Pixsys EPL101, Руководство пользователя

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selected for the relevant serial port. A Master protocol means a protocol
which enables PLC to control the serial line communication, controlling the
data flow towards slave devices. Instruction COM operates with interface
RS485, allowing to connect more devices on the same line. Instructions are
active until the relevant coil is active. Consider also that, according to
communication protocol, the time required for data upgrade can be quite
different and read data are not immediately available at activation of coil,
but only after a certain time depending from communication delays.
Instruction COM requires the configuration of following parameters:
•
Index (max. 16 different serial pollings)
•
Type of operation:
•
Reading: PLC will read continuously data from slave device and will
store them in an internal memory area
•
Writing: PLC will write continuosly data on an internal memory area of
the slave device
•
Reading/Writing: PLC will read data on slave device and will store them
in an internal memory area; when these internal data on PLC will be
modified by the program, any change will be automatically sent also to
slave device by means of a writing instruction (this instruction can work
only on a single data each time).
•
Slave number (communication address of slave device)
•
Data type (word or bit)
•
Number of data (or starting number in case of more data)
•
Internal memory area of PLC where data must be read/written
•
Word number (the same reading / writing instruction can work
simoultaneously on more consecutive data
2.2.22 Protocol for REMOTE CONTROLLER on IR PORT
The protocol for management of data on infrared port (for data received
from remote switch) is checking that data on RX buffer are correct. After
correct receipt of data from remote control, it notices new data to special
marker SM85Il.
Remote controller sends two strings: one for ON/OFF of the plant and one
for the programming. Bit SM85.1 is set to 1 anytime that data are correctly
received on serial port IR. Bit SM85.0 is set to 1 anytime that data are
correctly received and with same address of the machine which received it.
Lenght of sdata strings sent by Remote controller is always 8 byte. First
byte (0xAA) is a symchronous character (start od string) , second byte is
the address of Slave (with offset 100). Additional 4 data byte follow, and
finally 2 byte are added by the checksum. The 4 data byte are all set to
0x65 in case of on-off, or they contain the value to program (still with