Clock Generation
15-13
Clock Generation and System Reset Management
The MPU clock (see Figure 15–5) has the following domains (CLKM1):
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MPU processor clock: MPU_CK, which is CLK_GEN1 divided by 1, 2, 4,
or 8, as programmed via the ARMDIV bits of the MPU clock control
register (ARM_CKCTL). The idle mode of the MPU is controlled by the
SETARM_IDLE bit of the MPU idle mode entry 1 register (ARM_
IDLECT1).
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MPU peripheral clocks:
J
MPUXOR_CK, which is derived from CK_REF
J
MPUPER_CK, which is CLK_GEN1 divided by 1, 2, 4 or 8, as
programmed via the PERDIV bits of the MPU clock control register
(ARM_CKCTL)
The MPUPER_CLK clock is enabled by the EN_PERCK bit of the
MPU idle mode entry 2 register (ARM_IDLECT2) and the MPUX-
OR_CK clock by the EN_XORPCK bit.
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MPU watchdog timer clock (low frequency, derived from CK_REF/14):
Called either CK_CLKIN14 or MPUWD_CK. This clock is enabled by the
EN_WDTCK bit of the MPU idle mode entry 2 register (ARM_IDLECT2).
The IDLE mode is controlled by the IDLWDT_ARM bit of the MPU idle
mode entry 1 register (ARM_IDLECT1). The clock cannot be disabled or
idled while in the watchdog mode.
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MPU internal timers clock: MPUTIM_CK, which is derived from either
CK_GEN1 or CK_REF, as selected by the ARM_TIMXO bit of the MPU
clock control register (ARM_CKCTL). The IDLE mode of the MPU timers
is controlled by the IDLTIM_ARM bit of the MPU idle mode entry 1 register
(ARM_IDLECT1) and is enabled by the EN_TIMCK bit of the MPU idle
mode entry 2 register (ARM_IDLECT2).
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MPU GPIO, MPU_GPIO_CLK, which is equal to CK_GEN1. This clock is
enabled by the EN_GPIOCK bit of the the MPU idle mode entry 2 register
(ARM_IDLECT2).