I2C 0x48 in use by pcf8591

Rabovsky Jonny
i need to attach a NXP-PN532 to i2c-0, but the adr: 0x48 is already in use
by pcf8591.
The problem is, that there is no chance to change the addr of the pn532.

Any suggestions how to change the addr of the pcf8591 ?

Best regards,


Rabovsky Jonny
forgot to tell that i use the nanopi neo

Is the fixed address for the PN532 the same as the PCF8591?  Below you will
find my original response and then I thought if the fixed part can't be
changed then the fixed parts must be different.

Searched the PCF8591 datasheet for 0x48 and don't see any.  Is the fixed
part of the address set at manufacture and where do you find out what it


Are you using the Matrix code?

In my Matrix application I am using


which I find in libfahw-pc8591.h

   #define  PCF8591_ADDRESS             (0x48)  //PCF8591 address

From the datasheet:

Each PCF8591 device in an I 2 C-bus system is activated by sending a valid
address to the device. The address consists of a fixed part and a
programmable part. The programmable part must be set according to the
address pins A0, A1 and A2.

Could that the "fixed part" in that #define be changed and re-compile the

Rabovsky Jonny
i think the PCF8591 ist anywhere at the nanopi neo board, because it is
found by i2cdetect whiout any other modules conneted.

My question is: is it possible to deaktivate the builtin PCF8591 ?

Best regards,

Wonder what they are using it for?  Check on the schematic.

I am sure one could deactivate it but that means some software changes and
a re-compile.