Apple AirPlay



  • We needed a good way to broadcast our iPad's screen to remote workers and clients for demo purposes (using Citrix GoToMeeting/GoToAssist), so we finally investigated Apple's AirPlay because frankly remoting into the Mac via VNC and using the Xcode simulator is about the worst possible way to do it. We found an application called AirServer that installs on your Windows PC and tricks all iOS devices on the network into thinking the PC is actually an Apple TV, meaning it can connect via AirPlay. So we installed AirServer to our conference room PC which is a small mini-tower plugged into a 42" HDTV. Theoretically a window will pop up that has the contents of the iPad's screen, and then we can rebroadcast over GoToMeeting and easily demo. But we couldn't get it working.

    After messing with it, looking at crappy YouTube tutorials and even crappier Apple documentation that just told us to click the AirPlay button on the iPad (a button which as far as we could tell didn't exist) we found hidden in Apple's documentation that the feature only works over Wi-Fi. The conference room PC is hardwired.

    After installing AirServer to a laptop running on Wi-Fi, everything works perfectly.

    Now I know I've been out of college for a few years now, but I do have a minor in computer networking, and last I knew Ethernet and Wi-Fi were layer 2 protocols that are completely transparent to applications and should be completely interchangeable in all circumstances. Software has no idea what the underlying physical topology is, it should Just Work since it should only communicate with the IP layer.

    To use yet another stupid car analogy that I'm typically fond of, this would be like your cattle trailer somehow having a sensor in your fuel tank and leaving the brakes locked up unless you had 91-octane gasoline. Any other grade of fuel and you can't move until you fill up with the "right" stuff. (Or if you're a redneck like me and your pickup has a diesel engine, you're just outta luck.)

    We may be buying a cheap Wi-Fi card for the conference room PC since that'll be much easier than convincing Apple to quit breaking industry standards.


  • SockDev

    So, where's the Ethernet port on an iPad?

    Also, was the router/switch/whatever blocking the AirPlay communication?

     



  • @mott555 said:

    using Citrix

    Take your life.



  • That's standard practice for iTunes.

    iTunes used to (back before I BANNED IT FROM MY HARDWARE FOREVER) require that your iPod/whatever be plugged in to a USB port directly on your computer's motherboard, not into a USB hub.

    Imagine the level of WTFery required for iTunes to even tell if a USB device is plugged into a hub or not.



  • @blakeyrat said:

    Imagine the level of WTFery required for iTunes to even tell if a USB
    device is plugged into a hub or not.
    Under Linux (which I understand the more recent versions of MacOS are based) it's not at all difficult - it's just parsing the path under /sys/bus/usb/devices. A quick google seach would suggest there are enumeration functions to do much the same thing under Windows.



  • @blakeyrat said:

    That's standard practice for iTunes.

    iTunes used to (back before I BANNED IT FROM MY HARDWARE FOREVER) require that your iPod/whatever be plugged in to a USB port directly on your computer's motherboard, not into a USB hub.

    Imagine the level of WTFery required for iTunes to even tell if a USB device is plugged into a hub or not.

    It's probably the power requirements. It tries to charge from it as well as doing disk access. USB hubs are notoriously shit for providing power.

    As for the Airplay thing.. I think you have a firewall issue. I can use Airplay Mirroring from my iPhone/iPad to my iMac running Reflection (Similar app to AirServer.. just for OSX) and it works no problem.

    Similarly, I can do Airplay Mirroring from my MBP which is wired with Ethernet to my AppleTV (which is wireless) without an issue.



  • @PJH said:

    Under Linux (which I understand the more recent versions of MacOS are based)

    Not really at all. The Unix that OSX most resembles is BSD (The Userland is all BSD). The Kernel itself is Mach.

    It's Unix, but not really similar to linux at all other than implementing POSIX.



  • @gu3st said:

    It's probably the power requirements. It tries to charge from it as well as doing disk access. USB hubs are notoriously shit for providing power.

    So it magically knows whether my hub is to spec or not? Because iTunes has PSYCHIC POWERS!?

    Or let's all just admit like sane people that iTunes is fucking retarded.



  • @blakeyrat said:

    @gu3st said:
    It's probably the power requirements. It tries to charge from it as well as doing disk access. USB hubs are notoriously shit for providing power.
    So it magically knows whether my hub is to spec or not? Because iTunes has PSYCHIC POWERS!?

