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communication protocol, the time required for data update can be quite
different and read data is not immediately available at activation of coil, but
only after a certain time depending from communication delays.
Instructions COM and EXP require the configuration of following
parameters:
• Index (max. 16 different serial pollings)
• Type of operation:
• Reading: PL260 will read continuously data from slave device and will
store them in an internal memory area
• Writing: PL260 will write continuously data on an internal memory area
of the slave device
• Reading/Writing: PL260 will read data on slave device and will store
them in an internal memory area; when these internal data on PL260
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 PL260 where data must be read/written
• Word number (the same reading / writing instruction can work
simultaneously on more consecutive data
“NAIS MATSUSHITA-MASTER” PROTOCOL
This communication protocol allows to read/write data (bit or word) on a
Nais - Matsushita plc. Generally, communication interface is a RS232 and
communication format is 9600,8,O,1.
The following tables show all elements which can be read/written by the
plc. The address bit or word to be read/write is obtained adding the real
bit/word address (between Min and Max) to the value showed in the Offset
column. Each instruction "COM" or "EXP" can execute reading/writing for
each type of data which is indicated in the column "Max number of
consecutive bid/word read/wrote".