State Industries GFK-0827 manual Chapter Operation System Operation

Contents

Chapter 4	Operation	55
	Section 1: System Operation	55
	Power-Up Sequence of a Redundant CPU	55
	Incompatible Configurations	56
	Resynchronization of the Redundant CPU	57
	Hot-Standby Redundancy Control Strategy	58
	Synchronous Scan	59
	First Data Transfer %I, %AI and Synchronization	59
	Data Transfer from Backup Unit to Active Unit	60
	Second Data Transfer %Q, %AQ, %R, and %M	61
	Switching Control to Backup Unit	61
	Role Switch SVCREQ	62
	%S References for CPU Redundancy	63
	Redundancy CPU Considerations	64
	Features not Available with CPU 780	64
	I/OInterrupts	64
	Timed Interrupts	64
	VME Integrator Racks	64
	STOP/IOSCAN Mode	64
	Flash Operation	64
	Differences in Operation for CPU 780	65
	RUN Disabled Mode	65
	Configuration of Fault Actions	67
	STOP to RUN Mode Transition	68
	Background Window Time	68
	Background User Checksum and Background Window
	Timing Instructions	69
	Miscellaneous Operation Information	70
	Timer and PID Function Blocks	70
	Timed Contacts	70
	OVR_PRE %S Reference	70
	Genius Bus Controller Switching	71

GFK±0827 Series 90±70 Hot Standby CPU Redundancy User's Guide ± December 1993

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