RUN/STOP Switch Operation ...................................................................................................................................... 152

4.6

Flash Memory Operation ................................................................................................. 153

4.7

Logic/Configuration Source and CPU Operating Mode at Power-Up ........................ 154

4.7.1

CPU Mode when Memory Not Preserved/Power-up Source is Flash ....................................................... 155

4.7.2

CPU Mode when Memory Preserved ....................................................................................................................... 156

4.8

Clocks and Timers ............................................................................................................ 157

4.8.1

Elapsed Time Clock .......................................................................................................................................................... 157

4.8.2

Time-of-Day Clock ............................................................................................................................................................ 158

4.8.3

Watchdog Timer ................................................................................................................................................................ 159

4.9

System Security ................................................................................................................ 161

4.9.1

Passwords and Privilege Levels - Legacy Mode .................................................................................................. 162

4.9.2

OEM Protection - Legacy Mode ................................................................................................................................. 164

4.9.3

Enhanced Security for Passwords and OEM Protection ................................................................................. 165

4.9.4

Legacy/Enhanced Security Comparison................................................................................................................. 166

4.10

PACSystems I/O System .................................................................................................. 167

4.10.1

I/O Configuration ............................................................................................................................................................... 168

4.10.2

Genius I/O ............................................................................................................................................................................. 170

4.10.3

I/O System Diagnostic Data Collection ................................................................................................................... 172

4.11

Power-Up and Power-Down Sequences ....................................................................... 174

4.11.1

Power-Up Sequence ........................................................................................................................................................ 174

4.11.2

Power-Down Sequence.................................................................................................................................................. 175

4.11.3

Power Cycle Operation with an Energy Pack....................................................................................................... 176

4.11.4

Retention of Data Memory Across Power Failure ............................................................................................. 179

Chapter 5

Communications ........................................................................................................ 181

5.1

Ethernet Communications .............................................................................................. 182

5.1.1

Embedded Ethernet Interface .................................................................................................................................... 182

5.1.2

Ethernet Interface Modules ......................................................................................................................................... 187

5.2

Serial Communications ................................................................................................... 188

5.2.1

Serial Port Communications Capabilities .............................................................................................................. 188

5.2.2

Configurable STOP Mode Protocols ......................................................................................................................... 190

5.2.3

Serial Port Pin Assignments ......................................................................................................................................... 191

5.2.4

Serial Port Electrical Isolation ..................................................................................................................................... 195

5.2.5

Serial Cable Lengths and Shielding .......................................................................................................................... 196

5.2.6

Serial Port Baud Rates .................................................................................................................................................... 197

5.3

Series 90-70 Communications and Intelligent Option Modules ............................... 198

5.3.1

Communications Coprocessor Module (CMM) ................................................................................................... 198

5.3.2

Programmable Coprocessor Module (PCM) ......................................................................................................... 199

5.3.3

DLAN/DLAN+ (Drives Local Area Network) Interface ...................................................................................... 200

GFK-2222AD

April 2018

Contents

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