Rockwell Automation 1770, D17706.5.16 Ref Mnl DF1 Protocol Command - Manual (Page 5)

Table of Contents
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Using HalfĆduplex Protocols to Send and
Receive Messages 3-1 . . . . . . . . . . . . . . . . . . . . . . .
HalfĆduplex Protocol Message Transmission 3-2 . . . . . . . . . . . .
Transmitter and Receiver Message Transfer 3-3 . . . . . . . . . . . .
HalfĆduplex Protocol Environment 3-3 . . . . . . . . . . . . . . . . . . . .
Message Characteristics 3-7 . . . . . . . . . . . . . . . . . . . . . . . . . .
Master Polling Responsibilities 3-7 . . . . . . . . . . . . . . . . . . . . . .
Duplicate Detection 3-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inactive Slave Polling 3-7 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Full Sinks 3-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Simplified Network Layer 3-8 . . . . . . . . . . . . . . . . . . . . . . . .
Slave Transceiver Actions 3-9 . . . . . . . . . . . . . . . . . . . . . . . . . .
HalfĆDuplex Protocol Diagrams 3-11 . . . . . . . . . . . . . . . . . . . . . .
Normal Message Transfer 3-12 . . . . . . . . . . . . . . . . . . . . . . . .
Message Transfer with Invalid BCC/CRC 3-12 . . . . . . . . . . . . .
Message Transfer with ACK Destroyed 3-13 . . . . . . . . . . . . . .
Poll with No Message Available 3-13 . . . . . . . . . . . . . . . . . . . .
Poll with Message Returned 3-14 . . . . . . . . . . . . . . . . . . . . . .
Duplicate Message Transmission 3-15 . . . . . . . . . . . . . . . . . .
Message Sink Full, Case 1 3-16 . . . . . . . . . . . . . . . . . . . . . . .
Message Sink Full, Case 2 3-17 . . . . . . . . . . . . . . . . . . . . . . .
Using FullĆduplex Protocol to Send and
Receive Messages 4-1 . . . . . . . . . . . . . . . . . . . . . . .
FullĆduplex Protocol Message Transmission 4-2 . . . . . . . . . . . . .
FullĆduplex Protocol Environment 4-3 . . . . . . . . . . . . . . . . . . . .
Message Characteristics 4-4 . . . . . . . . . . . . . . . . . . . . . . . . . .
Transmitter and Receiver Message Transfer 4-4 . . . . . . . . . . . .
How the Transmitter Operates 4-5 . . . . . . . . . . . . . . . . . . . . .
How the Receiver Operates 4-7 . . . . . . . . . . . . . . . . . . . . . .
FullĆduplex Protocol Diagrams 4-10 . . . . . . . . . . . . . . . . . . . . . . .
Normal Message Transfer 4-10 . . . . . . . . . . . . . . . . . . . . . . . .
Message Transfer with NAK 4-11 . . . . . . . . . . . . . . . . . . . . . .
Message Transfer with Timeout and ENQ 4-12 . . . . . . . . . . . . .
Message Transfer with ReĆTransmission 4-13 . . . . . . . . . . . . .
Message Transfer with Message Sink Full 4-14 . . . . . . . . . . . .
Message Transfer with NAK on Reply 4-15 . . . . . . . . . . . . . . .
Message Transfer with Timeout and ENQ for the Reply 4-16 . . .
Message Transfer with Message Source Full on the Reply 4-17 .