User manual

IEC61131 User and Reference Manual
April 22, 2008
424
 The getSFTranslation function returns an entry from the store and forward translation
table. The entry consists of two port and station address pairs.
 The setSFTranslation function writes an entry into the store and forward translation
table. The entry consists of two port and station address pairs. The function checks for
invalid translations; if the translation is not valid it is not stored. The function returns a
status code indicating success or an error if the translation is not valid. A translation is
cleared from the table by writing a translation with both stations set to
DISABLED_STATION (65535).
 The clearSFTranslationTable function clears all entries in the translation table. A
cleared entry has the port set to 0 (com1) and the station set to DISABLED_STATION
(65535).
 The checkSFTranslationTable function checks the translation table for invalid entries. It
returns a status structure indicating if the table is valid and the location and type of the
first error if it is not valid.
Diagnostics Counters
The TeleBUS protocol provides diagnostics counters for each serial port. The counters aid in
determining the source of communication errors. Store and forward messaging provides the
following counters for each communication port. All counters have a maximum count of
65535. Counters roll back to zero on the next event.
 Stored Message Counter: the number of messages received, which qualified for
forwarding. A message qualifies for forwarding if a valid translation is found for the port
and station in the translation table.
 Forwarded Message Counter: the number of messages forwarded (transmitted) on this
port.
Refer to the user manual for the controller and programming environment you are using for
information on the diagnostics counters.
Point–To–Point Protocol (PPP)
SCADAPack 32 and SCADAPack 32P controllers support Point-to-Point Protocol (PPP) on
the serial ports. Any serial port may be configured for the PPP protocol. Once a PPP
connection is established the serial port has access to all IP protocol servers enabled on the
controller.
A serial port configured for PPP supports an auto answer mode when dialed up through a
modem. After answering the modem the serial port performs the login steps according to the
authentication option selected for the port.
PPP provides two authentication protocols, which automates logins - PAP (Password
Authentication Protocol) and CHAP (Challenge-Handshake Authentication Protocol).
PPP settings are configurable for each serial port on the SCADAPack 32 or SCADAPack
32P controller.
An inactivity timeout closes the PPP connection and hangs up the modem when the
connection becomes idle. The timeout may also be disabled. Timeout range is 1 to 65535
minutes (~1092 hours maximum).
When the PPP protocol is selected for a serial port, the serial port must be assigned a
unique IP address, different from the IP address assigned to Ethernet or any other active
PPP connection.
The remote end of a PPP connection may request an IP address from the controller PPP
Server. The PPP Server will provide this IP address if requested.