10.3 Fusion Peripherals
Supported Families
This core is supported by only the Fusion family.
Crystal Oscillator Summary
You must set the mode of the crystal oscillator:
RTC - Real-time counter . If you are using a RTC in your design, then you must use the RTC mode for your crystal oscillator.
The SELMODE and RTCMODE pins exported in this configuration must be connected to the same signals exported from the Analog System Builder. The CLKOUT output must drive the RTC clock.
There is an optional output port that drives the internal logic.
The frequency of the XTL signal must match the frequency specified during the RTC peripheral configuration (see the Analog System Builder User Guide).
- External Crystal or Ceramic Resonator
- Oscillator is configured to work with an external crystal or ceramic resonator.
Based on the frequency specified and the crystal oscillator mode selection, the core configurator software automatically configures the mode, as shown in the following table:
| Mode | Recommended Capacitor | Frequency Range |
|---|---|---|
| LOW_GAIN | 100 pf | 0.032 to 0.20 |
| MEDIUM_GAIN | 100 pf | 0.21 to 2.0 |
| HIGH_GAIN | 15 pf | 2.1 to 20.0 |
- RC Network
- Oscillator is configured to work with an external resistor-capacitor network.