Advantech PCI-1758 Series, Руководство пользователя

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3 PCI-1758 Series User Manual
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Board ID Setting
The PCI-1758 series has a built-in DIP switch that defines each card’s ID when multi -
ple cards have been installed in the same PC chassis. The board ID setting function
is very useful when users build systems with multiple PCI-1758 series cards. With
correct Board ID settings, you can easily identify and access each card during hard -
ware configuration and software programming.
Watchdog Timer Function
The watchdog timer is a software-configurable feature used to set critical outputs to
safe states in the event of a software failure. It will activate if there is a loss of com -
munication between the application and the PCI-1758U card. If the PCI-1758U card
does not receive a watchdog clear software command within the interval time speci -
fied for the watchdog timer, the outputs go to a user-defined safe state and remain in
that state until the watchdog timer is disabled and new values are written by the soft -
ware.
After the watchdog timer expires, the PCI-1758U card ignores any writes until the
watchdog timer is disabled. Users can set the watchdog timer timeout period through
WDT register to specify the amount of time that must elapse before the watchdog
timer expires. The counter on the watchdog timer is configurable up to (232-1) x 100
ns (approximately seven minutes) before it expires.
Reset Protection
When the system has undergone a hot reset (i.e., without turning off the system
power), the PCI-1758 series can either retain output values of each channel, or
return to its default configuration as open status, depending on its on-board jumper
setting. This function protects the system from incorrect operations during unex -
pected system resets.
All the above features make PCI-1758 series cards ideal for industrial applications.
1.3 Applications

Industrial ON/OFF control

Switch status sensing

BCD interfacing

Digital I/O control

Industrial and lab automation
Note! For detailed specifications of the PCI-1758 series cards, please refer to
Appendix A.