    Or let's all just admit like sane people that iTunes is fucking retarded.

    Its all about the power draw ... iPod/iPhone/i-whatever senses it isn't getting what it needs (and, aren't we all?) and tell iTunes about it.



  • @gu3st said:

    It's probably the power requirements. It tries to charge from it as well as doing disk access. USB hubs are notoriously shit for providing power.

     

    I'd expect hubs to simply short circuit all the power pins that come into them. Why they do something more complex so that they'd have such problem? Is there anything in the USB specs requiring it? (Wouldn't surprize me.)

     



  • @zelmak said:

    Its all about the power draw ... iPod/iPhone/i-whatever senses it isn't getting what it needs (and, aren't we all?) and tell iTunes about it.

    That's fine, but in this case, THAT WASN'T THE PROBLEM. The iPod got plenty of power. iTunes are "pre-emtively" assuming I had a bum USB hub without even checking and FORBIDDING me from using my device on it. And the error message was even vague and confusing.

    DO NOT WORSHIP APPLE. Their products are just as shitty as everybody else's.



  • @zelmak said:

    @blakeyrat said:

    @gu3st said:
    It's probably the power requirements. It tries to charge from it as well as doing disk access. USB hubs are notoriously shit for providing power.
    So it magically knows whether my hub is to spec or not? Because iTunes has PSYCHIC POWERS!?

    Or let's all just admit like sane people that iTunes is fucking retarded.

    Its all about the power draw ... iPod/iPhone/i-whatever senses it isn't getting what it needs (and, aren't we all?) and tell iTunes about it.

    One time I had a weird problem: my PS3 controller was not charging when using a USB extension cable. It was confusing because the cable would work for playing but the controller would not charge. For a while I was thinking there was a problem with the controller but finally I changed the cable and that worked. It would have been convenient to get an alert or something letting me know that the power was not enough to charge.

    Maybe Apple should buy Sony and take over PS3...



  • @Speakerphone Dude said:

    One time I had a weird problem: my PS3 controller was not charging when using a USB extension cable.


    I may be wrong, but I wouldn't necessarily expect a USB extension cable to carry power.


  • SockDev

    @Cad Delworth said:

    @Speakerphone Dude said:

    One time I had a weird problem: my PS3 controller was not charging when using a USB extension cable.


    I may be wrong, but I wouldn't necessarily expect a USB extension cable to carry power.

    The USB spec states that all USB cables have to have a +5V line and a 0V line, and a suitable hub can supply 5V @ 1A.

     



  • @RaceProUK said:

    The USB spec states that all USB cables have to have a +5V line and a 0V line, and a suitable hub can supply 5V @ 1A.

    The dumbest part of the spec says a USB hub isn't required to provide steady power. The smartest part of the spec provides for a way for devices to report back to the computer when they don't have enough power.

    But yes, whether a USB extension has power or not depends on whether it's plugged into a powered or unpowered USB hub.



  • @blakeyrat said:

    @RaceProUK said:
    The USB spec states that all USB cables have to have a +5V line and a 0V line, and a suitable hub can supply 5V @ 1A.

    The dumbest part of the spec says a USB hub isn't required to provide steady power. The smartest part of the spec provides for a way for devices to report back to the computer when they don't have enough power.

    But yes, whether a USB extension has power or not depends on whether it's plugged into a powered or unpowered USB hub.

    then why could I charge the ps3 controller using the same port and a different cable? the one I tried first was working for playing but not charging, the second one did both. no hub involved (unless there is one inside the ps3).



  • @Speakerphone Dude said:

    Maybe Apple should buy Sony and take over PS3...
    Why do you hate PS3?



  • @Speakerphone Dude said:

    then why could I charge the ps3 controller using the same port and a different cable?

    I dunno? Poltergeists? Why the fuck are you asking me? Fix your own damned problems.



  • @blakeyrat said:

    @Speakerphone Dude said:
    then why could I charge the ps3 controller using the same port and a different cable?

    I dunno? Poltergeists? Why the fuck are you asking me? Fix your own damned problems.

    I asked because you stated that "whether a USB extension has power or not depends on whether it's plugged into a powered or unpowered USB hub" and based on the experience I described this is wrong.


  • SockDev

    @Speakerphone Dude said:

    @blakeyrat said:
    @Speakerphone Dude said:
    then why could I charge the ps3 controller using the same port and a different cable?

    I dunno? Poltergeists? Why the fuck are you asking me? Fix your own damned problems.

