12.5.9 Internal High-Frequency Oscillator Frequency Tune
| Name: | OSCHFTUNE |
| Offset: | 0x09 |
| Reset: | 0x00 |
| Property: | - |
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| TUNE[6:0] | |||||||||
| Access | R/W | R/W | R/W | R/W | R/W | R/W | R/W | ||
| Reset | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ||
Bits 6:0 – TUNE[6:0] Oscillator Frequency Tune
This bit field controls the manual tuning of the output frequency of the internal high-frequency oscillator (OSCHF). The frequency can be tuned 32 steps down or 31 up from the oscillator’s target frequency. Thus, the register’s acceptable input value range is -32 to +31.
Writing to bit 6 has no effect, as bit 5 will be mirrored to bit 6 due to the 6-bit value in this bit field being represented in a signed (two’s complement) form.
Note: If the Auto-Tune
Enable (AUTOTUNE) bit field in the Internal High-Frequency Oscillator Control A
(CLKCTRL.OSCHFCTRLA) register is written with a value other than ‘0’, the TUNE value is
locked. When AUTOTUNE is disabled, it takes up to three µs and three Main Clock cycles
before this bit field is updated with the latest tune value from the auto-tune operation.