hello_world

"Hello, world!" example

Building and running the example

1. Make sure you have a riscv-none-elf-gcc toolchain installed and added to PATH.
2. Build the example with CMake:

   cd examples/hello_world
   mkdir build
   cmake -B build -D target=esp32c3 -G Ninja .
   cmake --build build

   For other chip, please use the target=chip_name, where chip_name can be any from the supported ones. You should get the following output at the end:

   [2/3] Generating hello_world.bin
   copy from `hello_world' [elf32-littleriscv] to `hello_world.bin' [binary]
   [3/3] Running utility command for hello_world-size
   text	   data	    bss	    dec	    hex	filename
   5202	    132	    196	   5530	   159a	hello_world
   

   The following files will be generated:
   • hello_world — ELF output file
   • hello_world.bin — binary file for flashing into the chip
   • hello_world.map — linker map file
3. Flash the example using esptool:

   esptool.py --port /dev/ttyUSB0 --baud 921600 write_flash 0x0000 build/hello_world.bin

   (Adjust the serial port name as needed.)
4. See the serial output, for example using miniterm.py (assuming pyserial is installed):

   pyserial-miniterm /dev/ttyUSB0 115200

   You should see the following output:

   ESP-ROM:esp32c3-api1-20210207
   Build:Feb  7 2021
   rst:0x1 (POWERON),boot:0xc (SPI_FAST_FLASH_BOOT)
   Hello, world!
   

   The output will keep repeating with reset reasons such as TG0WDT_SYS_RST, RTCWDT_RTC_RST — this is because this example doesn't disable or feed the hardware watchdog timers.