Q: How do I use the onboard antenna or an external antenna?
As shown in the figure below, the antenna selection resistor is soldered to the left by default for the onboard antenna. Change it to be soldered to the right for an external antenna.
Q: What baud rates does CAN support?
This product uses the ESP32-S3 as the main control MCU, so the CAN communication baud rate can be freely configured in software
CAN (TWAI) interface: communication rate up to 1 Mbps
Q: What is the pitch of the onboard pin header?
Pin header pitch: 2.0 mm
Q: After downloading a program to the module, sometimes it fails to connect to the serial port or fails to flash during subsequent downloads?
Press and hold the BOOT button, press RESET at the same time, then release RESET, and then release the BOOT button. The module will then enter download mode. This resolves most download failures.
Q: The module keeps resetting, and when checking in Device Manager, the connection appears to be blinking?
This may be caused by a blank Flash, which makes the USB port unstable. Press and hold the BOOT button, press RESET at the same time, then release RESET, and then release the BOOT button. The module will then enter download mode. Flash the firmware (program) to resolve the issue.
Q: The first compilation is extremely slow. What should I do?
It is normal for the first compilation to be slow. Just wait patiently.
Q: How to handle the situation where the serial port shows 'waiting for download...' after a successful ESP-IDF flash?
If the board has a reset button, press it; if not, power cycle the board.
Q: How to handle the situation when the AppData folder cannot be found?
Some AppData folders are hidden by default and can be set to be visible
Path: Explorer->View->Check "Hidden items"
Q: How do I check which COM port I am using?
Windows system:
①Check via Device Manager: Press Windows + R to open the "Run" dialog box; type devmgmt.msc and press Enter to open Device Manager; expand the "Ports (COM & LPT)" section, which lists all COM ports and their current status
②Check via Command Prompt: Open Command Prompt (CMD); type the mode command, which displays status information for all COM ports
③Check the hardware connection: If you have connected an external device to a COM port, the device usually occupies a port number. You can determine which port is in use by checking the connected hardware
Linux system:
①Check via the dmesg command: Open a terminal
②Check via the ls command: Type ls /dev/ttyS* or ls /dev/ttyUSB* to list all serial devices
③Check via the setserial command: Type setserial -g /dev/ttyS* to view the configuration information for all serial devices
Q: Program fails to flash when using a MAC device?
Q: Why is there no output even though the code is correct and flashed successfully?
Check the schematic. For different development boards' Type-C interfaces, the corresponding code handles output differently:
For boards with direct USB output, the printf function is supported for printing. If you want to support the Serial function for printing, you need to enable the USB CDC On Boot feature or declare HWCDC.
For boards with UART-to-USB, both the printf function and the Serial function are supported for printing, and there is no need to enable USB CDC On Boot.
Q: When using CAN to control other devices, it is unresponsive or cannot communicate?
First check the serial parameters and cable connections. A CAN bus usually has termination enabled only at both ends of the main trunk line; if this product is at an endpoint of the bus, you can move the jumper cap to 120R so that the 120 Ω termination resistor is connected across L/H. Intermediate nodes should keep the termination resistor disabled
Q: Can I use the terminal block and the USB interface for power at the same time?
No, this may risk damaging the module.
Q: Please note!
The factory program is for learning purposes only. If you use it in a real application, please optimize the program logic yourself
