Choose By_cpum in INT_16K_RC in Code Option, how to set WTCKS, WDRST, WDRATE bit properly?
When
Code Option choose By_cpum in INT_16K_RC, set different WTCKS, WDRST, WDRATE values,
Watchdog overflow time will be different, the specific form is as follows:
| Watchdog timer overflow time table: | |||
| WTCKS | WTRATE | CLKMD | Watchdog timer overflow time |
| 0 | 0 | 0 | 1 / ( fcpu ÷ ÷16 ) = 293 ms ， Fosc=3.58MHz |
| 0 | 1 | 0 | 1 / ( fcpu ÷  ÷ 16 ) = 500 ms ， Fosc=32768Hz |
| 0 | 0 | 1 | 1 / ( fcpu ÷÷ 16 ) = 65.5s ， Fosc=16KHz@3V |
| 0 | 1 | 1 | 1 / ( fcpu ÷ ÷ 16 ) = 1s ， Fosc=16KHz@3V |
| 1 | - | - | 1 / ( 16K ÷ 512 ÷ 16 ) ~ 0.5s @3V |