Renesas RX Series

10. Clock Frequency Accuracy Measurement Circuit (CAC) ............................................................. 210
10.1 Overview ........................................................................................................................................... 210
10.2 Register Descriptions ......................................................................................................................... 212
10.2.1 CAC Control Register 0 (CACR0) ........................................................................................... 212
10.2.2 CAC Control Register 1 (CACR1) ........................................................................................... 213
10.2.3 CAC Control Register 2 (CACR2) ........................................................................................... 214
10.2.4 CAC Interrupt Request Enable Register (CAICR) ................................................................... 215
10.2.5 CAC Status Register (CASTR) ................................................................................................ 216
10.2.6 CAC Upper-Limit Value Setting Register (CAULVR) ........................................................... 217
10.2.7 CAC Lower-Limit Value Setting Register (CALLVR) ........................................................... 217
10.2.8 CAC Counter Buffer Register (CACNTBR) ............................................................................ 217
10.3 Operation ........................................................................................................................................... 218
10.3.1 Measuring Clock Frequency ..................................................................................................... 218
10.3.2 Digital Filtering of Signals on the CACREF Pin ..................................................................... 219
10.4 Interrupt Requests .............................................................................................................................. 219
10.5 Usage Notes ....................................................................................................................................... 220
10.5.1 Module Stop Function Setting .................................................................................................. 220
11. Low Power Consumption ............................................................................................................. 221
11.1 Overview ........................................................................................................................................... 221
11.2 Register Descriptions ......................................................................................................................... 225
11.2.1 Standby Control Register (SBYCR) ......................................................................................... 225
11.2.2 Module Stop Control Register A (MSTPCRA) ........................................................................ 226
11.2.3 Module Stop Control Register B (MSTPCRB) ........................................................................ 227
11.2.4 Module Stop Control Register C (MSTPCRC) ........................................................................ 229
11.2.5 Module Stop Control Register D (MSTPCRD) ........................................................................ 230
11.2.6 Operating Power Control Register (OPCCR) ........................................................................... 231
11.2.7 Sub Operating Power Control Register (SOPCCR) ................................................................. 232
11.2.8 Sleep Mode Return Clock Source Switching Register (RSTCKCR) ....................................... 237
11.3 Reducing Power Consumption by Switching Clock Signals ............................................................. 239
11.4 Module Stop Function ....................................................................................................................... 239
11.5 Function for Lower Operating Power Consumption ......................................................................... 239
11.5.1 Setting Operating Power Control Mode
................................................................................... 239
11.6 Low Power Consumption Modes ...................................................................................................... 241
11.6.1 Sleep Mode ............................................................................................................................... 241
11.6.1.1 Entry to Sleep Mode ........................................................................................................ 241
11.6.1.2 Exit from Sleep Mode ..................................................................................................... 242
11.6.1.3 Sleep Mode Return Clock Source Switching Function ................................................... 242
11.6.2 Deep Sleep Mode ...................................................................................................................... 243
11.6.2.1 Entry to Deep Sleep Mode .............................................................................................. 243
11.6.2.2 Exit from Deep Sleep Mode ............................................................................................ 244
11.6.3 Software Standby Mode ........................................................................................................... 245