Datasheet

Table Of Contents
194
SAM9N12/SAM9CN11/SAM9CN12 [DATASHEET]
11063K–ATARM–05-Nov-13
22.12.8 PMC Clock Generator Main Clock Frequency Register
Name: CKGR_MCFR
Address: 0xFFFFFC24
Access: Read-write
MAINF: Main Clock Frequency
Gives the number of Main Clock cycles within 16 Slow Clock periods.
MAINFRDY: Main Clock Ready
0: MAINF value is not valid or the Main Oscillator is disabled.
1: The Main Oscillator has been enabled previously and MAINF value is available.
Note: To ensure reading a correct value on MAINF field, the MAINFRDY flag must be read at 1, then another read access
must be performed on the register to get a stable value on MAINF field.
RCMEAS: RC Measure
This bit is write-only.
0: No effect.
1: Restart a measure of the main RC frequency. MAINF will carry the new frequency as soon as a low to high transition occurs on
MAINFRDY flag.
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
–––RCMEAS–––MAINFRDY
15 14 13 12 11 10 9 8
MAINF
76543210
MAINF