GE IC695PNC001 User Manual page 23

Glossary, continued
Record Data Object. Services used to read and write structured data stored in a
RDO
PROFINET IO-Device.
Along with Send Clock determines the Update Period for a PROFINET cyclic data transfer
Reduction
between two devices (see IOCR). The Update Period equals the Reduction Ratio
Ratio
multiplied by the Send Clock time. For example, if the Reduction Ratio is 4 and the Send
Clock is 1ms, the Update Period is 4ms.
For an RX3i PROFINET network, a Remote Node is any PROFINET IO-Device, such as a
Remote Node
rack of I/O modules with a Remote Scanner or a third party PROFINET IO-Device.
Real-Time Acyclic. A PROFINET-IO Mechanism used to exchange non-periodic data
RTA
such as alarms.
Real-Time Cyclic. A PROFINET-IO Mechanism used to exchange input and output data.
RTC
Value between 1 and 128 inclusive in 31.25 µs units (equivalent to a range of 31.25 µs to
Send Clock
4 ms) used to calculate the Update Period for a PROFINET cyclic data transfer between
two devices (see IOCR). The Send Clock is the basis for all other scheduling parameters.
The time to delay a scheduled PROFINET cyclic data transfer frame. Measured in
Send Offset
nanoseconds from 0 to 3,999,999. Must be less than the Send Clock time.
Small Form-factor Pluggable. Pluggable, hot-swappable transceivers.
SFP
Simple Network Management Protocol. UDP-based network protocol that facilitates the
SNMP
exchange of management information between network devices.
Module status data in RX3i CPU reference memory.
Status Bits
PROFINET-IO representation of the smallest configurable entity of a PROFINET Module.
Submodule
Service Request Function Block. A control system service initiated by the RX3i CPU.
SVC_REQ
In Ethernet, the transmission of a network message to an individual host.
Unicast
The time between PROFINET cyclic data transfers between an IO-Controller and an
Update Period
IO-Device.
GFK-2571A Chapter 1 Introduction
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