Return codes

Start of changeRegister 15 contains a return code indicating the success or failure of the request. Possible return codes (in decimal) are:End of change
0
The environment is no longer prepared for a sequence of calls.
4
The function code is not valid.
8
The indicated environment was already active; no action taken.
16
The token is not valid.
20
The token was not used in a start_seq call.