Lpc2000

Hi group,

I need some help getting my i2c to run.
An lpc2106 board (Master) is connected to a 5V mega16 AVR.
No interrupt is sent, after the start bit is set.

I have tested the pins P0.2, P0.3, and P0.4 (reference) in GPIO mode,
and here is, what I find:

P0.4 works fine - it jumps between 0V and 3.3V.

When P0.2 (SCL) is setup with a pull-up resistor (10k ohm) to the 
3.3V supply voltage, it also jumps between 0V and 3.3V. When the
resistor is removed the numbers are only 0V and 80 mV.

When P0.3 (SDA) has a pull-up resistor (10kOhm) connected, the
voltage is constant at 0.245V - no float what so ever. After the 
resistor is removed, the pin jumps between 0V and 4 mV

Have my worst fears been realized - have I destroyed something??

Any help would be appreciated!
- Nana

>I need some help getting my i2c to run.
>An lpc2106 board (Master) is connected to a 5V mega16 AVR.
>No interrupt is sent, after the start bit is set.
>
>I have tested the pins P0.2, P0.3, and P0.4 (reference) in GPIO mode,
>and here is, what I find:
>
>P0.4 works fine - it jumps between 0V and 3.3V.
>
>When P0.2 (SCL) is setup with a pull-up resistor (10k ohm) to the
>3.3V supply voltage, it also jumps between 0V and 3.3V. When the
>resistor is removed the numbers are only 0V and 80 mV.
>
>When P0.3 (SDA) has a pull-up resistor (10kOhm) connected, the
>voltage is constant at 0.245V - no float what so ever. After the
>resistor is removed, the pin jumps between 0V and 4 mV
>
>Have my worst fears been realized - have I destroyed something??
You NEED pull-up on both pins! A value in the range 2K2 to 10K is good
(depends on desired speed and power-consumption).
I think you should try another new chips. Seems that you destroyed SDA pin.

regards -
Henry

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