    I asked because you stated that "whether a USB extension has power or not depends on whether it's plugged into a powered or unpowered USB hub" and based on the experience I described this is wrong.

    So you're absolutely sure the cable was intact (the power line could be broken without you knowing)? Or that the hub's power supply was working (doesn't apply if you didn't use a hub)?



  • @Speakerphone Dude said:

    I asked because you stated that "whether a USB extension has power or not depends on whether it's plugged into a powered or unpowered USB hub" and based on the experience I described this is wrong.

    That's because you have a BROKEN CABLE YOU DUMB FUCK.

    "Hey guys cars start when you turn the key."

    "THEN HOW COME MY CAR DOESN'T START WHEN YOU TURN THE KEY HUH HUH HUH HUH!? Sure it was totaled in that collision with an 18-wheeler BUT I DO NOT UNDERSTAND HOW THIS COULD BE!!! Sure my car is now a 17" tall twisted ball of metal but WHY DOESN'T IT START!"



  • @RaceProUK said:

    @Cad Delworth said:
    [quote
    user="Speakerphone Dude"]One time I had a weird problem: my PS3
    controller was not charging when using a USB extension cable.

    I
    may be wrong, but I wouldn't necessarily expect a USB extension cable
    to carry power.
    The USB spec states that all USB cables have to
    have a +5V line and a 0V line, and a suitable hub can supply 5V @ 1A.[/quote] @zelmak said:
    Its all about the power draw ...
    iPod/iPhone/i-whatever senses it isn't getting what it needs and tell iTunes about it.
    I wouldn't be surprised if the problem was caused by the length of the extension cable.  Although the USB spec says the total cable length limit is 5 meters, I've found that some devices have problems beyond 3 meters.



  • @blakeyrat said:

    @Speakerphone Dude said:
    I asked because you stated that "whether a USB extension has power or not depends on whether it's plugged into a powered or unpowered USB hub" and based on the experience I described this is wrong.

    That's because you have a BROKEN CABLE YOU DUMB FUCK.

    As stated (a few times), the cable was working fine for playing but it was not *charging* the controller. It was also working fine to plug a usb drive to my computer. That is not a typical behavior for a "broken" cable.

    I was able to use a different cable to charge the controller. So I'm still not sure if the cable was partially broken or if there are different classes of cables, but it is now obvious that you don't know either so thanks for nothing.



  • @El_Heffe said:

    @RaceProUK said:

    @Cad Delworth said:
    [quote
    user="Speakerphone Dude"]One time I had a weird problem: my PS3
    controller was not charging when using a USB extension cable.

    I
    may be wrong, but I wouldn't necessarily expect a USB extension cable
    to carry power.
    The USB spec states that all USB cables have to
    have a +5V line and a 0V line, and a suitable hub can supply 5V @ 1A.
    @zelmak said:
    Its all about the power draw ...
    iPod/iPhone/i-whatever senses it isn't getting what it needs and tell iTunes about it.
    I wouldn't be surprised if the problem was caused by the length of the extension cable.  Although the USB spec says the total cable length limit is 5 meters, I've found that some devices have problems beyond 3 meters.

    [/quote]

    I bought both cables at the same small PC shop and I was sure they were identical but after looking carefully they are not. They have the same length (about 2 meters) but the one that works for charging has a slightly less bulky female connector (metal part). This is a bit weird but I guess that's what happen when buying cheap parts instead of getting ripped off at Best Buy.

    I have yet to find out if there are different types of cables, so far no luck.



  • @Speakerphone Dude said:

    So I'm still not sure if the cable was partially broken or if there are different classes of cables,

    Yes, there are two classes: Broken and Not Broken.

    @Speakerphone Dude said:

    but it is now obvious that you don't know either so thanks for nothing.

    I do too know. Poltergeists. Duh.


  • SockDev

    @Speakerphone Dude said:

    @blakeyrat said:
    @Speakerphone Dude said:
    I asked because you stated that "whether a USB extension has power or not depends on whether it's plugged into a powered or unpowered USB hub" and based on the experience I described this is wrong.

    That's because you have a BROKEN CABLE YOU DUMB FUCK.

    As stated (a few times), the cable was working fine for playing but it was not *charging* the controller. It was also working fine to plug a usb drive to my computer. That is not a typical behavior for a "broken" cable.

