rp2040_pac

Module rosc

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Expand description

ROSC

Modules§

  • Ring Oscillator control
  • Controls the output divider
  • Ring Oscillator pause control
    This is used to save power by pausing the ROSC
    On power-up this field is initialised to WAKE
    An invalid write will also select WAKE
    Warning: setup the irq before selecting dormant mode
  • The FREQA & FREQB registers control the frequency by controlling the drive strength of each stage
    The drive strength has 4 levels determined by the number of bits set
    Increasing the number of bits set increases the drive strength and increases the oscillation frequency
    0 bits set is the default drive strength
    1 bit set doubles the drive strength
    2 bits set triples drive strength
    3 bits set quadruples drive strength
  • For a detailed description see freqa register
  • Controls the phase shifted output
  • This just reads the state of the oscillator output so randomness is compromised if the ring oscillator is stopped or run at a harmonic of the bus frequency
  • Ring Oscillator Status

Structs§

Type Aliases§

  • CTRL (rw) register accessor: Ring Oscillator control
  • DIV (rw) register accessor: Controls the output divider
  • DORMANT (rw) register accessor: Ring Oscillator pause control
    This is used to save power by pausing the ROSC
    On power-up this field is initialised to WAKE
    An invalid write will also select WAKE
    Warning: setup the irq before selecting dormant mode
  • FREQA (rw) register accessor: The FREQA & FREQB registers control the frequency by controlling the drive strength of each stage
    The drive strength has 4 levels determined by the number of bits set
    Increasing the number of bits set increases the drive strength and increases the oscillation frequency
    0 bits set is the default drive strength
    1 bit set doubles the drive strength
    2 bits set triples drive strength
    3 bits set quadruples drive strength
  • FREQB (rw) register accessor: For a detailed description see freqa register
  • PHASE (rw) register accessor: Controls the phase shifted output
  • RANDOMBIT (r) register accessor: This just reads the state of the oscillator output so randomness is compromised if the ring oscillator is stopped or run at a harmonic of the bus frequency
  • STATUS (r) register accessor: Ring Oscillator Status