User manual
...the world's most energy friendly microcontrollers
2012-04-24 - Giant Gecko Family - d0053_Rev0.96 142
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Bit Name Reset Access Description
10:8 BAND 0x0 RW AUXHFRCO Band Select
Write this field to set the frequency band in which the AUXHFRCO is to operate. When changing this setting there will be no glitches
on the HFRCO output, hence it is safe to change this setting even while the system is using the AUXHFRCO. To ensure an accurate
frequency, the AUXTUNING value should also be written when changing the frequency band. The calibrated tuning value for the
different bands can be read from the Device Information page. Flash erase and write use this clock. If it is changed to another value
than the default, MSC_TIMEBASE must also be configured to ensure correct flash erase and write operation.
Value Mode Description
0 14MHZ 14 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
1 11MHZ 11 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
2 7MHZ 7 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
3 1MHZ 1 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
6 28MHZ 28 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
7 21MHZ 21 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
7:0 TUNING 0x80 RW AUXHFRCO Tuning Value
This value has been set during calibration and should not be changed.
11.5.7 CMU_CALCTRL - Calibration Control Register
Offset Bit Position
0x018
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Reset
0
0x0
0x0
Access
RW
RW
RW
Name
CONT
DOWNSEL
UPSEL
Bit Name Reset Access Description
31:7 Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
6 CONT 0 RW Continuous Calibration
Set this bit to enable continuous calibration
5:3 DOWNSEL 0x0 RW Calibration Down-counter Select
Selects clock source for the calibration down-counter
Value Mode Description
0 HFCLK Select HFCLK for down-counter
1 HFXO Select HFXO for down-counter
2 LFXO Select LFXO for down-counter
3 HFRCO Select HFRCO for down-counter
4 LFRCO Select LFRCO for down-counter
5 AUXHFRCO Select AUXHFRCO for down-counter
2:0 UPSEL 0x0 RW Calibration Up-counter Select
Selects clock source for the calibration up-counter
Value Mode Description
0 HFXO Select HFXO as up-counter
1 LFXO Select LFXO as up-counter
2 HFRCO Select HFRCO as up-counter
3 LFRCO Select LFRCO as up-counter
4 AUXHFRCO Select AUXHFRCO as up-counter