GD32VF103 User Manual
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5.
Reset and clock unit (RCU)
5.1.
Reset control unit (RCTL)
5.1.1.
Overview
GD32VF103 Reset Control includes the control of three kinds of reset: power reset, system
reset and backup domain reset. The power reset, known as a cold reset, resets the full system
except the Backup domain. The system reset resets the processor core and peripheral IP
components except for the JTAG controller and the Backup domain. The backup domain reset
resets the Backup domain. The resets can be triggered by an external signal, internal events
and the reset generators. More information about these resets will be described in the
following sections.
5.1.2.
Function overview
Power reset
The Power reset is generated by either an external reset as Power On and Power Down reset
(POR/PDR reset) or by the internal reset generator when exiting Standby mode. The power
reset sets all registers to their reset values except the Backup domain. The Power reset
whose active signal is low, it will be de-asserted when the internal LDO voltage regulator is
ready to provide 1.2V power. The RESET service routine vector is fixed at address 0x0000
0000 in the memory map.
System reset
A system reset is generated by the following events:
A power reset (POWER_RSTn).
An external pin reset (NRST).
A window watchdog timer reset (WWDGT_RSTn).
A free watchdog timer reset (FWDGT_RSTn).
The SYSRESETREQ bit in RISC-V Application Interrupt and Reset Control Register is
set (SW_RSTn).
Reset generated when entering Standby mode when resetting nRST_STDBY bit in User
Option Bytes (OB_STDBY_RSTn).
Reset generated when entering Deep-sleep mode when resetting nRST_DPSLP bit in
User Option Bytes (OB_DPSLP_RSTn).
A system reset resets the processor core and peripheral IP components except for the JTAG
controller and the Backup domain.
A system reset pulse generator guarantees low level pulse duration of 20 μs for each reset