iPhone reports incorrect current draw

[RasmusB]

From a user: "It works perfectly with my Mac and iPad Pro using a usb c adapter, but with my iPhone and a lightning to USB adapter I get the message Arduino draws too much power."

The same user can use the adapter on his Mac and iPad Pro without issue, so it seems the iPhone is more agressive with the current limitation than a proper USB port. SInce it is a "lightning" port and strictly not USB, they might not follow the USB standard fully.

[RasmusB]

There is a fix that requires a change in the core Arduino libraries. I tried implementing that in board.h

#undef D_CONFIG #define D_CONFIG(_totalLength,_interfaces) \ { 9, 2, _totalLength,_interfaces, 1, 0, USB_CONFIG_BUS_POWERED | USB_CONFIG_REMOTE_WAKEUP, USB_CONFIG_POWER_MA(100) }

That did have some effect - USBDeview stopped showing 500mA as the current limit, but it just showed a blank instead of 100mA. Something is not right. The next step will be to try to patch the arudino core library and push it upstream.