Connecting LCD via l2c interface on pins other than A5 and A6

Hey, I just made my 16x2 work via l2c interface following this tutorial: http://forum.arduino.cc/index.php?topic=128635.0

The problem I have is, when using this scanner http://playground.arduino.cc/Main/I2cScanner

it only detects my LCD_l2c device (on Arduino Uno) if it is connected to [u]A5[/u] and [u]A6[/u] pins, when I connect it to any other analog pins the scanner won't find anything, but why?

slevinx: when I connect it to any other analog pins the scanner won't find anything, but why?

Why would you expect it to?

Do you know what the "scanner" does?

I thought that l2c pins are logical, not physical and they can exist on any analog pin. My bad i guess.

slevinx:
I thought that l2c pins are logical, not physical and they can exist on any analog pin. My bad i guess.

No, if you wish to use the internal AVR hardware I2C then you are stuck with the pins they are hardwired to inside the chip.

However there are most likely ‘software I2C’ libraries out there somewhere that would allow you to select the pins you wish to use. Do a little searching or maybe wait for someone with first hand knowledge about such libraries.

My point was that you need to understand that the "scanner" is not and never was intended to be searching ports on the MCU chip which as you have gathered by now, would be quite inappropriate not only because the hardware I2C subsystem is fixed to certain ports, but as you clearly know which ports these are and to which you have deliberately connected your I2C device.

The "scanner" is helping you to find the things you do not (necessarily) know, the "invisible" address inside your I2C device which is not a physically observable object. The "guesser" is determining something which you could figure out by carefully examining and testing the traces on the "backpack", but is rather inconvenient to do so.