MMC2114 MOTOROLA [Motorola, Inc], MMC2114 Datasheet - Page 255

• Manufacturer Part Number: MMC2114
• Description: M CORE Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

MMC2114 • MMC2113 • MMC2112 — Rev. 1.0
MOTOROLA
LOCK — PLL Lock Flag
LOCS — Sticky Loss Of Clock Flag
When the PLL loses lock, LOCKS is cleared. When the PLL relocks,
LOCKS remains cleared until one of the two listed events occurs.
In stop mode, if the PLL is intentionally disabled, then the LOCKS bit
reflects the value prior to entering stop mode. However, if FWKUP is
set, then LOCKS is cleared until the PLL regains lock. Once lock is
regained, the LOCKS bit reflects the value prior to entering stop
mode. Furthermore, reading the LOCKS bit at the same time that the
PLL loses lock does not return the current loss of lock condition.
In external clock mode, LOCKS remains cleared after reset. In normal
PLL mode and 1:1 PLL mode, LOCKS is set after reset.
The LOCK flag is set when the PLL is locked. PLL lock occurs when
the synthesized frequency is within approximately 0.75 percent of the
programmed frequency. The PLL loses lock when a frequency
deviation of greater than approximately 1.5 percent occurs. Reading
the LOCK flag at the same time that the PLL loses lock or acquires
lock does not return the current condition of the PLL. The power-on
reset circuit uses the LOCK bit as a condition for releasing reset.
If operating in external clock mode, LOCK remains cleared after reset.
The LOCS flag is a sticky indication of whether a loss of clock
condition has occurred at any time since exiting reset in normal PLL
and 1:1 PLL modes. LOCS = 0 when the system clocks are operating
normally. LOCS = 1 when system clocks have failed due to a
reference failure or PLL failure.
After entering stop mode with FWKUP set and the PLL and oscillator
intentionally disabled (STPMD[1:0] = 11), the PLL exits stop mode in
SCM while the oscillator starts up. During this time, LOCS is
temporarily set regardless of LOCEN. It is cleared once the oscillator
comes up and the PLL is attempting to lock.
Freescale Semiconductor, Inc.
For More Information On This Product,
1 = PLL locked
0 = PLL not locked
1 = Loss of clock detected since exiting reset or oscillator not yet
0 = Loss of clock not detected since exiting reset
recovered from exit from stop mode with FWKUP = 1
Go to: www.freescale.com
Clock Module
Memory Map and Registers
Advance Information
Clock Module
255