    I was able to use a different cable to charge the controller. So I'm still not sure if the cable was partially broken or if there are different classes of cables, but it is now obvious that you don't know either so thanks for nothing.

    USB cables have 4 wires in them - only the +5V one needs to be broken to prevent charging. Also, the controller still works for playing because those signals go via Bluetooth, not USB.

    I don't know why I'm helping you, since you obviously don't want to listen to anyone. I've come across your type before, who thinks that they're the God of All Knowledge, and go for the jugular when anyone says something you don't agree with, but hell, I find your pathetic ranting too entertaining to just ignore you. Maybe I should use my /. signature on here, as it really is fun to feed the trolls sometimes - it's comforting to know there's someone out there stupider than myself.

    USB on Wikipedia



  • @RaceProUK said:

    @Speakerphone Dude said:

    @blakeyrat said:
    @Speakerphone Dude said:
    I asked because you stated that "whether a USB extension has power or not depends on whether it's plugged into a powered or unpowered USB hub" and based on the experience I described this is wrong.

    That's because you have a BROKEN CABLE YOU DUMB FUCK.

    As stated (a few times), the cable was working fine for playing but it was not *charging* the controller. It was also working fine to plug a usb drive to my computer. That is not a typical behavior for a "broken" cable.

    I was able to use a different cable to charge the controller. So I'm still not sure if the cable was partially broken or if there are different classes of cables, but it is now obvious that you don't know either so thanks for nothing.

    USB cables have 4 wires in them - only the +5V one needs to be broken to prevent charging. Also, the controller still works for playing because those signals go via Bluetooth, not USB.

    The ps3 controller is not using Bluetooth when the controllers is connected via USB (which is also how a Bluetooth problem can be fixed). And since the controller was working with the cable but not working without the cable (having not been recharged), it was a weird behavior leading me to believe at first that the controller battery was the problem. If the controller had not worked with the cable it would have been faster to figure out that the cable was "broken" (which I'm still not sure is the case).

    Also let me repeat (again): the cable is working for connecting a USB drive to my PC anyways. That does not constitute a typical "broken" behavior.

    It's possible that the cable has been poorly built and that one of the wires is broken or disconnected; or it is also possible that some companies (probably chinese) sell two types of cables: with and without the power wire. I don't know and haven't found reliable information so far.

    @RaceProUK said:

    I don't know why I'm helping you, since you obviously don't want to listen to anyone. [snip "my pussy hurts" rant]

    I did not ask for help because I already know how to solve the problem, as stated previously. I posted a comment about a problem that I've experienced and that would have been less annoying if the console had been able to warn me that the usb cable was not providing power to recharge the controller. The only feedback I received was the typical blinking on the controller, and the fact that it was working with the cable.

    So maybe the problem is not that I don't want to listen to anyone, but rather that you don't read posts before putting on your cheap superman uniform and jumping in with useless wikipedia information.



  • Let's just all point the finger at the guilty party here: why do you own a PS3 and not an Xbox? What kind of Japanophile freak are you?



  • @blakeyrat said:

    Let's just all point the finger at the guilty party here: why do you own a PS3 and not an Xbox? What kind of Japanophile freak are you?

    I also have an Xbox (+kinect). I used to be a snob looking down on Xbox people, until Sony got hacked time and again (and added something like $1.25 on my e-wallet to make amends). Nowadays I use the ps3 mostly to watch movies.

    Hopefully one day there will be a plugin to control movies playback with the kinect. That way the console would know when I get up to go grab a beer (or get a blow-job from the bathroom hooker) and put the movie on pause. Would be awesome also to have "natural gesture" commands, like putting on sunglasses would start an episode of CSI Miami, or doing a roundhouse kick would start a Chuck Norris movie.

    There are so many useful projects to be done, yet most startups waste their money on stupid twitter extensions and then cry because they get f*cked by the new API. I would gladly pay $5 for a roundhouse kick movie trigger but nobody will ever get a dime from me for anything twitter or facebook.



  • @Speakerphone Dude said:

    Hopefully one day there will be a plugin to control movies playback with the kinect.

    You can do that with the Netflix app. Kinda.

    @Speakerphone Dude said:

    (or get a blow-job from the bathroom hooker)

    You have a live-in hooker? In more than one room of your house? (Thus the need to identify the hooker by the name of the room in which they reside?)

    @Speakerphone Dude said:

    Would be awesome also to have "natural gesture" commands, like putting on sunglasses would start an episode of CSI Miami, or doing a roundhouse kick would start a Chuck Norris movie.

