RF096-35/55-100 [Revision 1.0.0] 12.12.2018
Pipe ID Control System. RF096-35/55-100 Series
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12. Communication
12.1. Communication sequence
The I-7580 module basically contains 4 buffers:
·
PROFINET IO device input buffer.
·
PROFINET IO device output buffer.
·
COM port input buffer.
·
COM port output buffer.
The PROFINET IO controller basically contains 2 buffers:
·
PROFINET IO controller input buffer.
·
PROFINET IO controller output buffer.
In the I-7580 module, data is transferred from the COM port input buffer to the
PROFINET IO device output buffer, and from the PROFINET IO device input buffer to the
COM port output buffer. The data flow is illustrated below.
During each message cycle, the PROFINET IO controller writes the content of its
output buffer to the PROFINET IO device input buffer and reads the content of the
PROFINET IO device output buffer to its input buffer. The exchange cycle is taking place
even though the content of the PROFINET IO controller and PROFINET IO device output
buffer has not changed. The data flow between the PROFINET IO controller and the I-7580
module is shown below.
