Service manual

181Appendix I Using MODBUS Protocol in CAS Profile
Cyclades-TS Installation & Service Manual
Parameter Description Value for
This Example
all.protocol For the console server profile, the possible protocols are socket_server
(when telnet is used), socket_ssh (when ssh version one or two is used),
raw_data (to exchange data in transparent mode – similar to
socket_server mode, but without telnet negotiation, breaks to serial ports,
etc.), or modbus (an application layer messaging protocol for clent/server
communication widely used for industrial automation).
modbus
all.modbus_smode Communication mode through the serial ports. This parameter is
meaningful only when modbus protocol is configured. The valid options
are ascii (normal TX/RX mode) and rtu (some time constraints are
observed between characteres while transmiting a frame). If not
configured, ASCII mode will be assumed.
ascii
FIGURE I.2 - MODBUS PSLAVE.CONF PORT SPECIFIC PARAMETERS (CONT.)
(ONLY WHERE IT DIFFERS FROM THE STANDARD CAS PROFILE)
Note: The MODBUS port can be configured in the file /etc/services, changing the corresponding line. By default,
the port is 502, as specified in Modbus/TCP draft to the IETF.