Rockwell Automation 57C620 AutoMax Programming Executive Version 3.8 - Manual (Page 269)

NĆ1 Tokens and Locking
Appendix N
Tokens and Locking
Tokens provide a means of writeĆprotecting the databases and tasks for one or
more racks or an entire system when using the AutoMax Programming Executive
in a network environment. Locking will prevent more than one user at a time from
changing the same database information.
Tokens
When more than one copy of a file exists, there is the potential that the various
copies will be modified independently. This problem can occur in AutoMax when
part or all of a system is transferred to another workstation. To avoid losing
independent changes, only one copy can be considered the source" copy. All
other copies must be considered to be readĆonly. Tokens are used in AutoMax to
ensure that only one copy can be modified.
A token is an abstract entity which represents the ability to modify a group of files.
There will be one token to represent the system database group and the system
and section documentation files, and a separate token for each rack and its
associated files. If a copy of the rack file holds" the token, that copy can be
modified. If a copy does not hold the token, it cannot be modified. Only one copy
of the system files or of a rack file can hold the token. If a user attempts to make
modifications without the token, the user will receive an error message like the
following:
When a system or rack is created, a token is created along with it. Whenever the
system (or rack) is transferred using the Transfer command in AutoMax, the user
has the option of transferring the token with it. If the token is transferred out, the
original copy becomes readĆonly and only the destination copy can be modified.