Environment setup

In my development I use currently MacOS. I have set up environment using  guide from Read the Docs. Jump to this page and check for update, I put quick list which is copy of their list

1. Instal pip package manager

   sudo easy_install pip

2. Install pyserial for accessing serial port

   sudo pip install pyserial

3. Download ESP32 toolchain from Espressif website and extract to esp directory
   

   cd
   curl -O https://dl.espressif.com/dl/xtensa-esp32-elf-osx-1.22.0-61-gab8375a-5.2.0.tar.gz
   mkdir -p ~/esp
   cd ~/esp
   tar -xzf ~/xtensa-esp32-elf-osx-1.22.0-61-gab8375a-5.2.0.tar.gz

4. Update your PATH variable either by creating alias or setting updating .profile file

   export PATH=$PATH:$HOME/esp/xtensa-esp32-elf/bin

5. Get ESP32 API and libraries from Espressif’s ESP-IDF repository.

   cd ~/esp
   git clone --recursive https://github.com/espressif/esp-idf.git

6. Set IDF_PATH variable so toolchain has access to ESP-IDF

   export IDF_PATH=~/esp/esp-idf

7. Check device name of serial connection to ESP32. As I am using Mac I run the command below twice – with unplugged and plugged board to identify correct device

   

   ls /dev/tty.*
   /dev/tty.usbserial-DN01DXXH

   Note name of the port as it will be needed later.

8. When plugged check if chip is working using for example screen command

   screen /dev/tty.usbserial-DN01DXXH 115200

   Output should be similiar to
   

   Example output of serial from ESP32

Getting Hello World

ESP-IDF comes with several example projects, here we start traditionally with Hello World. Let’s copy it to esp directory to test it.

cd ~/esp
cp -r $IDF_PATH/examples/get-started/hello_world .

Jump to the directory and using make command execute configuration utility menuconfig.

cd ~/esp/hello_world
make menuconfig

Set serial port to correct one for your machine.

Now just build, flash and see if it works

make flash
Flashing binaries to serial port /dev/tty.usbserial-DN01DXXH (app at offset 0x10000)...
esptool.py v2.0-beta3
Connecting......
Uploading stub...
Running stub...
Stub running...
Configuring flash size...
Auto-detected Flash size: 4MB
Flash params set to 0x0220
Compressed 15824 bytes to 9221...
Wrote 15824 bytes (9221 compressed) at 0x00001000 in 0.8 seconds (effective 152.2 kbit/s)...
Hash of data verified.
Compressed 355088 bytes to 167202...
Wrote 355088 bytes (167202 compressed) at 0x00010000 in 14.9 seconds (effective 191.1 kbit/s)...
Hash of data verified.
Compressed 3072 bytes to 82...
Wrote 3072 bytes (82 compressed) at 0x00008000 in 0.0 seconds (effective 1548.1 kbit/s)...
Hash of data verified.
Leaving...
Hard resetting...

and if everything went fine

make monitor

I (1143) cpu_start: Starting scheduler on PRO CPU.
Hello world!
I (202) cpu_start: Starting scheduler on APP CPU.
This is ESP32 chip with 2 CPU cores, WiFi/BT/BLE, silicon revision 0, 4MB external flash
Restarting in 10 seconds...
Restarting in 9 seconds...
Restarting in 8 seconds...
Restarting in 7 seconds...
Restarting in 6 seconds...
Restarting in 5 seconds...
Restarting in 4 seconds...
Restarting in 3 seconds...
Restarting in 2 seconds...

What next

Definitely important reading is project and components structure. I will try and address it during next exercises.

Furthermore some more reading on memory and partitions and application entry points.

void app_main()
{
    printf("Hello world!\n");
    /* Print chip information */
    esp_chip_info_t chip_info;
    esp_chip_info(&chip_info);

It is app_main.

Coming back to reading, flashing and hopefully I’ll manage to explain it more and better.

/Rook