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6.6.3 PLL Control (PLLCTL)
PLL Controller Register Map
The PLL control register is shown in
and described in
for PLLC1 and PLLC2.
Figure 6-5. PLL Control Register (PLLCTL)
31
16
Reserved
R-0
R-0
15
9
8
Reserved
CLKMODE
R-0
R/W-0
R-0
R/W-0
7
6
5
4
3
2
1
0
Reserved
PLLENSRC
PLLDIS
PLLRST
Reserved
PLLPWRDN
PLLEN
R-1
R/W-1
R/W-1
R/W-1
R-0
R/W-1
R/W-0
R-1
R/W-1
R/W-1
R/W-1
R-0
R/W-1
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 6-6. PLL Control Register (PLLCTL) Field Descriptions
Bit
Field
Value
Description
31-9
Reserved
Reserved
8
CLKMODE
Reference Clock Selection. This bit has no effect for PLLC2. In DM355, a single oscillator or CLKIN
square wave is input to both PLLC1 and PLLC2.
0
Internal oscillator
1
CLKIN square wave
7-6
Reserved
Reserved
5
PLLENSRC
PLL enable source. This bit must be cleared to 0 before PLLCTL.PLLEN will have any effect.
0
PLL enable is controlled by the register bit PLLCTL.PLLEN
1
PLL enable is controlled by internal test hardware
4
PLLDIS
PLL disable
0
PLL disable de-assert
1
PLL disable assert
3
PLLRST
PLL reset
0
PLL reset de-assert
1
PLL reset assert
2
Reserved
Reserved
1
PLLPWRDN
PLL power-down
0
PLL operating, not powered down
1
PLL power-down
0
PLLEN
PLL Mode Enable. Bit PLLCTL.PLLENSRC must be cleared to 0 before PLLCTL.PLLEN will have
any effect.
0
Bypass mode
1
PLL mode, not bypassed
SPRUFB3 – September 2007
PLL Controllers (PLLCs)
47