High-Performance

Fast Internal RC Oscillator Control Status Register offset 0x300.

Fast Internal RC Oscillator Control Status Register offset 0x300Controls and monitors the Fast Internal RC Oscillator (FIRC), which provides high-frequency internal clock generation for general system operation with good performance and moderate power consumption.

快速內部RC振盪器控制狀態暫存器，高頻內部時脈源

FIRC Functions:

• High-frequency internal oscillator (~48 MHz typical)
• Good balance of performance and power consumption
• Automatic trimming for improved accuracy
• Multiple frequency range selections
• Fast startup suitable for dynamic clock switching

註

FIRC Characteristics:

• Medium power consumption (higher than SIRC, lower than SOSC)
• Good frequency accuracy with trimming (±1-3% typical)
• Fast startup time (10s of microseconds)
• No external components required

• Suitable for general-purpose system clock

  Internal Clock:

  // Configure FIRC for maximum performance
  scg->firccsr = FIRC_ENABLE | FIRC_HIGH_RANGE | FIRC_AUTO_TRIM_ENABLE;
  while (!(scg->firccsr & FIRC_VALID_FLAG));
   
  // Switch system clock to FIRC
  scg->rccr = (scg->rccr & ~CLOCK_SOURCE_MASK) | CLOCK_SOURCE_FIRC;