Datasheet

DescriptionResetTypeNameBit/Field
Crystal Value
This field specifies the crystal value attached to the main oscillator. The
encoding for this field is provided below. Depending on the crystal used,
the PLL frequency may not be exactly 400 MHz (see Table
23-10 on page 752 for more information).
Crystal Frequency (MHz) Using
the PLL
Crystal Frequency (MHz) Not
Using the PLL
Value
reserved1.0000x0
reserved1.84320x1
reserved2.0000x2
reserved2.45760x3
3.579545 MHz0x4
3.6864 MHz0x5
4 MHz0x6
4.096 MHz0x7
4.9152 MHz0x8
5 MHz0x9
5.12 MHz0xA
6 MHz (reset value)0xB
6.144 MHz0xC
7.3728 MHz0xD
8 MHz0xE
8.192 MHz0xF
0xBR/WXTAL9:6
Oscillator Source
Selects the input source for the OSC. The values are:
Input SourceValue
MOSC
Main oscillator
0x0
IOSC
Internal oscillator (default)
0x1
IOSC/4
Internal oscillator / 4
0x2
30 kHz
30-KHz internal oscillator
0x3
For additional oscillator sources, see the RCC2 register.
0x1R/WOSCSRC5:4
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
0x0ROreserved3:2
Internal Oscillator Disable
0: Internal oscillator (IOSC) is enabled.
1: Internal oscillator is disabled.
0R/WIOSCDIS1
June 18, 2012200
Texas Instruments-Production Data
System Control
NRND: Not recommended for new designs.