TABLE OF CONTENTS
FEATURES............................................................................................................................................ 1
GENERAL DESCRIPTION .................................................................................................................... 2
PIN CONFIGURATION .......................................................................................................................... 5
DESCRIPTION OF PIN FUNCTIONS .................................................................................................... 6
PROTOCOL DESCRIPTION ................................................................................................................. 9
NETWORK PROTOCOL ................................................................................................................... 9
DATA RATES .................................................................................................................................... 9
NETWORK RECONFIGURATION .................................................................................................. 10
BROADCAST MESSAGES ............................................................................................................. 11
EXTENDED TIMEOUT FUNCTION................................................................................................. 11
LINE PROTOCOL ........................................................................................................................... 11
SYSTEM DESCRIPTION ..................................................................................................................... 14
MICROCONTROLLER INTERFACE ............................................................................................... 14
TRANSMISSION MEDIA INTERFACE............................................................................................ 23
FUNCTIONAL DESCRIPTION............................................................................................................. 28
MICROSEQUENCER ...................................................................................................................... 28
INTERNAL REGISTERS ................................................................................................................. 31
INTERNAL RAM.............................................................................................................................. 49
COMMAND CHAINING ................................................................................................................... 54
INITIALIZATION SEQUENCE ......................................................................................................... 56
IMPROVED DIAGNOSTICS............................................................................................................ 57
OPERATIONAL DESCRIPTION.......................................................................................................... 59
MAXIMUM GUARANTEED RATINGS* ........................................................................................... 59
DC ELECTRICAL CHARACTERISTICS.......................................................................................... 59
TIMING DIAGRAMS ............................................................................................................................ 62
APPENDIX A ....................................................................................................................................... 82
APPENDIX B: EXAMPLE OF INTERFACE CIRCUIT DIAGRAM TO ISA BUS................................. 86
COM20022, FUNCTIONAL REV. B ANOMALY.................................................................................. 87
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