Return code 11: Invalid subindex
The requested subindex is invalid.
Return code 12: Invalid language
Not used with F6/S6.
Return code 13: Invalid address
The requested parameter is not supported by the device.
Return code 14: Function not possible
The request is currently not possible. Some parameters can only be written with modula-
tion switched off. In this case a request with modulation switched on is acknowledged
with return code 14.