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31GFK–0644 Chapter 4 Programming Guide
If the module is a master, this bit resets or stops both the module and the I/O Link. If
the module is a slave, setting this bit to 1 resets or stops only the module itself, not the
I/O Link.
Disable or Enable the Input Update (bit 10)
To disable the input update portion of the I/O scan, write a 1 to control bit 10. This might
be done during program debugging, or if the program uses multiple calls to the
LINKxxX Program Block. Disabling the input update causes the module to ignore new
inputs it receives. To re–enable input updates, clear control bit 10 by writing a 0 to it.
Remember that input data is considered to be output data by the device that sends it
(see page 26 for an explanation of input and output data).
If the module is a master, setting this bit to 1 causes all input references assigned to
devices on the link to hold their last states. The slaves continue to send data to the
master, but the new data is ignored by the master; no data is written to the input table.
If the module is a slave, setting this bit to 1 causes the input references assigned to the
module to hold their last states. The master continues to send data to the slave, but the
new data is ignored by the slave. No data is written to the input table.
Disable or Enable the Output Update (bit 9)
Disabling the output update keeps the module from updating outputs; it does not keep
the module from sending them. If outputs are disabled, the module keeps sending its last
set of output data repeatedly. This might be desirable during program debugging, or if
the program uses multiple calls to the Program Block.
Remember that output data is considered to be input data by the device that receives it.
To disable the output update, write a 1 to control bit 9. To re–enable output updates,
clear control bit 9 by writing a 0 to it.
If the module is a master, disabling the output update means that no new data will be
sent to any slaves on the link. They will continue to receive the same set of data from
the master repeatedly.
If the module is a slave, disabling the output update means that no new data will be sent
to the master. It will continue to receive the same set of data from that specific slave
repeatedly.