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Old 06-09-2011, 03:14 PM   #27
hawhill
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Posts: 1,114
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Join Date: Nov 2010
Location: Goettingen, Germany
Device: Kindle Paperwhite, Kobo Mini
Quote:
Originally Posted by mark03 View Post
Any idea if there are C/C++ examples showing the use of those ioctls? I'm intrigued by the various refresh types, flashing vs nonflashing (?), etc. I wonder if the energy consumption scales linearly with the update area size, or if it also depends on the number of black-to-white or white-to-black pixel transitions within that area.
I've attached the code I've written as a gfxdriver for Qt embedded. Grep for the ioctls. But note that I'm only using a single one of them: the fast (but a bit dirty) refresh of rectangular areas. The driver in the kernel seems to be a bit more sophisticated but I didn't come across other code that uses it yet.

BTW, the code expects the kernel eink header file in the compiler's search path (see the include section in the gfxdriver).

Quote:
I'm thinking of writing a bike-computer app for my Kindle. I just need to get a reed switch wired to a keyboard key or side button. How hard could it be...
Well, I'm more in the software side of things :-) But it should be feasible, I think. The buttons generate regular linux input events (which, BTW, is why no special keyboard driver is needed for Qt embedded, just a special keymap).
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