When the port will not appear
No port in the Arduino IDE is one of three things: a cable with no data wires in it, a missing CH340 driver, or a USB-C to USB-C cable plugged in the one way up this board does not answer to. Check them in that order; each takes a minute.
What should appear
The ESP32 on this board has no USB of its own. A CH340 chip beside it turns USB into a serial port, and that serial port is what the Arduino IDE uploads through. When it is working, a new entry appears under Tools → Port the moment you plug the board in:
| Computer | The port looks like |
|---|---|
| Mac | /dev/cu.usbserial-… |
| Windows | COM3, COM4 and so on, listed as USB-SERIAL CH340 |
| Linux | /dev/ttyUSB0 |
Unplug the board and plug it back in while the menu is open. The entry that comes and goes is this board.
The cable
A charge-only cable has power wires and nothing else. The board runs from it, so it looks fine, and no port ever appears. It is the most common cause and the cheapest to rule out: use a cable you know moves data.
The driver
Recent versions of macOS and Windows usually have a CH340 driver already, and Linux has had one for years. If the board shows up as an unknown device, or not at all with a cable you trust, serial ports and drivers has the install for each system.
The way up
This one is particular to this board, and it only happens with a USB-C to USB-C cable. With a USB-A to USB-C cable the port always appears; with C-to-C it appears one way up and not the other.
The drawing is the usual cause of exactly that pattern, rather than something read off this board's schematic. The fix does not depend on which it is: turn the USB-C plug over, or use a USB-A to USB-C cable.
When it does not work
A board that is running proves the cable carries power, not data. Plenty of USB cables, especially the ones that came with a torch or a fan, have no data wires at all. Try a cable you have used to move files.
Usually a loose socket or an unpowered hub. Plug straight into the computer. If it drops the moment a sketch turns Wi-Fi on, the port is sagging under the transmit current: try another port or a powered hub.
The CH340 driver is missing. Windows usually fetches it by itself through Windows Update; if it has not, install it from the chip maker, WCH, and plug the board in again.
Then the cable, the driver and the orientation are all fine. The blink article covers the two upload failures that remain: the speed, and the missing BOOT button.
Two sockets for a cell, wired opposite ways round.
The battery sockets, and which pin is plus →Edit this page — content/books/esplipo/when-the-port-will-not-appear.mdx
Questions about this product
See what other owners have asked, and read their solutions.
ESP32 LiPo Dev Kit: 3 Boards with LiPo Charger + 3 Shields
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