Introduction
The OUT_IN_MBUS function is used to emulate a Modbus master
communication from a serial link configured in character mode.
Combined with the possibility of passing a Modbus slave configuration
on the fly to a configuration in character mode via the function WRITE_CMD, this function allows the PLC to operate either
as master or as Modbus slave on the same link.
NOTE: This function is only useful when the two modes Modbus master and
slave are operating concurrently. If this is not the case, the EF
standards
READ_VAR and WRITE_VAR are recommended for managing the Modbus master function (Modbus
slave is implicitly managed by the system). In this case see the Modbus
documentation.NOTE: Be careful that two masters
(on the same bus) do not send requests simultaneously otherwise the
requests are lost and each report will have a bad result which could
be 16#0100 (request could not be processed) or 16#ODFF (slave is not
present).
| WARNING | |
|---|---|
UNEXPECTED APPLICATION BEHAVIOR - WRITING VARIABLES
TO SLAVES Before writing variables from a master to a slave ensure
that the resulting application behavior remains acceptable. Failure to follow these instructions can result in death, serious injury, or equipment damage. | |