Hi,
The firmware update procedure is straightforward. As far as I know, the board is nearly identical to the MaxESP Version 3, so we can use its instructions. I will outline my procedure below. I have only tested the mount control and guiding since I don't plan to use the focuser and rotator capabilities.
I
've placed all the necessary files in the following link:
drive.google.com/drive/folders/1-4CYK5T9...nSzOEJJKWHxmAypjo3_N
If something goes wrong, we can restore the original firmware using the ESP32 flash download tool, which is located in the same folder. I've tested this process many times without any issues but use it at your risk!
To update the firmware via the Arduino IDE, follow these steps:

1. Install Arduino IDE.
2. In the Arduino IDE, go to File > Preferences, and add the following URL to the "Additional Boards Manager URLs" box:
raw.githubusercontent.com/espressif/ardu...age_esp32_index.json
3. In the Arduino IDE, navigate to Tools > Board > Boards Manager and install the ESP32 support. I installed version 2.0.0.0.
4. Go to Sketch > Include Library > Add .ZIP Library, and browse to install 'DFRobot_SD3031-master.zip,' which is responsible for the RTC module.
5. Download and unzip 'OnStepX_1.zip.'
6. Open the Arduino IDE, go to File > Open, and select the 'OnStepX' folder. Then, open 'OnStepX.ino.'
7. In the 'Config.h' file, make the following modifications according to your preferences:

// I'm not sure if this is necessary
#define SERIAL_B_ESP_FLASHING ON

// Obtain these values from the Web Server before flashing:
#define AXIS1_STEPS_PER_DEGREE 3840
#define AXIS1_DRIVER_MICROSTEPS 16
#define AXIS2_STEPS_PER_DEGREE 3840
#define AXIS2_DRIVER_MICROSTEPS 16

#define GUIDE_TIME_LIMIT 40
#define TRACK_AUTOSTART ON
8. In the Tools menu, select the following options:

Boards: ESP32 Dev Module
CPU Frequency: 240MHz
Partition Scheme: Huge App
Port: Choose the device's USB serial port (the one that appears only when you plug in the USB cable going to the controller.)

9. Click the "Verify" button (the green checkmark icon).
10. If there are no errors, click "Upload."
11. When the "Connecting.............." message appears, hold the ESP32 button and briefly press the EN button. After the procedure completes, release the button and restart the device.
12. Connect to the board via INDI and verify communication.

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