Generic GPIO I2C bitbang kernel question
Bill Gatliff
bgat at billgatliff.com
Fri Oct 2 14:26:53 EDT 2009
Brian Hutchinson wrote:
>
> Good talking to you again at ESC!
Likewise! When are you going to give an actual presentation? :)
> I've sense been able to get the i2c-core bit banging to work! I wrote
> a user land app to write to a eepot and it is working now. The
> problem was in fact the line I mentioned that was driving SDA high
> when it should have been turned into a input to look for the ACK from
> the slave.
Aaah. With I2C, you never "drive" the line high--- that's what the
pullups are for.
So if you want to output a zero, you drive the line low. To output a
one, you float the line.
b.g.
--
Bill Gatliff
bgat at billgatliff.com
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