    Ha. Ha. Ha. You are a comedy legend. Ha. Ha. Ha. Chuck Norris jokes in 2012. HOW TIMELY!

    EDIT: BTW the only way you could possibly look down upon an Xbox compared to a PS3 is by simply NEVER EVER USING AN XBOX. Because, seriously, EVERYTHING Sony did was a half-assed rip-off of Microsoft's features. EVERYTHING. Trophies? Half-assed rip-off of Achievements. PSN? Half-assed rip-off of Xbox Live. That stupid magic wand motion controller thing I can't remember the name of? ... ok that's a half-assed ripoff of Nintendo's Wii Motion. Because neither they nor Nintendo can get within 200 miles of Kinect. Because Japanese gaming companies have been shit for the last 10 years, even if people are just now figuring it out.



  • @blakeyrat said:

    @Speakerphone Dude said:
    (or get a blow-job from the bathroom hooker)

    You have a live-in hooker? In more than one room of your house? (Thus the need to identify the hooker by the name of the room in which they reside?)

    Not at home. But I travel a lot for work and because I am awesome my clients insist to put me in nice hotel suites where there are Xbox Kinects and bathroom hookers.

    Bathroom hookers are great because they give you a towel when you go wash your hands, like those old dudes in old-fashioned restaurants bathrooms. Some will even dry your hands, so it feels like doctors getting ready to enter the surgery room with the head nurse helping them. But bathroom hookers are provided as-is so they can be older (like 30) or not the right color; if you want more than a quick blowjob or handjob it's better to get a proper escort from the concierge so you can give specifications. In most hotels they also don't like when you get rough with bathroom hookers so if you feel like slapping someone around you need a proper escort. They also won't watch a movie with you or go in the living room and bounce up and down on one foot while you jerk off (if you are into that). They offer basic services.

    In my experience bathroom hookers are not itemized on the invoice, they come with the suite, while escorts are itemized under "guest services" (where you get also billed for the good coke scored from the concierge if you are into drugs).

    @blakeyrat said:

    @Speakerphone Dude said:
    Would be awesome also to have "natural gesture" commands, like putting on sunglasses would start an episode of CSI Miami, or doing a roundhouse kick would start a Chuck Norris movie.

    Ha. Ha. Ha. You are a comedy legend. Ha. Ha. Ha. Chuck Norris jokes in 2012. HOW TIMELY!

    Associating roundhouse kicks with Chuck Norris is not the same a making a Chuck Norris joke. However the more I think about it, the more it appears suboptimal as there could be a conflicting gesture to start watching Roadhouse. This raises the interesting question: how is a gesture stored? A series of coordinates and time? If I had a Kinect Playback Gesture startup (with gestures that do more than basic commands) I would create a vibrant community where people could exchange Gesture Recognition Scripts or even post them via a public web service.



  • @Speakerphone Dude said:

    I would create a vibrant community where people could exchange Gesture Recognition Scripts or even post them via a public web service.

    And you would access the service with a gesture which needs to be downloaded from that very service!



  • @Ben L. said:

    @Speakerphone Dude said:
    I would create a vibrant community where people could exchange Gesture Recognition Scripts or even post them via a public web service.

    And you would access the service with a gesture which needs to be downloaded from that very service!

    Your tag is wrong. This is not recursion, this is mutual exclusion, which is not the contrary but possibly the opposite.

    I declare the pedantic part of the discussion open. Play ball!


  • SockDev

    @Speakerphone Dude said:

    I would create a vibrant community where people could exchange Gesture Recognition Scripts or even post them via a public web service.

    monks chanting in background

    Thus spake the Almightly Speakerphone, God of All Technology. Come, let us praise him, for we are but humble in his prescence.

    Sorry mate, but you walked right into that one :P


  • BINNED

    @Speakerphone Dude said:

    Maybe Apple should buy Sony and take over PS3...

    All hail Playstation Pippin!


  • SockDev

    @Speakerphone Dude said:

    cheap superman uniform

    Actually, I have a Batman costume. Don't worry though, next time I'll send Dick Grayson instead.



