Better interrupt APIs

[bnewbold]

Original author: [email protected] (April 11, 2011 18:43:55)

See:

http://forums.leaflabs.com/topic.php?id=720

Users would like a more convenient interface for attaching interrupts to all sorts of events. It seems like DMA is probably the backend to choose for most of these situations (ADC conversion, USART character reception, etc.), but the CAN/USB IRQ sharing issue brought up by x893 is a good point: we should allow a #define to bring in a CAN IRQ handler defined by the user.

Original issue: http://code.google.com/p/leaflabs/issues/detail?id=62