MC9S12P64CFT datasheet by Freescale Semiconductor

MC9S12P64CFT Frequently Asked Questions (FAQs)

• What is the maximum clock frequency that can be used with the internal oscillator?
  The maximum clock frequency that can be used with the internal oscillator is 20 MHz, but it's recommended to use a crystal oscillator for frequencies above 10 MHz for better stability and accuracy.
• How do I configure the chip select signals for the external memory interface?
  The chip select signals can be configured using the MEMCTL register. You need to set the CSxEN bits to enable the corresponding chip select signals and configure the CSxADDR registers to define the address range for each chip select signal.
• What is the maximum current that can be sourced or sunk by the GPIO pins?
  The maximum current that can be sourced or sunk by the GPIO pins is 25 mA. However, it's recommended to limit the current to 10 mA or less to ensure reliable operation and prevent overheating.
• How do I implement a watchdog timer reset?
  To implement a watchdog timer reset, you need to enable the watchdog timer by setting the WDE bit in the WMR register. Then, you need to periodically reset the watchdog timer by writing a specific value to the WVR register. If the watchdog timer is not reset within the specified time period, it will generate a reset signal.
• What is the purpose of the COP (Computer Operating Properly) module?
  The COP module is a watchdog timer that monitors the operation of the microcontroller and generates a reset signal if the microcontroller fails to respond within a specified time period. This is useful for detecting and recovering from software faults or hangs.