ATmega640/1280/1281/2560/2561
14.2
14.3
14.4
Reset and Interrupt Vector placement ...........................................................106
Moving Interrupts Between Application and Boot Section .............................109
Register Description ......................................................................................110
15 External Interrupts ............................................................................... 112
15.1
15.2
Pin Change Interrupt Timing ..........................................................................112
Register Description ......................................................................................113
16 8-bit Timer/Counter0 with PWM .......................................................... 118
16.1
16.2
16.3
16.4
16.5
16.6
16.7
16.8
16.9
Features ........................................................................................................118
Overview ........................................................................................................118
Timer/Counter Clock Sources .......................................................................119
Counter Unit ..................................................................................................119
Output Compare Unit .....................................................................................120
Compare Match Output Unit ..........................................................................122
Modes of Operation .......................................................................................123
Timer/Counter Timing Diagrams ...................................................................127
Register Description ......................................................................................129
17 16-bit Timer/Counter (Timer/Counter 1, 3, 4, and 5) .......................... 136
17.1
17.2
17.3
17.4
17.5
17.6
17.7
17.8
17.9
Features ........................................................................................................136
Overview ........................................................................................................136
Accessing 16-bit Registers ............................................................................138
Timer/Counter Clock Sources .......................................................................141
Counter Unit ..................................................................................................142
Input Capture Unit .........................................................................................143
Output Compare Units ...................................................................................145
Compare Match Output Unit ..........................................................................147
Modes of Operation .......................................................................................148
17.10 Timer/Counter Timing Diagrams ...................................................................156
17.11 Register Description ......................................................................................158
18 Timer/Counter 0, 1, 3, 4, and 5 Prescaler ........................................... 170
18.1
18.2
18.3
18.4
Internal Clock Source ....................................................................................170
Prescaler Reset .............................................................................................170
External Clock Source ...................................................................................170
Register Description ......................................................................................171
19 Output Compare Modulator (OCM1C0A) ........................................... 173
iii
2549L–AVR–08/07
ATMEL [ ATMEL ]
