Information

• C1[IREFS] set to 1 to select the internal reference clock as the reference
clock source.
• C1[FRDIV] remain unchanged because the reference divider does not affect
the internal reference.
b. Loop until S[IREFST] is 1, indicating the internal reference clock has been
selected as the reference clock source.
c. Loop until S[CLKST] are 2'b01, indicating that the internal reference clock is
selected to feed MCGOUTCLK.
4. Lastly, FBI transitions into BLPI mode.
a. C2 = 0x02
• C2[LP] is 1
• C2[RANGE0], C2[HGO0], C2[EREFS0], C1[IRCLKEN], and
C1[IREFSTEN] bits are ignored when the C1[IREFS] bit is set. They can
remain set, or be cleared at this point.
Chapter 24 Multipurpose Clock Generator (MCG)
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
Freescale Semiconductor, Inc. 461