maemo.org - Talk - View Single Post - The Nokia N810

	igor	2008-03-31 , 22:01
	Posts: 198 \| Thanked: 273 times \| Joined on Jan 2006 @ Helsinki, Finland	#142

Originally Posted by Benson

Igor, you saying there'd be no substantial battery drain from the serial con if you put a pull-up/down on rx? (When not in use, of course.)

If the serial driver is in good shape.

Which might not be the case. The driver alternates between gpio mode and serial:
* after a timeout serial mode is disabled and gpio irq is used to detect activity on the RX line (this trashes the first bit - it would be possible to bitbang the whole first byte and then switch to serial mode, but that's not the case)
* when the irq is rised, the muxing is reverted back to serial mode

But this driver is not part of the deliverables for a stock kernel, so it doesn't get really tested.

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