FUJITSU MB91F109 FR30 - Manual (Page 92)

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CHAPTER 2 CPU
2.9 Reset Sequence
This section explains CPU resetting.
■ Causes of Resetting
The causes of resetting are as follows:
• Input from an external reset pin
• Software reset by manipulation of the SRST bit of standby control register (STCR)
• Expiration of watchdog timer
• Power-on reset
■ Initialization by Resetting
When a cause for resetting occurs, the CPU is initialized.
❍ Releasing from the external reset pin or software reset
• The pin is set to the predetermined state.
• Each resource in the device is put in the reset state. The control register is initialized to the
predetermined value.
• The lowest gear is selected for the clock frequency.
■ Reset Sequence
After the cause of resetting is cleared, the CPU executes the following reset sequence:
• (000FFFFC
H
) --> PC
After the CPU is reset, the operation mode is defined in details using the mode register.
For details, see the description of the mode register in Section 2.10, "Operation Mode."