Lika CANopen SFA-10000-CB, Руководство пользователя

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Error control message The CANopen error control messages are mapped to a single
1-byte CAN data frame assigned with a fixed identifier that is
derived from the device's Node ID. It is transmitted as boot-up
message before entering
Pre-operational
state after
initialization, and it is transmitted if remotely requested by the
NMT Master (node guarding) or periodically by the device
(heart-beat).
Event driven Event driven messages are transmitted when a defined event
occurs in the node. This may be a change of input states,
elapsing of a local timer, or any other local event.
Event timer The event timer is assigned in CANopen to one PDO. It defines
the frequency of transmission.
Expedited SDO This is a confirmed communication service of CANopen (peer-
to-peer). It is made up by one SDO initiate message of the
Client node and the corresponding confirmation message of
the Server node. Expedited SDOs are used if not more than 4
byte of data has to be transmitted.
Flying Master In safety-critical applications, it may be required that a
missing NMT Master is substituted automatically by another
stand-by NMT Master. This concept of redundancy is called
Flying Master.
Form error A corruption of one of the pre-defined recessive bits (CRC
delimiter, ACK delimiter and EOF) is regarded as a form error
condition that will cause the transmission of an error frame in
the very next bit-time.
Function code First four bits of the CAN identifier in the CANopen pre-
defined identifier set indicating the function of the
communication object (e.g. TPDO_1 or Error Control message).
Galvanic isolation Galvanic isolation in CAN networks is performed by
optocouplers or transformers placed between CAN controller
and CAN transceiver chip.
Gateway Device with at least two network interfaces transforming all
seven OSI (open system interconnection) protocol layers, e.g.
CANopen-to-Ethernet gateway.
Heartbeat CANopen uses heartbeat message to indicate that a node is
still alive. This message is transmitted periodically.
Heartbeat consumer time The heartbeat consumer time defines the time when a node is
regarded as no longer alive due to a missing heartbeat
message.
Heartbeat producer time The heartbeat producer time defines the transmission
frequency of a heartbeat message.
Identifier In general, the term identifier refers to a CAN message
identifier. The CAN message identifier identifies the content of
a data frame. The identifier of a remote frame corresponds to
the identifier of the requested data frame. The identifier
includes implicitly the priority for the bus arbitration.