Contents
What does NRST pin do?
In short, NRST pin is used to activate bootloader when you need to flash new program using one of the communication channels and to reset MCU to default state when you want to flash new program using SWD interface and SWD pins are not available.
What is nJTRST?
nJTRST = ‘not JTAG Reset’ The Naming can vary a little bit, so you can find in same Documents from STM JNTRST and nJTRST meaning the same Pin. Imen DAHMEN (ST Employee)
How does SWD work?
SWD is a modality that creates heat via emitted electromagnetic radio waves. The heat is produced by oscillation of high frequency electric and magnetic fields, most commonly at 27.2 MHz. Traditionally, there are two types of SWD units which create heat in different ways.
What is the use of NRST pin in STM32?
The content of flash is not changed, so previously written program is still available. Specifically, while NRST pin is connected to the ground the MCU stays in “reset state”, i.e. it does not do anything, the clocks are stopped and the program that is already flashed is not running.
Is there a reset signal on the NRST pin?
All internal reset sources provide a reset signal on the NRST pin, which can be used to reset other components of the application board. In addition, no external reset circuitry is needed due to the internal glitch filter and the safe power monitoring feature which guarantees the reset of the application when VDD is below the selected threshold.
In addition, no external reset circuitry is needed due to the internal glitch filter and the safe power monitoring feature which guarantees the reset of the application when VDD is below the selected threshold. An internal pull-up on the NRST pin, allows to maintain a high level when no reset signal is driven low.
Why is the STM32F7 RCC so important?
The STM32F7 RCC provides high flexibility in the choice of clock sources, which allows the system designer to meet both power consumption and accuracy requirements. The independent peripheral clocks allow a designer to adjust the system power consumption without impacting the communication baud rates.