Re: [iPAQ] iPaq h3900 i2c bus always busy

Not sure if this will help or not but:

Does the h39 have any SPI devices? If it does they may
be connected to the same pins and are forcing the bus
into that logic state. If that is indeed teh case then
you will need to disable the SPI bus while using I2C.

It is common on many chips to multiplex SPI and I2C as
thier lines are simular but use different logic systems.
I2C is inderterminant when idle where as SPI is high or
low depending on configuration.

On Thu, 7 Dec 2006 17:47:31 +0100
Roland Riegel <roland.riegel.maillist_at_gmx.de> wrote:

>
> Hi to all,
>
> For a university project, I am in the process of implementing sound support
> for the H3900 iPAQ. To communicate with the Philips UDA1380 sound chip, I
> have to get the I2C controller going. And this is where my problems begin.
>
> After initialization of the I2C interface on the PXA250, the SDA and SCL lines
> of the I2C interface stay on a logically low level, such that the I2C bus
> seems busy.
>
> From the Linux code I see that the iPaq contains several ASICs, controlling
> power, clocks, SD card, buttons, LCD backlight and so on. But I couldn't find
> any signs that this also applies to the I2C bus.
>
> Could you please give me some hints on this? I have been searching for a
> solution on this for weeks now, without any progress. My code works on a
> PXA270 based development board, though.
>
> Thanks in advance,
> Roland
> _______________________________________________
> Open Source Software for Compaq iPAQ Handhelds.
> iPAQ mailing list
> iPAQ_at_handhelds.org
> https://handhelds.org/mailman/listinfo/ipaq
> irc://irc.openprojects.net #ipaq
>