Contents
Chapter 1 | Introduction | 1 |
| Hot Standby CPU Redundancy Product | 1 |
| Features of the Hot Standby CPU Redundancy Product | 3 |
| Benefits of the Hot Standby CPU Redundancy Product | 3 |
| I/O Systems for Hot Standby CPU Redundancy Systems | 4 |
| Genius I/O System | 4 |
| LocalI/OSystem | 4 |
| Cable Connections | 4 |
| Control Strategy | 5 |
| Basic Hot Standby Operation | 5 |
| Redundancy CPU Module | 7 |
| Redundancy Communications Module | 7 |
| Bumpless Switching | 8 |
| Synchronized CPUs | 8 |
| Effect on Scan Time | 8 |
| Fail Wait Time | 8 |
| Switch to Backup Unit Time | 8 |
| Configurable Backup Data Size | 9 |
| 9 | |
| 9 | |
| Programming Considerations | 10 |
| Configuration Requirements | 10 |
| Definition of Terms | 11 |
| Commonly Used Acronyms | 12 |
GFK±0827 | Series 90±70 Hot Standby CPU Redundancy User's Guide ± December 1993 |
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