ICP DAS USA I-7188XA, User Manual

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I-7188XA Series User’s Manual ( Ver1.2, Feb/2014, 7MH-019-10 ) ---
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RS-485
7000 series module
RS-485
I-7188XA(D)
(address-1)
RS-485 RS-485
I-7188XA(D)
(address-n)
7000 series module
7000 series module 7000 series module
5.2 Local Real Time Controller (RTC)
In this configuration, the 7000 series modules act as slave devices. The
control programs are implemented in the Host PC. The operation steps
are as follows:

The PC sends commands to the 7000 series modules and
receives some input data.

The PC analyzes this input data and generates some output data

The PC sends commands to the 7000 series modules as output
data
If there are hundreds of 7000 series modules, it will take the Host PC a
long time to analyze and control these modules, so the control program
can be implemented in a local I-7188XA(D). The PC then only has to
send control arguments to the I-7188XA(D), and the I-7188XA(D) will
control the local 7000 series modules based on these control arguments.
In this way, thousands of 7000 series modules can be controlled by the
PC via the I-7188XA(D).
Some control functions are timing-critical, so the local I-7188XA(D) can
handle these functions in real time without the need for control by Host
PC.
7520
Host PC
RS-232
RS-485