  • @El_Heffe said:

    Although the USB spec says the total cable length limit is 5 meters, I've found that some devices have problems beyond 3 meters.
    Yup - my scanner (HP 5590 - has it's own power supply) won't work with 3 and 5m long USB cables.
    @Speakerphone Dude said:
    They have the same length (about 2 meters) but the one that works for charging has a slightly less bulky female connector (metal part).
    Is it possible that one cable has mini-A connector, and the other mini-B? They look nearly identical, and one will usually fit into the other's slot, but the contact won't be as good, which could explain your problems.
    @RaceProUK said:
    Also, the controller still works for playing because those signals go via Bluetooth, not USB.
    When the PS3 controller is connected with cable, it doesn't use bluetooth.



  •  What used to really bug me was old Blackberrys (about 6-7 years ago)

    I had a friend who was making such a big deal about how it came with one of those mini-b types (little bit more trapezoid than the micro-b connectors) so he would always be able to charge it anywhere as those types of cables were a dime a dozen and got used for everything from webcams, usb hubs, card readers, etc. The WTF about it all was that the Blackberry would only charge if it recognised that the sync software was installed on the computer. It did charge when plugged into a standalone power source that wasn't connected to a turned on computer. What genius thought that was a good idea? The WTFery involved to actively check to see if it was receiving input over the data lines of the USB cable and then refuse to charge if it didn't get a response from the sync software is ridiculous.


  • SockDev

    @ASheridan said:

     What used to really bug me was old Blackberrys (about 6-7 years ago)

    I had a friend who was making such a big deal about how it came with one of those mini-b types (little bit more trapezoid than the micro-b connectors) so he would always be able to charge it anywhere as those types of cables were a dime a dozen and got used for everything from webcams, usb hubs, card readers, etc. The WTF about it all was that the Blackberry would only charge if it recognised that the sync software was installed on the computer. It did charge when plugged into a standalone power source that wasn't connected to a turned on computer. What genius thought that was a good idea? The WTFery involved to actively check to see if it was receiving input over the data lines of the USB cable and then refuse to charge if it didn't get a response from the sync software is ridiculous.

    It may be the case that the PC isn't activiating the +5V line automatically, whereas a charger holds that line active permanently. I know I've had USB-capable phones in the past that required a specific driver to charge from a PC.

    If it is the case, then the PC will be keeping the +5V line off to prevent accidental damage to connected peripherals.



  • @ASheridan said:

     What used to really bug me was old Blackberrys (about 6-7 years ago)

    I had a friend who was making such a big deal about how it came with one of those mini-b types (little bit more trapezoid than the micro-b connectors) so he would always be able to charge it anywhere as those types of cables were a dime a dozen and got used for everything from webcams, usb hubs, card readers, etc. The WTF about it all was that the Blackberry would only charge if it recognised that the sync software was installed on the computer. It did charge when plugged into a standalone power source that wasn't connected to a turned on computer. What genius thought that was a good idea? The WTFery involved to actively check to see if it was receiving input over the data lines of the USB cable and then refuse to charge if it didn't get a response from the sync software is ridiculous.

     

     

    wikipedia regarding this - make sense to me.  You can always force it to draw as much current as possible from a PC without software by splitting the lead and turn it into a DCP  :

     

    The USB Battery Charging Specification of 2007 defines new types of USB ports, e.g., charging ports.[44] As compared to standard downstream ports,
    where a portable device can only draw more than 100 mA current after
    digital negotiation with the host or hub, charging ports can supply
    currents above 0.5 A without digital negotiation. A charging port
    supplies up to 500 mA at 5 V, up to the rated current at 3.6 V or more,
    and drop its output voltage if the portable device attempts to draw more
    than the rated current. The charger port may shut down if the load is
    too high.

    Charging ports exist in two flavors: charging downstream ports (CDP), supporting data transfers as well, and dedicated charging ports (DCP), without data support. A portable device can recognize the type of USB port from the way the D+ and D- pins are connected. For example, on a dedicated charging port, the D+ and D- pins are shorted. With charging downstream ports, current passing through the thin ground wire may interfere with high-speed data signals. Therefore, current draw may not exceed 900 mA during high-speed data transfer. A dedicated charge port may have a rated current between 0.5 and 1.5 A. There is no upper limit for the rated current of a charging downstream port, as long as the connector can handle the current (standard USB 2.0 A-connectors are rated at 1.5 A).

    Before the battery charging specification was defined, there was no standardized way for the portable device to inquire how much current was available. For example, Apple's iPod and iPhone chargers indicate the available current by voltages on the D- and D+ lines. When D+ = D- = 2V, the device may pull up to 500 mA. When D+ = 2.0 V and D- = 2.8 V, the device may pull up to 1000 mA of current.

