4 ms·

Windows (may even be the USB specification itself) will not deliver more than X mA to a device unless a driver is installed to request > X mA OS X obviously is

by seabee 16y ago

Windows (may even be the USB specification itself) will not deliver more than X mA to a device unless a driver is installed to request > X mA OS X obviously is aware of iDevices so it charges without you knowing any wiser. Windows needs the driver.

noonespecial 16y ago
As this unfolded (the comments) I realized I very well might be talking out of my ass, and I hate when people do that to me so I grabbed my gear to divine the electronic truth. Here are some facts I learned: My MacBook pro gladly puts out more than 1100ma @5v no matter whats connected and no matter what "handshaking" occurred (or didn't). Its a little scary really. My iPad does charge albeit very slowly even when it says "not charging". When it does so, it consumes about 750ma (thus, breaking the spec anyway in a strict sense). It stops charging if you turn it on and just runs from usb power. So its kind of telling the truth, when it says "not charging" on the screen, it actually isn't. The ipad increases charge to around 950ma when it gets the OK from an Apple Approved device. (my MacBook, only when in OSX mode) When connected to my palm pre's "dumb charger" the ipad does the "not charging" thing @750, even though the pre's charger can deliver 1500ma. The official Apple wall charger seems to deliver about 5.5v and nearly 1000ma to the pad. It seems the choice is actually left to the iPad itself whether to sip or slurp and it does this by detecting what its connected to. (or rather, what it isn't connected to) In conclusion, this operational profile is frustrating. "Purposely broken" may have been too strong but they didn't go through any extra effort to make my user experience stellar if I elected not to go the full monty on apple gear. But what does it really mean to me? I can't charge my 'pad on the damn plane on that freakishly long SF to Sydney and watch all the back episodes of "Mad Men", using that nifty USB jack on Qantas' new A380. Bummer.

by seabee 16y ago

noonespecial 16y ago

As this unfolded (the comments) I realized I very well might be talking out of my ass, and I hate when people do that to me so I grabbed my gear to divine the electronic truth. Here are some facts I learned: My MacBook pro gladly puts out more than 1100ma @5v no matter whats connected and no matter what "handshaking" occurred (or didn't). Its a little scary really. My iPad does charge albeit very slowly even when it says "not charging". When it does so, it consumes about 750ma (thus, breaking the spec anyway in a strict sense). It stops charging if you turn it on and just runs from usb power. So its kind of telling the truth, when it says "not charging" on the screen, it actually isn't. The ipad increases charge to around 950ma when it gets the OK from an Apple Approved device. (my MacBook, only when in OSX mode) When connected to my palm pre's "dumb charger" the ipad does the "not charging" thing @750, even though the pre's charger can deliver 1500ma. The official Apple wall charger seems to deliver about 5.5v and nearly 1000ma to the pad. It seems the choice is actually left to the iPad itself whether to sip or slurp and it does this by detecting what its connected to. (or rather, what it isn't connected to) In conclusion, this operational profile is frustrating. "Purposely broken" may have been too strong but they didn't go through any extra effort to make my user experience stellar if I elected not to go the full monty on apple gear. But what does it really mean to me? I can't charge my 'pad on the damn plane on that freakishly long SF to Sydney and watch all the back episodes of "Mad Men", using that nifty USB jack on Qantas' new A380. Bummer.