User manual
...the world's most energy friendly microcontrollers
2012-04-24 - Giant Gecko Family - d0053_Rev0.96 141
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Bit Name Reset Access Description
10:8 BAND 0x3 RW HFRCO Band Select
Write this field to set the frequency band in which the HFRCO 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 running on the HFRCO. To ensure an accurate
frequency, the HFTUNING 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.
Value Mode Description
0 1MHZ 1 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
1 7MHZ 7 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
2 11MHZ 11 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
3 14MHZ 14 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
4 21MHZ 21 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
5 28MHZ 28 MHz. NOTE: Also set the TUNING value (bits 7:0) when changing band.
7:0 TUNING 0x80 RW HFRCO Tuning Value
Writing this field adjusts the HFRCO frequency (the higher value, the higher frequency). This field is updated with the production
calibrated value for the 14 MHz band during reset, and the reset value might therefore vary between devices.
11.5.5 CMU_LFRCOCTRL - LFRCO Control Register
Offset Bit Position
0x010
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
0x40
Access
RW
Name
TUNING
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)
6:0 TUNING 0x40 RW LFRCO Tuning Value
Writing this field adjusts the LFRCO frequency (the higher value, the higher frequency). This field is updated with the production
calibrated value during reset, and the reset value might therefore vary between devices.
11.5.6 CMU_AUXHFRCOCTRL - AUXHFRCO Control Register
Offset Bit Position
0x014
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
0x0
0x80
Access
RW
RW
Name
BAND
TUNING
Bit Name Reset Access Description
31:11 Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)