NEC switch - Page 12

User’s Manual U12978EJ3V0UD
12
CHAPTER 7 WATCHDOG TIMER ........................................................................................................91
7.1 Watchdog Timer Functions.......................................................................................................91
7.2 Watchdog Timer Configuration ................................................................................................92
7.3 Registers Controlling Watchdog Timer ...................................................................................93
7.4 Watchdog Timer Operation.......................................................................................................95
7.4.1 Operation as watchdog timer........................................................................................................ 95
7.4.2 Operation as interval timer............................................................................................................ 96
CHAPTER 8 USB FUNCTION ...............................................................................................................97
8.1 USB Overview.............................................................................................................................97
8.2 USB Function Features .............................................................................................................98
8.3 USB Function Configuration.....................................................................................................98
8.4 Registers Controlling USB Function......................................................................................109
8.5 USB Function Operation .........................................................................................................122
8.5.1 USB timer operation ................................................................................................................... 122
8.5.2 Remote wakeup control operation .............................................................................................. 125
8.6 Interrupt Request from USB Function ................................................................................... 127
8.6.1 Interrupt sources......................................................................................................................... 127
8.6.2 Cautions when using interrupts .................................................................................................. 129
8.7 USB Function Control..............................................................................................................130
8.7.1 Relationship between packets and operation modes ................................................................. 130
8.7.2 Interrupt servicing flow................................................................................................................ 136
8.8 USB Function Internal Circuit Operations.............................................................................140
8.8.1 Operation of transmit/receive pointer.......................................................................................... 140
8.8.2 Receive bank switching ID detection buffer operation................................................................ 147
8.8.3 Sync detection/USBCLK detector operation............................................................................... 148
8.8.4 NRZI encoder operation ............................................................................................................. 150
8.8.5 Bit stuffing/strip controller operation ........................................................................................... 151
CHAPTER 9 SERIAL INTERFACE 10 ...............................................................................................154
9.1 Functions of Serial Interface 10..............................................................................................154
9.2 Configuration of Serial Interface 10 ....................................................................................... 155
9.3 Register Controlling Serial Interface 10.................................................................................157
9.4 Operation of Serial Interface 10..............................................................................................159
9.4.1 Operation stop mode .................................................................................................................. 159
9.4.2 3-wire serial I/O mode................................................................................................................. 160
CHAPTER 10 REGULATOR ................................................................................................................162
CHAPTER 11 INTERRUPT FUNCTIONS............................................................................................163
11.1 Interrupt Function Types......................................................................................................... 163
11.2 Interrupt Sources and Configuration .....................................................................................163
11.3 Registers Controlling Interrupt Function ..............................................................................166
11.4 Interrupt Servicing Operation .................................................................................................171
11.4.1 Non-maskable interrupt acknowledgment operation .................................................................. 171