Ormec SMLC 160, Installation & Operation Manual

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ServoWire Motion & Logic Controller Manual System Operation
Power ‐ up
ServoWire Motion & Logic Controller is a user ‐ programmable device and operation is dependent on the
ServoWire Pro configuration file & SMLC program present on the System Card.
Whenever AC power is applied to the SMLC, it executes its power ‐ up sequence, which can last up to 30
seconds. When the Watchdog OK LED starts flashing at its once per second rate the power ‐ up sequence
is complete.
NOTE: While the SMLC is booting, the Watchdog, User and System LEDs are lit.
SMLC Non ‐ volatile memory
The CoDeSys Programming language supports non ‐ volatile (NV) variables through the use of RETAIN and
PERSISTENT keywords. Unlike normal CoDeSys variables, NV variable values are maintained through a
loss of power or system reset, and are available to a user's application program when power is restored.
32 Kbytes of NV storage is available on the SMLC Models covered in this manual (minus 256 bytes
reserved for unit information).
Retain variables are identified by the keyword RETAIN . These variables maintain their value even after
an uncontrolled shutdown of the controller as well as after a normal switch off and on of the controller.
When the program is run again, the stored values will be processed further.
Persistent variables are identified by the keyword PERSISTENT . Unlike Retain variables, these variables
retain their value after a re ‐ download or 'Online' 'Reset, but not at switching off and on of the controller
(i.e. not at the command 'Online' 'Reset'), because they are not saved in the "retain area".
To reset the non ‐ volatile variables to 0, use the command ‘Online’ ‘Reset (original)’. Note that this will delete your
boot project as well.
See: CoDeSys Help for further details.
26 SMLC ‐ 004a