Silicon Laboratories Si446 Series, Руководство пользователя

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AN625
Rev. 0.1 53
3.5.18. GLOBAL_XO_TUNE
 Summary: Configure crystal oscillator frequency tuning bank
 Purpose:

Crystal oscillator frequency tuning value. 0x00 is maximum frequency value and 0x7F is lowest frequency value. Each
LSB code corresponds to a 70fF capacitance change. The total adjustment range assuming a 30MHz XTAL is +/-100ppm.
 Property: 0x0000
 Default: 0x40
 Fields:

TUNE_VALUE[6:0] - default:0x40
0 = Maximum frequency
127 = Lowest frequency
 Register View
3.5.19. GLOBAL_CLK_CFG
 Summary: Clock configuration options
 Purpose:

 Property: 0x0001
 Default: 0
 Fields:

DIVIDED_CLK_EN - default:0
0 = Divided clock output is disabled.
1 = Divided clock output is enabled.

DIVIDED_CLK_SEL[2:0] - default:0x0
0 = Clock output is system clock divided by 1.
1 = Clock output is system clock divided by 2.
2 = Clock output is system clock divided by 3.
3 = Clock output is system clock divided by 7.5.
4 = Clock output is system clock divided by 10.
5 = Clock output is system clock divided by 15.
6 = Clock output is system clock divided by 30.

CLK_32K_SEL[2:0] - default:0x0
0 = 32 kHz clock is disabled
1 = 32 kHz clock is driven by internal RC oscillator
2 = 32 kHz clock is driven by External crystal
 Register View
GLOBAL_XO_TUNE
7 6 5 4 3 2 1 0
0 TUNE_VALUE[6:0]
0 0x40
GLOBAL_CLK_CFG
7 6 5 4 3 2 1 0
0 DIVIDED_CLK_EN DIVIDED_CLK_SEL[2:0] CLK_32K_SEL[2:0]
0 0 0x0 0x0