CPU documentation - General info

Clock settings - MCU Clock settings
- Source CPU clock - The clock source for all internal peripherals except the TBM timer . If the Internal and the External clock sources are enabled one of these clock sources can be specified in each speed mode.
- Internal clock - If this property is enabled the internal clock is allowed for MCU timing.
  Note: Processor Expert allows setting the requested frequency of the internal oscillator but the actual frequency depends on several conditions (temperature, etc.). In many real applications an accurate frequency is needed. In this case an adjustment of the internal clock frequency is necessary. This can be done by setting of the ICGTR register. Changing of this register increases or decreases the frequency of the internal oscillator and the desired frequency, which is set in Processor Expert, can be found. See the MCU documentation and application notes for details. The correct value of the trim register for the nominal frequency can be stored in the FLASH memory (by the manufacturer) and loaded in the trim register by the initialization code. This can be done by setting of the 'Initialize trim value' property.
  The following items are available only if the group is enabled (the value is "Enabled"):
  - Internal oscillator frequency [kHz] - Frequency of the internal oscillator.
  - Initialize trim value - This property enables to generate code for initialization of the trim register (ICGTR) by the value from a non-volatile memory location.
    The following items are available only if the group is enabled (the value is "yes"):
    - Trim value address - The location where the trim value is stored in the non-volatile memory.
- External clock - If this property is enabled, an external clock is allowed for MCU timing.
  The following items are available only if the group is enabled (the value is "Enabled"):
  - Clock Source - Possible external clock sources.
    There are 2 modes:
    - External crystal - The following items are displayed in this mode:
      - Clock frequency [MHz] - Frequency of the crystal or the external clock. The crystal frequency should be in range of 30kHz-100kHz or 1MHz-8MHz. The external clock frequency should be in range 0.0001-32MHz with ICG clock disabled or 60Hz-32MHz with ICG clock enabled. The valid frequency range of the external clock for current CPU component settings is shown in the third column of the 'Crystal speed / clock monitor freq.' property in the Component Inspector.
      - Crystal speed / clock monitor freq. - This property configures the ICG module for a fast (1 MHz to 8 MHz) or slow (30 kHz to 100 kHz) speed crystal. The option also configures the clock monitor operation in the ICG module to expect an external frequency higher (307.2 kHz to 32 MHz) or lower (60 Hz to 307.2 kHz) than the base frequency of the internal oscillator. The valid frequency range of the external clock for current CPU component settings is shown in the third column of the the Component Inspector.
      - Clock input - Clock input properties.
        
        Pin name - Clock input pin name (for information only).
      - Clock output - Clock output properties.
        
        Pin name - Clock output pin name (for information only).
    - External oscillator - The following items are displayed in this mode:
      - Clock frequency [MHz] - See previous modes for more details
      - Crystal speed / clock monitor freq. - See previous modes for more details
      - Clock input - Clock input properties.
        
        The content is the same as in previous modes.
- Clock Monitor - This property enables the Clock Monitor. The Clock Monitor can be turned on only if both Internal clock and External clock sources are enabled.
- MCLK output clock - MCLK output clock settings.
  The following items are available only if the group is enabled (the value is "Enabled"):
  - Clock output pin - MCLK output clock pin (for information only)
- Low-power modes settings - Low-power modes settings.
  - STOP instruction enabled - STOP instruction enabled
    The following items are available only if the group is enabled (the value is "Enabled"):
    - Oscillator Enable In Stop Mode - If this property is "yes" then the oscillator will be enabled in the STOP mode.
    - Recovery from Stop Mode after - This property enables the CPU to exit the stop mode with a delay of 32 CGMXCLK cycles instead of a 4096 CGMXCLK cycle delay.
- Internal bus clock - The internal bus clock [MHz]. Maximum bus frequency is 8.0MHz. This property can be modified only if the PLL is enabled. In the case of the internal oscillator, Processor Expert calculates the internal oscillator frequency from the desired bus clock frequency and possible range of the trim register (+-25%). User is responsible for the correct setting of the trim register if its value is other than 80h (0%). It is recommended to set the bus clock frequency as multiple of the nominal frequency of the internal oscillator 307.2kHz.
Maskable CPU interrupts - Enable/disable CPU maskable interrupts. This item modifies Interrupt Mask Bit I in Condition Code CPU register CCR.
Internal peripherals - Internal peripherals settings.
- LVI module - This property enables/disables low voltage monitoring on the Vdd pin.
  The following items are available only if the group is enabled (the value is "Enabled"):
  - LVI resets - This property enables/disables generating of LVI resets.
  - LVI Operating Mode - Operating mode of the LVI module.
  - LVI in stop mode - This property enables/disables LVI module in the stop mode.
- TBM module - TBM settings
  - TBM prescaler - Extra TBM prescaler.
    This item modifies the TMBCLKSEL bit in the CONFIG2 register.
CPU interrupts - Interrupts allocated by CPU bean
- Reset vector - Reset vector settings.
  - Interrupt - Interrupt associated with the reset vector (for information only)
  - ISR name - Name of the reset vector - routine, that initializes CPU after reset.
- Clock monitor - This property enables/disables generation of Clock monitor interrupt and its' interrupt service routine (Clock monitor must be turn on to enable Clock monitor interrupt - see property Clock monitor in the Clock settings group).
  The following items are available only if the group is enabled (the value is "Enabled"):
  - Interrupt - Clock monitor interrupt. (for information only)
  - ISR name - Name of the interrupt service routine (ISR) invoked by this interrupt vector.
    The user code of the routine should handle all respective interrupt flags correctly.
- SWI - This property enables/disables generation of SWI interrupt service routine.
  The following items are available only if the group is enabled (the value is "Enabled"):
  - Interrupt - Software Interrupt (for information only)
  - ISR name - Name of the interrupt service routine (ISR) invoked by this interrupt vector.
    The user code of the routine should handle all respective interrupt flags correctly.

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