Lpc2000

--- In lpc2000@yahoogroups.com, "Andrew Berney" <amb@...> wrote:
>
> Currently there are no pull ups on either P0.2 or P0.3... we're not
using
> I2C but I'm guessing they're still required even for GPIO use.
> 

You have to put pullups on each pin that can be used with I2C since
these pins are open collector.
I found a similar problem using LPC2138 (it has 2 I2C units so there
are 4 open collector pins).
Effectively this is written in VERY small character in the pin
configuration section of user manual.
Regarding other pins you have to pull them (to gnd or vcc) if they are
programmed as inputs, to avoid a floating voltage.

Carlo Barbaro