National Instruments NI CVS-1450 Series - Manual (Page 58)

Chapter 4 Digital I/O Functionality
NI CVS-1450 Series User Manual 4-10 ni.com
Shutdown
Shutdown mode is a software-enabled feature, that when activated, allows
an external device to halt the CVS-1450 device processing operations.
Additionally, Shutdown mode allows you to specify user-defined
shutdown states for all fault conditions.
When Shutdown mode is enabled and the shutdown input signal,
ISO Input 11, turns off, the CVS-1450 device registers an external
shutdown condition. When this fault occurs, the POWER OK LED turns
red and all system operation halts. To resume operation, you must reset the
CVS-1450 device.
For all fault conditions, outputs operate according to user-defined
shutdown states. Each TTL output is configurable to drive high, drive low,
or 3-state, and each isolated output is on/off configurable.
Shutdown mode is unavailable when the SAFE MODE DIP switch is
turned on.
Refer to Table 4-4 for a summary of how user configuration affects the
shutdown condition.
Disabling Shutdown Mode
To disable Shutdown mode once it is enabled, remove Shutdown mode
from the software script and reset the CVS-1450 device. To reset the
system, press the RESET button on the CVS-1450 device front panel for
at least two seconds.
Note For prototyping when equipment is unavailable, you can wire from Viso to
ISO Input 11 to simulate external equipment that indicates to the CVS-1450 device to
operate normally.
Watchdog Timer
The watchdog timer is a software configurable feature that can monitor
software on the CVS-1450 device and take action if the software is
unresponsive. The millisecond counter on the watchdog timer is
configurable up to 65,534 ms, in 1 ms increments, before it expires.