PTC Sigma Tile V5, Руководство пользователя

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STEP 5 – UNDERSTANDING THE SIGMA TILE PYTHON SCRIPT
The heart of the Sigma Tile is the
SigmaTile_SenseHat_V5.py Python script which can be
found in the ThingWorx Developer Portal . This script reads the Sense Hat sensors and
uses the MODBUS protocol to communicate between Raspberry Pi and Kepware.
Modbus is a serial communication protocol developed in 1979 for use in Programmable
Logic Controllers (PLCs). You can find the details about this protocol at
modbus.org .
Raspberry Pi will act as the server and Kepware will be a client. The python scripts will
simply initialize the Modbus server and update the values from the Sense HAT when it
receives the request from the client. We use pymodbus libraries, the details of which
can be found at
https://github.com/bashwork/pymodbus . Other libraries and protocols
are available which are not in the scope of this documentation.
Other aspects of the code include the reading of the Sense HAT’s joystick position to
trigger various events: change of the LED Display mode and change of the Error Code
values as illustrated in the picture below:
For more details on the functional aspect of the Sigma Tile python script, please refer to
the Learn KepServerEX Using a Sigma Tile guide and the Learn ThingWorx
Manufacturing Apps Using a Sigma Tile guide.
STEP 6 - CREATING MICRO-SD CARD WITH SIGMA TILE SOFTWARE