Datasheet
Rev. 3.00 Mar. 15, 2006 Page xiii of xxxii 
9.9  Port B................................................................................................................................ 145 
9.9.1  Port Data Register B (PDRB) ........................................................................... 145 
Section 10 Realtime Clock (RTC).....................................................................147 
10.1  Features............................................................................................................................. 147 
10.2  Input/Output Pin ............................................................................................................... 148 
10.3  Register Descriptions........................................................................................................ 148 
10.3.1  Second Data Register/Free Running Counter Data Register (RSECDR) ......... 149 
10.3.2  Minute Data Register (RMINDR)..................................................................... 150 
10.3.3  Hour Data Register (RHRDR).......................................................................... 151 
10.3.4  Day-of-Week Data Register (RWKDR) ........................................................... 152 
10.3.5  RTC Control Register 1 (RTCCR1).................................................................. 153 
10.3.6  RTC Control Register 2 (RTCCR2).................................................................. 155 
10.3.7  Clock Source Select Register (RTCCSR)......................................................... 156 
10.4  Operation .......................................................................................................................... 157 
10.4.1  Initial Settings of Registers after Power-On ..................................................... 157 
10.4.2  Initial Setting Procedure ...................................................................................157 
10.4.3  Data Reading Procedure ...................................................................................158 
10.5  Interrupt Sources...............................................................................................................159 
Section 11 Timer B1..........................................................................................161 
11.1  Features............................................................................................................................. 161 
11.2  Input/Output Pin ............................................................................................................... 161 
11.3  Register Descriptions........................................................................................................ 162 
11.3.1  Timer Mode Register B1 (TMB1) .................................................................... 162 
11.3.2  Timer Counter B1 (TCB1)................................................................................ 163 
11.3.3  Timer Load Register B1 (TLB1) ...................................................................... 163 
11.4  Operation .......................................................................................................................... 163 
11.4.1  Interval Timer Operation .................................................................................. 163 
11.4.2  Auto-Reload Timer Operation.......................................................................... 164 
11.4.3  Event Counter Operation .................................................................................. 164 
11.5  Timer B1 Operating Modes .............................................................................................. 164 
Section 12 Timer V............................................................................................165 
12.1  Features............................................................................................................................. 165 
12.2  Input/Output Pins.............................................................................................................. 167 
12.3  Register Descriptions........................................................................................................ 167 
12.3.1  Timer Counter V (TCNTV).............................................................................. 167 
12.3.2  Time Constant Registers A, B (TCORA, TCORB) .......................................... 168 
12.3.3  Timer Control Register V0 (TCRV0) ............................................................... 169 










