First Gen iPad starts on wall charger but not on any iMacs or MacBook Pros.
I have a first gen iPad that will not start up. When I connect it to a wall charger (12W) it starts to boot over and over. If I pull the power, press the home button, and press the power in I get the 'Plug me into USB' graphic. However if I plug it into any of my 12 Macs (modern MacBook Pros and iMacs) the iPad will never start up. I have let it sit on the wall charger for hours just in case the battery was low but I see only the situation I described above. Any suggestions?
iPad, iOS 7, Actually not sure which iOS is inst