
Table of Contents
(Continued)
Revision 1.2
11
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P
6.2.7
6.2.8
6.2.9
6.2.10
Arbitration on the Bus ................................................................................................120
Packet Error Check (PEC) .........................................................................................120
ACCESS.bus Protocol ...............................................................................................121
Transaction Execution ...............................................................................................125
6.3
ACB REGISTERS (ON ACCESS.BUS ONLY) ........................................................................126
6.3.1
ACB Register Map (on ACCESS.bus Only) ..............................................................126
6.3.2
ACCESS.bus Control/Status Register (ACBCST) .....................................................127
6.3.3
ACCESS.bus Configuration Register (ACBCFG) ......................................................128
6.3.4
ACCESS.bus Lock Control Register (ACBLKCTL) ...................................................128
6.3.5
ACCESS.bus Fast Disable Register (ACBFDIS) .......................................................130
6.3.6
ACCESS.bus TRI-STATE Register (ACBTRIS) ........................................................131
6.3.7
Access Lock Configuration 1 Register (ACCLCF1) ...................................................132
6.3.8
Access Lock Configuration 2 Register (ACCLCF2) ...................................................133
6.4
ACB REGISTER BITMAP ........................................................................................................134
7.0
General-Purpose Input/Output (GPIO) Ports
7.1
OVERVIEW .............................................................................................................................135
7.2
BASIC FUNCTIONALITY ........................................................................................................136
7.2.1
Configuration Options ................................................................................................136
7.2.2
Operation ...................................................................................................................137
7.3
EVENT HANDLING AND SYSTEM NOTIFICATION ..............................................................137
7.3.1
Event Configuration ...................................................................................................137
7.3.2
System Notification ....................................................................................................138
7.4
GPIO PORT REGISTERS .......................................................................................................139
7.4.1
GPIO Pin Configuration Registers Structure .............................................................139
7.4.2
GPIO Port Runtime Register Map .............................................................................140
7.4.3
GPIO Data Out Register (GPDO) ..............................................................................140
7.4.4
GPIO Data In Register (GPDI) ..................................................................................140
7.4.5
GPIO Event Enable Register (GPEVEN) ..................................................................141
7.4.6
GPIO Event Status Register (GPEVST) ....................................................................141
8.0
Real-Time Clock (RTC)
8.1
OVERVIEW .............................................................................................................................142
8.2
FUNCTIONAL DESCRIPTION ................................................................................................142
8.2.1
Bus Interface .............................................................................................................142
8.2.2
RTC Clock Generation ..............................................................................................142
8.2.3
Internal Oscillator .......................................................................................................142
8.2.4
External Oscillator .....................................................................................................143
8.2.5
Timing Generation .....................................................................................................144
8.2.6
Timekeeping ..............................................................................................................144
8.2.7
Updating ....................................................................................................................145
8.2.8
Alarms .......................................................................................................................145
8.2.9
Power Supply ............................................................................................................146
8.2.10
System Bus Lockout ..................................................................................................147