B&B Electronics VFG3000 - Manual - Manual (Page 189)

U SING THE S ECURITY S YSTEM S PECIFYING T AG S ECURITY
R EVISION 1 P AGE 173
• The Password property is used to specify an initial password for this user. The
password is case-sensitive and comprises alphanumeric characters. Note that if
the Override Existing box is checked, any changes made to this password from
the Fieldbus Gateway itself will be overridden when this database is downloaded
to the Gateway.
• The System Rights properties are used to grant a user the ability to perform
certain system actions. The properties relating to password changes are self-
explanatory, while the user of Maintenance Mode is described above.
• The Custom Rights properties are used to grant a user certain rights which may
then be used within the database to allow access to groups of tags or display
pages. The exact usage of these rights is up to the system designer.
S
PECIFYING
T
AG
S
ECURITY
Each writable tag has a tab called Security which is used to define the access control and
write logging settings for that tag. If you do not define specific settings, the system will use
the appropriate default settings, depending on whether it is mapped to external data.
S
PECIFYING
P
AGE
S
ECURITY
The access control settings for a display page are defined via the Properties dialog…
Once again, if no setting is defined, default settings will be used.
T
HE
S
ECURITY
M
ANAGER
P
RIMITIVE
The Security Manager Primitive is used to display the names of users present on
the system. It can be used to change a user’s password, depending on the rights
allocated to the active user.
The only editable properties of this primitive define the fonts to be used, and whether or not
the primitive should be displayed. Refer to other primitives for descriptions of these settings.
S
ECURITY
R
ELATED
F
UNCTIONS
Please refer to Appendix A later in this manual for details on the UserLogOn() ,
UserLogOff() and TestAccess() functions. This third function is useful when changing
many values from within a program, as it allows you to force an access check early in the
code to avoid making changes only to have later operations fail due to insufficient user rights.