SMART I/O User’s Manual | Chapter 2 | |||
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A complete list of the operate COMMANDS may be obtained by selecting a project from the ISaGRAF projects group, opening an application and observing the Common defines in the Dictionary
O_INIT_CODE : The syntax and usage have already been explained.
O_POWERFAIL_SET : The purpose of this operate call is to detect when (if) the power to the PLC (SMART I/O) has failed. The function is normally built into the initialization stage of an application and has the following syntax :
RetVar := OPERATE(s_time, O_POWERFAIL_SET, 0);
When the application is initialized, the start time is recorded in battery backed ram (1) at the given address (s_time). If the power to the PLC fails (2) and recovers at a later stage (3), the software makes a comparison with the actual clock time (via the RTC) and the time stored in this memory location. If a discrepancy exists then the RetVar will record this fact. Refer to the PEP online help for more information pertaining to the implementation of this operate call.
1 | 2 | 3 |
Voltage |
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Page | 2 - 34 | ©1996 PEP Modular Computers GmbH | March 12, 1996 |
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