     


     



  • @RaceProUK said:

    It may be the case that the PC isn't activiating the +5V line automatically, whereas a charger holds that line active permanently. I know I've had USB-capable phones in the past that required a specific driver to charge from a PC.

    If it is the case, then the PC will be keeping the +5V line off to prevent accidental damage to connected peripherals.

     

    It wasn't a case of that unfortunately, and we tested across a whole office worth of computers (about 10) (we were in IT, so the wasting time was classed as for research purposes). I don't get how other phones were fully capable of charging without needing drivers installed yet this newer (at the time) phone couldn't. I could think of many sane reasons, but they each get discarded when you bring into context all the other phones that have gotten this simple thing right both before and since. 

     



  •  when i had an iphone i had to mod a charge port in my car so iphone would charge from it by putting voltage divider on the (otherwise connected) D- and D+ for 2ish and 2.5v - this worked OK with a crackberry. God i hated every inch of that crackberry, the iphone was ok for 3 months, then i got bored of it (AND never allowing me to read my previously received emails unless i have signal - WTF was that design all about).




  • @Helix said:

    (AND never allowing me to read my previously received emails unless i have signal - WTF was that design all about).
    Ah, but that's an Apple©®™ Feature©®™! It allows you to see only the most up-to-date versions of your old emails, just in-case they, y'know, change or something.

     



  • @ASheridan said:

    @Helix said:

    (AND never allowing me to read my previously received emails unless i have signal - WTF was that design all about).

    Ah, but that's an Apple©®™ Feature©®™! It allows you to see only the most up-to-date versions of your old emails, just in-case they, y'know, change or something.

    As much as I enjoy and encourage bashing Apple, senselessly or otherwise, I must point out he was talking about BlackBerry.



  • @mott555 said:

    @ASheridan said:
    @Helix said:

    (AND never allowing me to read my previously received emails unless i have signal - WTF was that design all about).

    Ah, but that's an Apple©®™ Feature©®™! It allows you to see only the most up-to-date versions of your old emails, just in-case they, y'know, change or something.

    As much as I enjoy and encourage bashing Apple, senselessly or otherwise, I must point out he was talking about BlackBerry.

    No, that comment was clearly about his iPhone.


  • SockDev

    @boomzilla said:

    @mott555 said:
    @ASheridan said:
    @Helix said:

    (AND never allowing me to read my previously received emails unless i have signal - WTF was that design all about).

    Ah, but that's an Apple©®™ Feature©®™! It allows you to see only the most up-to-date versions of your old emails, just in-case they, y'know, change or something.

    As much as I enjoy and encourage bashing Apple, senselessly or otherwise, I must point out he was talking about BlackBerry.

    No, that comment was clearly about his iPhone.

    if only you'd said Apple, that would have set up a banana-phone joke...



  • @RaceProUK said:

    @boomzilla said:
    No, that comment was clearly about his iPhone.

    if only you'd said Apple, that would have set up a banana-phone joke...

    I am certainly grateful for small mercies.



  • @RaceProUK said:

    @boomzilla said:
    @mott555 said:
    @ASheridan said:
    @Helix said:
    (AND never allowing me to read my previously received emails unless i have signal - WTF was that design all about).
    Ah, but that's an Apple©®™ Feature©®™! It allows you to see only the most up-to-date versions of your old emails, just in-case they, y'know, change or something.

    As much as I enjoy and encourage bashing Apple, senselessly or otherwise, I must point out he was talking about BlackBerry.

    No, that comment was clearly about his iPhone.

    if only you'd said Apple, that would have set up a banana-phone joke...
    You mean Pearphone

     

     



  •  Things have certainly gone pearshaped.



  • @ASheridan said:

    It wasn't a case of that unfortunately, and we tested across a whole office worth of computers (about 10) (we were in IT, so the wasting time was classed as for research purposes). I don't get how other phones were fully capable of charging without needing drivers installed yet this newer (at the time) phone couldn't. I could think of many sane reasons, but they each get discarded when you bring into context all the other phones that have gotten this simple thing right both before and since.

    I seem to recall Windows 2000 and Windows XP would cut the USB power if the device didn't have a driver at all. I'm not sure exactly what Microsoft's reasoning was for this, but you could easily "trick" it by installing a generic driver (like USB Mass Storage) and just not making any volumes available.


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