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are not implemented).

3. OSC1 and OSC2 pins connect a crystal/ceramic resonator, an RC oscillator, or an external source to

the on-chip oscillator;

4. On the chip, each I/O port has 8 pads. Pads that are not bonded to external pins are in input pull-up con-

figuration after reset. The configuration of these pads must be kept at reset state to avoid added current

consumption.