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208
4109J–8051–10/06
AT8xC51SND1C
27. Table of Contents
1
Description ............................................................................................... 2
2
Typical Applications ................................................................................ 2
3
Block Diagram .......................................................................................... 2
4
Pin Description ......................................................................................... 3
4.1 Pinouts ....................................................................................................................3
4.2 Signals .....................................................................................................................5
4.3 Internal Pin Structure .............................................................................................11
5
Clock Controller ..................................................................................... 12
5.1 Oscillator ...............................................................................................................12
5.2 X2 Feature .............................................................................................................12
5.3 PLL ........................................................................................................................13
5.4 Registers ...............................................................................................................15
6
Data Memory .......................................................................................... 25
6.1 Internal Space .......................................................................................................25
6.2 External Space ......................................................................................................26
6.3 Dual Data Pointer ..................................................................................................28
6.4 Registers ...............................................................................................................30
7
Special Function Registers ................................................................... 32
8
Interrupt System .................................................................................... 38
8.1 Interrupt System Priorities .....................................................................................38
8.2 External Interrupts .................................................................................................41
8.3 Registers ...............................................................................................................42
9
Power Management ............................................................................... 47
9.1 Reset .....................................................................................................................47
9.2 Reset Recommendation to Prevent Flash Corruption ...........................................48
9.3 Idle Mode ...............................................................................................................49
9.4 Power-down Mode ................................................................................................49
9.5 Registers ...............................................................................................................51
10
Timers/Counters .................................................................................... 52
10.1 Timer/Counter Operations ...................................................................................52
10.2 Timer Clock Controller .........................................................................................52