Re: [Gumstix-users] i2c on gumstix overo fire with summit board

[Dave H. <dhy...@gm...>]

Hi Yifei,

On Tue, May 11, 2010 at 1:48 AM, SHI yifei <shi...@gm...> wrote:
> HI
> In my boot log, it also has this: i2c_omap i2c_omap.3: bus 3 rev3.12 at 400
> kHz.
> So does it mean the i2c bus should work well?

That means that the driver is in fact present.

> I double checked the pins i am using, they are at right place. And i dont
> have any other devices on i2c bus.

Well that's weird then. The MCP23017 datasheet implies an address of
0x2x, but if it's showing up at 0x5x then try using that instead. I'd
double check the chip though and make sure that it is in fact an
MCP23017.

The fact that you're seeing any device at all means that the SDA and
SCL lines must be toggling.

-- 
Dave Hylands
Shuswap, BC, Canada
http://www.DaveHylands.com/