Information

LLWU_F1 field descriptions (continued)
Field Description
4
WUF4
Wakeup Flag For LLWU_P4
Indicates that an enabled external wakeup pin was a source of exiting a low-leakage power mode. To
clear the flag write a one to WUF4.
0 LLWU_P4 input was not a wakeup source
1 LLWU_P4 input was a wakeup source
3
WUF3
Wakeup Flag For LLWU_P3
Indicates that an enabled external wakeup pin was a source of exiting a low-leakage power mode. To
clear the flag write a one to WUF3.
0 LLWU_P3 input was not a wakeup source
1 LLWU_P3 input was a wakeup source
2
WUF2
Wakeup Flag For LLWU_P2
Indicates that an enabled external wakeup pin was a source of exiting a low-leakage power mode. To
clear the flag write a one to WUF2.
0 LLWU_P2 input was not a wakeup source
1 LLWU_P2 input was a wakeup source
1
WUF1
Wakeup Flag For LLWU_P1
Indicates that an enabled external wakeup pin was a source of exiting a low-leakage power mode. To
clear the flag write a one to WUF1.
0 LLWU_P1 input was not a wakeup source
1 LLWU_P1 input was a wakeup source
0
WUF0
Wakeup Flag For LLWU_P0
Indicates that an enabled external wakeup pin was a source of exiting a low-leakage power mode. To
clear the flag write a one to WUF0.
0 LLWU_P0 input was not a wakeup source
1 LLWU_P0 input was a wakeup source
16.3.7 LLWU Flag 2 register (LLWU_F2)
LLWU_F2 contains the wakeup flags indicating which wakeup source caused the MCU
to exit LLS or VLLS mode. For LLS, this is the source causing the CPU interrupt flow.
For VLLS, this is the source causing the MCU reset flow.
The external wakeup flags are read-only and clearing a flag is accomplished by a write of
a 1 to the corresponding WUFx bit. The wakeup flag (WUFx), if set, will remain set if
the associated WUPEx bit is cleared.
Chapter 16 Low-Leakage Wakeup Unit (LLWU)
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
Freescale Semiconductor, Inc. 299