With the AM503B, without a GPIB interface, no write processes (except for everything that concerns the operation of the device) can be triggered on the SRAM (PCF8570).
I started by recording the data when "booting" the device and then looking for the value "25000".
This is the "default" value for the calibration data. This is how I found the addresses for these values.
The serial number is in a different area of the SRAM.
In addition, each time a button is pressed on the front panel, this information is saved in the SRAM.
After a "power-up" this information is read back again.
If you want, I can add some screenshots of the data transfer and the connection with the logic analyzer to the "PHOTOS" folder.