1-2 Series 90-30/20/Micro Programmable Controllers Reference Manual September 1998 GFK-0467K
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an alert, such as a low battery signal to indicate that the voltage of the battery protecting the
memory is low and should be replaced. The condition or failure is called a fault.
Faults are handled by a software a lar m processor function that record s the faults in either the PLC
fault table or the I/O fault table. (The Model 331 and Model 340/341 CPUs also time-stamp the
faults.) These tables can be displayed through the programming software on the PLC Fault Table
and I/O Fault Table screens in Logicmaster 90-30/20/Micro software using the control and status
functions.
Additional Reference Information:See the appendices in the b ack of this manual.
Appendix A lists the memory size in b ytes a nd the execution time in microsecon ds for each
programming in struction.
Appendix B describes how to interpret the message structure format when reading the PLC and I/O
fault tables.
Appendix C lists the instruction mnemonics used with Logicmaster 90-30/20/Micro software.
Appendix D lists the special keyboard assignments used with Logicmaster 90-30/20/Micro
software.
Appendix E provides special considerations and instructions for using floating-point math
(available only on the 350 and 360 series of 90-30 CPUs).