LM3S6G11 Datasheet, PDF (267/827 Pages) Texas Instruments – Stellaris® LM3S6G11 Microcontroller

OBSOLETE: TI has discontinued production of this device.
Stellaris^® LM3S6G11 Microcontroller
6.4.2
6.4.3
1. Write 0x44 to the HIBCTL register at offset 0x10 to enable the oscillator input and bypass the
on-chip oscillator.
2. No delay is necessary.
The above steps are only necessary when the entire system is initialized for the first time. If the
microcontroller has been in hibernation, then the Hibernation module has already been powered
up and the above steps are not necessary. The software can detect that the Hibernation module
and clock are already powered by examining the CLK32EN bit of the HIBCTL register.
Table 6-3 on page 267 illustrates how the clocks function with various bit setting both in normal
operation and in hibernation.
Table 6-3. Hibernation Module Clock Operation
CLK32EN PINWEN RTCWEN CLKSEL RTCEN Result Normal Operation
Result Hibernation
0
X
X
X
X Hibernation module disabled
Hibernation module disabled
1
0
0
0
1 RTC match capability enabled. No hibernation
Module clocked from
4.184304-MHz crystal.
1
0
0
1
1 RTC match capability enabled. No hibernation
Module clocked from 32.768-kHz
oscillator.
1
0
1
X
1 Module clocked from selected RTC match for wake-up event
source
1
1
0
X
0 Module clocked from selected Clock is powered down during
source
hibernation and powered up again
on external wake-up event.
1
1
0
X
1 Module clocked from selected Clock is powered up during
source
hibernation for RTC. Wake up on
external event.
1
1
1
X
1 Module clocked from selected RTC match or external wake-up
source
event, whichever occurs first.
RTC Match Functionality (No Hibernation)
Use the following steps to implement the RTC match functionality of the Hibernation module:
1. Write the required RTC match value to one of the HIBRTCMn registers at offset 0x004 or 0x008.
2. Write the required RTC load value to the HIBRTCLD register at offset 0x00C.
3. Set the required RTC match interrupt mask in the RTCALT0 and RTCALT1 bits (bits 1:0) in the
HIBIM register at offset 0x014.
4. Write 0x0000.0041 to the HIBCTL register at offset 0x010 to enable the RTC to begin counting.
RTC Match/Wake-Up from Hibernation
Use the following steps to implement the RTC match and wake-up functionality of the Hibernation
module:
1. Write the required RTC match value to the HIBRTCMn registers at offset 0x004 or 0x008.
2. Write the required RTC load value to the HIBRTCLD register at offset 0x00C.
July 24, 2012
267
Texas Instruments-Production Data