Fxm is the format used by Fx-Interface Pro to store any kind of data excepted backups. Fxm files are ended by .fxm
In fxm files, backup are stored in the middle of other data. For a 64ko calculator, the raw backup is from the 4218 octet to the 67705 octet (both included).
Here is a python script to extract the backup:
fxm_file = open('backup.fxm','rb') ctn = fxm_file.read(67706) fxm_file.close() bak = ctn[4218:] raw_file = open('backup.cafix','w') raw_file.write(bak) raw_file.close()