ST STM32F105 series User Manual

Low-, medium-, high- and XL-density reset and clock control (RCC) RM0008
91/1128 DocID13902 Rev 15
Low-power management reset
There are two ways to generate a low-power management reset:
1. Reset generated when entering Standby mode:
This type of reset is enabled by resetting nRST_STDBY bit in User Option Bytes. In this
case, whenever a Standby mode entry sequence is successfully executed, the device
is reset instead of entering Standby mode.
2. Reset when entering Stop mode:
This type of reset is enabled by resetting nRST_STOP bit in User Option Bytes. In this
case, whenever a Stop mode entry sequence is successfully executed, the device is
reset instead of entering Stop mode.
For further information on the User Option Bytes, refer to the STM32F10xxx Flash
programming manual.
7.1.2 Power reset
A power reset is generated when one of the following events occurs:
1. Power-on/power-down reset (POR/PDR reset)
2. When exiting Standby mode
A power reset sets all registers to their reset values except the Backup domain (see
Figure 4)
These sources act on the NRST pin and it is always kept low during the delay phase. The
RESET service routine vector is fixed at address
0x0000_0004 in the memory map.
The system reset signal provided to the device is output on the NRST pin. The pulse
generator guarantees a minimum reset pulse duration of 20 µs for each reset source
(external or internal reset). In case of an external reset, the reset pulse is generated while
the NRST pin is asserted low.
Figure 7. Simplified diagram of the reset circuit
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ST STM32F105 series Specifications

General

Brand	ST
Model	STM32F105 series
Category	Microcontrollers
Language	English