GE 90-30 PLC Switch User Manual

Naming Architecture
This appendix gives an overview of the naming architecture concepts used within GE
Fanuc Series 90 PLCs.
The goal of the naming architecture is to provide users the ability to think of their
Ethernet Interfaces in terms of a symbolic name rather than a numerical address. Use of
this symbolic name will be capable in all areas that require an IP Address. This name,
commonly referred to as the Network Address Name, can be constructed from the
following character set:
a-z, A-Z, 0-9, ‘~!@#$%^&*()_+|-=\{}[]:”;’<>?,./
Name Assignment
Name assignment implies associating a symbolic name to an IP address. There exist
three scenarios where name assignment occurs.
The first deals with the Ethernet Interface using a default mechanism for assigning itself
a Network Address Name. If the Ethernet Interface has no source for a Network Address
Name at startup, it will generate a name in the form “cmm742_xxxxxx” where xxxxxx is
the ASCII representation of the last six hexadecimal digits of the MAC address used by
this module. This mechanism will be used whenever there exists no other configuration
source for a name (neither module configuration nor backup data).
The second scenario deals with the assignment of a Network Address Name to the
Ethernet Interface by the PLC Programmer (if supported). The Network Address Name
is configured for an Ethernet Interface and stored into the PLC. If a Network Address
Name is not configured at the PLC Programmer, a Network Address Name may be
locally defined or modified at the Ethernet Interface with the station manager command
chmyname. This command is documented in the TCP/IP Ethernet Communications Station
Manager Manual, GFK-1186.
The third scenario dealing with name assignment involves the building of a Name Table
which contains a mapping of symbolic names to associated IP addresses. This table may
be created at the PLC Programmer (if supported) and stored into the PLC. If a Name
Table is not created at the PLC Programmer, a local Name Table may be created within
the Ethernet Interface; entries in the local table are added, edited, and deleted using the
station manager command “chnametbl.” This command is documented in full detail in the
TCP/IP Ethernet Communications Station Manager Manual., GFK-1186.