@owen 在 Where can I download a normal development environment? 中说： none_evm/ble_simple_peripheral I downloaded many different versions of gcc, but none of them could compile anything and wrote errors.. ble_simple_peripheral is not as simple as hello world Why can't you make the development environment all in one? You have to download everything from different places and even sdk from different places are different From everything that I read and looked at, I still did not understand how to set I / O ports and initiate the microcontroller (I did not find anything where it was written about this) so that it does not do anything, such as in avr: #define F_CPU 9600000UL #include <avr/io.h> int main(void) { // Set I/O DDRB |= 1<<PB4;//Pin 4 as output while(1){ } } This is one of the problems, and the main problem is that the examples for FR801x cannot be compiled