GTA03 LED controller: LP5521
andy at openmoko.com
Wed Jan 14 10:48:26 CET 2009
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Somebody in the thread at some point said:
| Joerg Reisenweber wrote:
|> I don't think this direct CPU GPIO thing would be a better alternative
|> to an emergency driver directly accessing I2C to force some few bytes
|> into the LED controller.
| A device can block the I2C bus indefinitely under some circumstances,
| e.g., if you're unlucky enough to crash while in the middle of an I2C
| transfer, SCL is low, and the device is sending a 0 or an ACK.
The devices we have on GTA02 are simple state machines for I2C action,
all of them are rated at 400Hz so they won't have SCK-driving
arrangements anyway to enforce slower SCK.
So I don't think we need to worry about this kind of scenario.
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