Thermo Scientific Micro-Tech 9101, Справочное руководство

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C-70 Micro-Tech 9101/9201 Reference Manual, Rev J Thermo Fisher Scientific
The PROFIBUS interface allows a remote intelligent device to read and
write data from and to the Micro-Tech.
During the communication activity, the Micro-Tech will always act as a
slave, meaning it will respond to a request from a master device on the
line, but will never attempt to send messages out.
The Micro-Tech updates almost all its basic variables (e.g.; load, weight,
rate, totals) every 100 milliseconds. With the same frequency the
Micro-Tech updates the read buffer. If the master performs more
communications in this period, it will receive the same data more times.
The write request is interpreted by the Micro-Tech in polling with a
period of 100 milliseconds.
Errors in the communication are managed in the Micro-Tech.
A specific alarm is generated whenever one or both of the following
conditions become true:
•
The SPC3 controller installed on the PROFIBUS board does not
recognize successful data transfer within the watch dog control
interval.
•
The received data contains errors (value overlaps limits, register
number does not exist, group number does not exist); in this case
the Micro-Tech activates an
Expanded Diagnostics request to the
master. Details of this diagnostic can be found at DIAGNOSTIC
DATA paragraph.
Details on how to define and manage the generated alarm can be found
in starting on B-42.
Data are organized in registers collected in several block, some of them are
“Read only” (RO) while others are “Write Only” (WO) block. Blocks are
identified by a number as below:
Communication
Timings
Error Management
Data
Organization