
Clock Module
7-8
Freescale Semiconductor
7.2.4
PLL Feedback Divider Register (PFDR)
7.3
Functional Description
This subsection provides a functional description of the clock module.
7.3.1
PLL Dithered and Non-Dithered Operation
The PLL is capable of generating output clocks with a frequency that modulates in a triangular waveform
with a specified percentage frequency deviation and a specified dither modulation frequency. This
modulation of the output clock is called dithered operation. When the PLL operates at a fixed frequency,
Table 7-5. PMDR Field Descriptions
Field
Description
7–0
MODDIV
Dither modulation divider.
Dither Modulation Frequency = Input Frequency / (MODDIV
×
32)
A dither modulation frequency greater than 105 kHz or less than 9.95 kHz is invalid. For example, for a 16 MHz input
frequency, MODDIV may be programmed between 5 (100 kHz) and 50 (10 kHz). Programming MODDIV outside
the specified range results in unpredictable PLL operation.
Note: This field should only be written when dithering mode is disabled (PCR[DITHEN] = 0). Else, unpredictable PLL
operation results.
Address: 0xFC0C_000C (PFDR)
Access: User read/write
7
6
5
4
3
2
1
0
R
MFD
W
Reset:
See Note
See Note
See Note
See Note
See Note
See Note
See Note
See Note
Note: Reset value determined by reset configuration. See
Chapter 9, “Chip Configuration Module (CCM),”
for
more information. For the default reset configuration (RCON negated), the reset value is 0x5A. If RCON
and D1 is asserted at reset, the reset value of PFDR is 0x78.
Figure 7-6. PLL Feedback Divider Register (PFDR)
Table 7-6. PFDR Field Descriptions
Field
Description
7–0
MFD
The MFD bits control the value of the divider in the PLL feedback loop. The value specified by the MFD bits establish
the multiplication factor applied to the reference frequency. See
Section 7.3.3, “PLL Frequency Multiplication Factor
for more details.
0x58 88
0x59 89
0x5A 90
...
0x86 134
0x87 135
Else Reserved
Note: The MFD bits may only be written when the device is in limp mode (MISCCR[LIMP] = 1).
MCF5329 Reference Manual, Rev 3
Summary of Contents for MCF5329
Page 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...