I/O Poll Command/Response Messages - ICP DAS USA I-7242D User Manual

I-7242D user manual
3.2.2

I/O Poll Command/Response Messages

The Poll Command Message is a command that is transmitted by the
Master. A Poll Command is directed towards a single, specific Slave
(point-to-point connection). A Master must transmit a separate Poll command
message for each one of its Slaves that will be polled. The Poll Response
Message is an I/O message that the Slave transmits back to the Master when
a Poll Command is received. Within a Slave the two messages are
received/transmitted by a single Connection Object. The architecture is as
figure 3-5.
Figure 3-5 Architecture of IO poll message
I-7242D DeviceNet/Modbus RTU Gateway User's Manual, July 2006, Version 1.1 28/124