MPC555
/
MPC556
CLOCKS AND POWER CONTROL
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
8-34
8.12.3 Change of Lock Interrupt Register (COLIR)
The COLIR is 16-bit read/write register. It controls the change of lock interrupt gener-
ation, and is used for reporting a loss of lock interrupt source. It contains the interrupt
request level and the interrupt status bit. This register is readable and writable at any
time. A status bit is cleared by writing a one (writing a zero does not affect a status bit’s
value). The COLIR is memory mapped into the MPC555 / MPC556 USIU register map.
U = Unaffected by reset
8.12.4 VDDSRAM Control Register (VSRMCR)
This register contains control bits for enabling or disabling the VDDSRAM supply de-
tection circuit. There are also four bits that indicate the failure detection. All four bits
have the same function and are required to improve the detection capability in extreme
cases.
26
—
Reserved
27:31
DIVF
The DIVF bits control the value of the pre-divider in the SPLL circuit. The DIVF bits can be
read and written at any time. However, the DIVF field can be write-protected by setting the
MF and pre-divider lock (MFPDL) bit in the SCCR. Changing the DIVF bits causes the SPLL
to lose lock.
COLIR
— Change of Lock Interrupt Register
0x2F C28C
MSB
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
LSB
15
COLIRQ
COLIS
Re-
served
COLIE
Reserved
RESET:
0
0
0
0
0
0
0
0
0
0
U
U
U
U
U
U
Table 8-11 COLIR Bit Descriptions
Bit(s)
Name
Description
0:7
COLIRQ
Change of lock interrupt request level. These bits determine the interrupt priority level of the
change of lock. To specify certain level, the appropriate one of these bits should be set.
8
COLIS
If set (“one”), the bit indicates that a change in the PLL lock status was detected. The PLL
was locked and lost lock, or the PLL was unlocked and got locked. The bit should be cleared
by writing a one.
9
—
Reserved
10
COLIE
Change of Lock Interrupt enable. If COLIE bit is asserted, an interrupt will generate when the
COLIS bit is asserted.
0 = Change of lock Interrupt disable
1 = Change of lock Interrupt enable
10:15
—
Reserved
Table 8-10 PLPRCR Bit Descriptions (Continued)
Bit(s)
Name
Description
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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