SAM4L Datasheet, PDF (230/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

ATSAM4L4/L2
13.7.14 DFLLx Spread Spectrum Generator Control Register
Name:
Access Type:
Reset Value:
DFLLxSSG
Read/Write
0x00000000
31
30
29
28
27
26
25
24
-
-
-
-
-
-
-
-
23
22
21
20
19
18
17
16
-
-
-
STEPSIZE
15
14
13
12
11
10
9
8
-
-
-
AMPLITUDE
7
6
5
4
3
2
1
0
-
-
-
-
-
-
PRBS
EN
• STEPSIZE: SSG Step Size
Selects the step size of the spread spectrum. If zero or one, the value added to the FINE bits will be incremented/decremented
with one on every positive edge of the input clock. If n > 1, the value added to the FINE bits will be incremented/decremented
with n on every positive edge of the input clock.
• AMPLITUDE: SSG Amplitude
Selects the amplitude of the spread spectrum. If zero, only the LSB of the FINE bits will be affected. If one, the sequence {1, 0,
-1, 0} will be added to FINE bits, etc.
• PRBS: Pseudo Random Bit Sequence
0: Each spread spectrum frequency is applied at constant intervals
1: Each spread spectrum frequency is applied at pseudo-random intervals
• EN: Enable
0: SSG is disabled.
1: SSG is enabled.
Note that this register is protected by a lock. To write to this register the UNLOCK register has to be written first. Refer to
Section 13.7.7 ”Unlock Register” on page 222 for details.
42023C–SAM–02/2013
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