) to lower the android/nook shutdown voltage to about 3 volts with some rom/software modifications ?
threshold not treshold
Wow, this all seems a bit complicated.
I had never heard of this 16K resistor stuff.
As far as I could tell, the ID pin is only sensed high or low..
Unless I'm mistaken the OMAP3621 ULPI registers only indicate high/low.
The TPS65921B (which is the actual PHY) list 90K as the typical break point.
Of course, there could be a circuit completely external to the ULPI/PHY.
Where did you find out about 16K?
Changing the voltage of everything seems the difficult way to go.
You'd have to modify uboot as well as the charger daemon.
A note: The USB charge pump is pretty inefficient, 55%.
If you were to load the USB to the maximum speced 100mA with a 3V battery, it would be drawing 303mA from the battery!
5V × 100mA / 3v / 55% = 303mA
Oh, you got me confused with your two posts.
When you were talking about ID and 16K did you mean the ID on the battery pack or the ID on the USB OTG?
Renate NST said:
Where did you find out about 16K?
Click to expand...
Click to collapse
wired a 50k pot between gnd and id pin,
in the usb mode app tapped "host" and watched if the led goes an stays on,
if not, lowered the resistance, tried again etc,
as soon it stayed on (at 16k at my device ) used this value as permanent fixed resistor.
with that otg mode keyboard use is possible,
but also at the same time the nook doesnt really believe its in otg mode so charging with 500mA is possible,
if done in this order:
- feed 5v to the + - of the usb cable
- reboot (not always required)
- remove an reinsert usb plug
- hit "host" 2 times, keyboard works and charging with around 500mA works (measured it)
but charging doesnt work when nst ist powered off,
and automount of the keyboard at startup via shell is not possible,
and cable acrobatic is required,
and as you say, usb charging is inefficient.
the other solution with an external battery (at the nst batt terminals) with external charging logic with a relay is a much easyer way,
but depends on a li-ion cell because of the 3,7-4,2 voltages the nook can use,
a lifepo4 ( or 2s li titanate + diode) would be safer and has more cycles but would require the nook
to work with 3 to 3,7 volts, which seems too complicated, changing demons etc whatever that is...
after some research it seems its not really an issue, the newer sanyo/panasonic, samsung, sony, lg powertool/ebike cells seem to be quite safe, as far as youtube shortcircuit etc tests demonstrate.
thanks for the orientational infos
Renate NST said:
Oh, you got me confused with your two posts.
When you were talking about ID and 16K did you mean the ID on the battery pack or the ID on the USB OTG?
Click to expand...
Click to collapse
sorry, i should have used one thread, i suggest ignoring the other one,
where the only request was if the nook battery terminals can survive up to 5v,
here was the request if the nook can be modified to accept at the battery terminals a voltage down to 3v and stay on.
so 3v too complicated, 5v too dangerous,
so i stick with the relay and the li-ion cell, no problem, i was just curious if an improvement would be easily possible.
the battery id resistors have nothing to to with all that, 10k and 30k work fine,
i meant the 5 pin micro usb otg connector, not shorted zero ohms as usual, but 16k.
(but thats obsolete now)
another observation: in some thread you mention you charge the nook while using an usb keyboard,
i tested it and with a normal otg cable, and the usb mode app set to 500 mA oder 1,5 A,
and a 50% charged normal internal battery,
the device draws around 250mA, and the battery gets charged very slowly, or not at all, depending on cpu usage etc.
and if the battery reaches 100% , it continues to draw around 250 mA, which is strange,
because when using a normal, non-otg usb cable,
the device draw only around 100mA when the battery had reached 100%,
so the difference must be used for heating purposes somewhere or overcharge the battery,
which might be a reason for swelling lipos.

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