Allen-Bradley PLC-5 User Manual page 10

Table of Contents 6
Preparing Power-Up Routines
Preparing Fault Routines
Publication 1785-UM012D-EN-P - July 2005
Step 2 - Use the Programming Software to Enter
or Edit the Data You Want to Force in the Extended Force
Configuration Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-7
Step 3 - Use the Programming Software to Enter
Force Values for the Specified Data Table Files . . . . . . . . . . . . 13-8
Step 4 - Enable or Disable the Forces . . . . . . . . . . . . . . . . . . . . 13-8
Using Extended Forcing with Time-Critical Applications. . . . . 13-8
Using Special Programming Routines . . . . . . . . . . . . . . . . . . . . . . . 13-10
Priority Scheduling for Interrupts and MCPs . . . . . . . . . . . . . . . . . 13-11
Program Execution States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-12
Influencing Priority Scheduling. . . . . . . . . . . . . . . . . . . . . . . . . 13-14
Defining and Programming Interrupt Routines . . . . . . . . . . . . . . . 13-15
Chapter 14
Using This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-1
Setting Power-Up Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-1
Allowing or Inhibiting Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-2
Defining a Controller Power-Up Procedure. . . . . . . . . . . . . . . . . . . 14-2
Chapter 15
Using This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-1
Understanding the Fault Routine Concept . . . . . . . . . . . . . . . . . . . . 15-1
Responses to a Major Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-1
Understanding Controller-Detected Major Faults . . . . . . . . . . . . . . 15-2
Fault in a Controller-Resident or Extended-Local I/O Rack . . 15-3
Fault in a Remote I/O Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . 15-3
Defining a Fault Routine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-4
Defining a Watchdog Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-5
Avoiding Multiple Watchdog Faults . . . . . . . . . . . . . . . . . . . . . . 15-6
Programming a Fault Routine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-6
Setting an Alarm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-7
Clearing a Major Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-7
Changing the Fault Routine from Ladder Logic . . . . . . . . . . . . 15-9
Using Ladder Logic to Recover from a Fault. . . . . . . . . . . . . . 15-10
Block-Transfers in Fault Routines . . . . . . . . . . . . . . . . . . . . . . 15-11
Testing a Fault Routine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-11
Monitoring Faults. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-11
Monitoring Major/Minor Faults and Fault Codes . . . . . . . . . . 15-12
Interpreting Major Faults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-12
Interpreting Minor Faults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-12
Monitoring Status Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-13