Table 24-15. MCGOUTCLK Frequency Calculation Options
Clock Mode
f
MCGOUTCLK
Note
FEI (FLL engaged internal)
(f
int
* F)
Typical f
MCGOUTCLK
= 20 MHz
immediately after reset.
FEE (FLL engaged external)
(f
ext
/ FLL_R) *F
f
ext
/ FLL_R must be in the range of
31.25 kHz to 39.0625 kHz
FBE (FLL bypassed external)
f
ext
f
ext
/ FLL_R must be in the range of
31.25 kHz to 39.0625 kHz
FBI (FLL bypassed internal)
f
int
Typical f
int
= 32 kHz
PEE (PLL engaged external)
(f
ext
/ PLL_R) * M
f
ext
/ PLL_R must be in the range of
2 – 4 MHz
PBE (PLL bypassed external)
f
ext
f
ext
/ PLL_R must be in the range of
2 – 4 MHz
BLPI (Bypassed low power internal)
f
int
BLPE (Bypassed low power external)
f
ext
1. FLL_R is the reference divider selected by the C1[FRDIV] bits, PLL_R is the reference divider selected by C5[PRDIV] bits,
F is the FLL factor selected by C4[DRST_DRS] and C4[DMX32] bits, and M is the multiplier selected by C6[VDIV] bits.
This section will include 3 mode switching examples using an 4 MHz external crystal. If
using an external clock source less than 2 MHz, the MCG should not be configured for
any of the PLL modes (PEE and PBE).
24.5.3.1 Example 1: Moving from FEI to PEE Mode : External Crystal
= 4 MHz, MCGOUTCLK Frequency = 48 MHz
In this example, the MCG will move through the proper operational modes from FEI to
PEE to achieve 48 MHz MCGOUTCLK frequency from 4 MHz external crystal
reference. First, the code sequence will be described. Then a flowchart will be included
which illustrates the sequence.
1. First, FEI must transition to FBE mode:
a. C2 = 0x1C
• C2[RANGE] set to 2'b01 because the frequency of 4 MHz is within the high
frequency range
• C2[HGO] set to 1 to configure the crystal oscillator for high gain operation
• C2[EREFS] set to 1, because a crystal is being used
b. C1 = 0x90
Initialization / Application Information
K53 Sub-Family Reference Manual, Rev. 6, Nov 2011
574
Freescale Semiconductor, Inc.
Содержание K53 Series
Страница 2: ...K53 Sub Family Reference Manual Rev 6 Nov 2011 2 Freescale Semiconductor Inc...
Страница 58: ...K53 Sub Family Reference Manual Rev 6 Nov 2011 58 Freescale Semiconductor Inc...
Страница 70: ...Orderable part numbers K53 Sub Family Reference Manual Rev 6 Nov 2011 70 Freescale Semiconductor Inc...
Страница 168: ...Human machine interfaces HMI K53 Sub Family Reference Manual Rev 6 Nov 2011 168 Freescale Semiconductor Inc...
Страница 206: ...Boot K53 Sub Family Reference Manual Rev 6 Nov 2011 206 Freescale Semiconductor Inc...
Страница 218: ...Security Interactions with other Modules K53 Sub Family Reference Manual Rev 6 Nov 2011 218 Freescale Semiconductor Inc...
Страница 342: ...PMC Memory Map Register Definition K53 Sub Family Reference Manual Rev 6 Nov 2011 342 Freescale Semiconductor Inc...
Страница 362: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 362 Freescale Semiconductor Inc...
Страница 384: ...Initialization application information K53 Sub Family Reference Manual Rev 6 Nov 2011 384 Freescale Semiconductor Inc...
Страница 406: ...Application Information K53 Sub Family Reference Manual Rev 6 Nov 2011 406 Freescale Semiconductor Inc...
Страница 424: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 424 Freescale Semiconductor Inc...
Страница 514: ...Initialization application information K53 Sub Family Reference Manual Rev 6 Nov 2011 514 Freescale Semiconductor Inc...
Страница 524: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 524 Freescale Semiconductor Inc...
Страница 546: ...Restrictions on Watchdog Operation K53 Sub Family Reference Manual Rev 6 Nov 2011 546 Freescale Semiconductor Inc...
Страница 594: ...Interrupts K53 Sub Family Reference Manual Rev 6 Nov 2011 594 Freescale Semiconductor Inc...
Страница 628: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 628 Freescale Semiconductor Inc...
Страница 702: ...Flash Operation in Low Power Modes K53 Sub Family Reference Manual Rev 6 Nov 2011 702 Freescale Semiconductor Inc...
Страница 772: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 772 Freescale Semiconductor Inc...
Страница 808: ...Initialization Application Information K53 Sub Family Reference Manual Rev 6 Nov 2011 808 Freescale Semiconductor Inc...
Страница 864: ...Application information K53 Sub Family Reference Manual Rev 6 Nov 2011 864 Freescale Semiconductor Inc...
Страница 894: ...DAC Interrupts K53 Sub Family Reference Manual Rev 6 Nov 2011 894 Freescale Semiconductor Inc...
Страница 908: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 908 Freescale Semiconductor Inc...
Страница 920: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 920 Freescale Semiconductor Inc...
Страница 926: ...Functional Description K53 Sub Family Reference Manual Rev 6 Nov 2011 926 Freescale Semiconductor Inc...
Страница 1092: ...FTM Interrupts K53 Sub Family Reference Manual Rev 6 Nov 2011 1092 Freescale Semiconductor Inc...
Страница 1114: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 1114 Freescale Semiconductor Inc...
Страница 1156: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 1156 Freescale Semiconductor Inc...
Страница 1304: ...On The Go Operation K53 Sub Family Reference Manual Rev 6 Nov 2011 1304 Freescale Semiconductor Inc...
Страница 1334: ...USB Voltage Regulator Module Signal Descriptions K53 Sub Family Reference Manual Rev 6 Nov 2011 1334 Freescale Semiconductor Inc...
Страница 1388: ...Initialization Application Information K53 Sub Family Reference Manual Rev 6 Nov 2011 1388 Freescale Semiconductor Inc...
Страница 1514: ...Application information K53 Sub Family Reference Manual Rev 6 Nov 2011 1514 Freescale Semiconductor Inc...
Страница 1622: ...Software restrictions K53 Sub Family Reference Manual Rev 6 Nov 2011 1622 Freescale Semiconductor Inc...
Страница 1694: ...Initialization application information K53 Sub Family Reference Manual Rev 6 Nov 2011 1694 Freescale Semiconductor Inc...
Страница 1704: ...Functional description K53 Sub Family Reference Manual Rev 6 Nov 2011 1704 Freescale Semiconductor Inc...
Страница 1734: ...Application information K53 Sub Family Reference Manual Rev 6 Nov 2011 1734 Freescale Semiconductor Inc...
Страница 1800: ...Application information K53 Sub Family Reference Manual Rev 6 Nov 2011 1800 Freescale Semiconductor Inc...
Страница 1822: ...K53 Sub Family Reference Manual Rev 6 Nov 2011 1822 Freescale Semiconductor Inc...