The maximum clock frequency for the P89LPC9381FDH,512 is 3.5 MHz, but it can be overclocked up to 5 MHz with some limitations.
The oscillator can be configured using the OSCCFG register. The oscillator frequency can be selected by setting the appropriate values for the OSCCFG bits. Additionally, the oscillator can be enabled or disabled using the OSCEN bit.
The watchdog timer is used to reset the microcontroller if it becomes stuck in an infinite loop or if it fails to respond within a certain time period. This is useful for ensuring system reliability and preventing system crashes.
The UART can be used by configuring the UART registers, such as the UART control register, the UART status register, and the UART data register. The UART can be used for asynchronous communication with other devices.
The power consumption of the P89LPC9381FDH,512 depends on the operating frequency, voltage, and other factors. According to the datasheet, the typical power consumption is around 10 mA at 3.5 MHz and 3.3 V.